WO2025210020A1

WO2025210020A1 - Uplink transmission configuration for sbfd

Info

Publication number: WO2025210020A1
Application number: PCT/EP2025/058830
Authority: WO
Inventors: Shin Horng Wong; Naoki Kusashima
Original assignee: Sony Europe Ltd; Sony Group Corp
Current assignee: Sony Europe BV United Kingdom Branch; Sony Group Corp
Priority date: 2024-04-04
Filing date: 2025-04-01
Publication date: 2025-10-09
Anticipated expiration: 2026-10-04

Abstract

A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network is provided. The method comprises determining that the communications device has an uplink signal to transmit to the wireless communications network, determining, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and transmitting the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode.

Description

UPLINK TRANSMISSION CONFIGURATION FOR SBFD

BACKGROUND

Field of Disclosure

The present disclosure relates to communications devices, infrastructure equipment, and methods for the more efficient and effective transmission of data in a wireless communications network.

The present application claims the Paris Convention priority from European patent application number EP24168596.5, filed on 4 April 2024, the contents of which are hereby incorporated by reference.

Description of Related Art

The “background” description provided herein is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description which may not otherwise qualify as prior art at the time of filing, are neither expressly or impliedly admitted as prior art against the present invention.

Previous generation mobile telecommunication systems, such as those based on the 3GPP defined UMTS and Long Term Evolution (LTE) architecture, are able to support a wider range of services than simple voice and messaging services offered by previous generations of mobile telecommunication systems. For example, with the improved radio interface and enhanced data rates provided by LTE systems, a user is able to enjoy high data rate applications such as mobile video streaming and mobile video conferencing that would previously only have been available via a fixed line data connection. The demand to deploy such networks is therefore strong and the coverage area of these networks, i.e. geographic locations where access to the networks is possible, is expected to continue to increase rapidly.

Current and future wireless communications networks are expected to routinely and efficiently support communications with an ever-increasing range of devices associated with a wider range of data traffic profiles and types than existing systems are optimised to support. For example, it is expected future wireless communications networks will be expected to efficiently support communications with devices including reduced complexity devices, machine type communication (MTC) devices, high resolution video displays, virtual reality headsets, extended Reality (XR) and so on. Some of these different types of devices may be deployed in very large numbers, for example low complexity devices for supporting the “The Internet of Things”, and may typically be associated with the transmissions of relatively small amounts of data with relatively high latency tolerance. Other types of device, for example supporting high-definition video streaming, may be associated with transmissions of relatively large amounts of data with relatively low latency tolerance. Other types of device, for example used for autonomous vehicle communications and for other critical applications, may be characterised by data that should be transmitted through the network with low latency and high reliability. A single device type might also be associated with different traffic profiles / characteristics depending on the application(s) it is running. For example, different considerations may apply for efficiently supporting data exchange with a smartphone when it is running a video streaming application (high downlink data) as compared to when it is running an Internet browsing application (sporadic uplink and downlink data) or being used for voice communications by an emergency responder in an emergency scenario (data subject to stringent reliability and latency requirements).

In view of this there is expected to be a desire for current wireless communications networks, for example those which may be referred to as 5G or new radio (NR) systems / new radio access technology (RAT) systems, or indeed future 6G wireless communications, as well as future iterations / releases of existing systems, to efficiently support connectivity for a wide range of devices associated with different applications and different characteristic data traffic profiles and requirements.

SUMMARY OF THE DISCLOSURE

The present disclosure can help address or mitigate at least some of the issues discussed above.

Embodiments of the present technique can provide a method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network. The method comprises determining that the communications device has an uplink signal to transmit to the wireless communications network, determining, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and transmitting the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode.

Such embodiments of the present technique, which, in addition to methods of operating communications devices, relate to methods of operating infrastructure equipment, to communications devices and infrastructure equipment, to circuitry for communications devices and infrastructure equipment, to wireless communications systems, to computer programs, and to computer-readable storage mediums, can allow for the more efficient and effective transmission of uplink signals by a communications device.

Respective aspects and features of the present disclosure are defined in the appended claims.

It is to be understood that both the foregoing general description and the following detailed description are exemplary, but are not restrictive, of the present technology. The described embodiments, together with further advantages, will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

A more complete appreciation of the disclosure and many of the attendant advantages thereof will be readily obtained as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein like reference numerals designate identical or corresponding parts throughout the several views, and wherein:

Figure 1 schematically represents some aspects of an LTE-type wireless telecommunication system which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 2 schematically represents some aspects of a new radio access technology (RAT) wireless telecommunications system which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 3 is a schematic block diagram of an example infrastructure equipment and communications device which may be configured to operate in accordance with certain embodiments of the present disclosure;

Figure 4 schematically represents a first example of non-overlapping sub-bands for uplink and downlink transmissions;

Figure 5 schematically represents second and third examples of non-overlapping sub-bands for uplink and downlink transmissions;

Figure 6 schematically illustrates an example of intra-cell cross link interference;

Figure 7 illustrates an example of transmission power leakage; Figure 8 illustrates an example of receiver power selectivity;

Figure 9 illustrates an example of inter sub-band interference;

Figure 10 shows an example illustrating how a user equipment (UE) may apply precoding to multiple antenna ports when performing uplink transmissions;

Figure 11 shows an example illustrating how a gNB may use separate antenna panels for sub-band full duplex (SBFD) and non-SBFD transmission/reception;

Figure 12 shows a part schematic, part message flow diagram representation of an example wireless communications system comprising a communications device and an infrastructure equipment in accordance with embodiments of the present technique; and

Figure 13 shows a flow diagram illustrating an example process of communications in a communications system in accordance with embodiments of the present technique.

DETAILED DESCRIPTION OF THE EMBODIMENTS

Long Term Evolution Advanced Radio Access Technology (4G)

Figure 1 provides a schematic diagram illustrating some basic functionality of a mobile telecommunications network / system 6 operating generally in accordance with LTE principles, but which may also support other radio access technologies, and which may be adapted to implement embodiments of the disclosure as described herein. Various elements of Figure 1 and certain aspects of their respective modes of operation are well-known and defined in the relevant standards administered by the 3GPP (RTM) body, and also described in many books on the subject, for example, Holma H. and Toskala A [1], It will be appreciated that operational aspects of the telecommunications networks discussed herein which are not specifically described (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be implemented in accordance with any known techniques, for example according to the relevant standards and known proposed modifications and additions to the relevant standards.

The network 6 includes a plurality of base stations 1 connected to a core network 2. Each base station provides a coverage area 3 (i.e. a cell) within which data can be communicated to and from communications devices 4. Although each base station 1 is shown in Figure 1 as a single entity, the skilled person will appreciate that some of the functions of the base station may be carried out by disparate, inter-connected elements, such as antennas (or antennae), remote radio heads, amplifiers, etc. Collectively, one or more base stations may form a radio access network.

Data is transmitted from base stations 1 to communications devices 4 within their respective coverage areas 3 via a radio downlink (DL). Data is transmitted from communications devices 4 to the base stations 1 via a radio uplink (UL). The core network 2 routes data to and from the communications devices 4 via the respective base stations 1 and provides functions such as authentication, mobility management, charging and so on. Communications devices may also be referred to as mobile stations, user equipment (UEs), user terminals, mobile radios, mobile terminals, terminal devices, wireless transmit and receive units (WTRUs), and so forth. Services provided by the core network 2 may include connectivity to the internet or to external telephony services. The core network 2 may further track the location of the communications devices 4 so that it can efficiently contact (i.e. page) the communications devices 4 for transmitting downlink data towards the communications devices 4.

Base stations, which are an example of network infrastructure equipment, may also be referred to as transceiver stations, nodeBs, e-nodeBs, eNB, g-nodeBs, gNB and so forth. In this regard different terminology is often associated with different generations of wireless telecommunications systems for elements providing broadly comparable functionality. However, certain embodiments of the disclosure may be equally implemented in different generations of wireless telecommunications systems, and for simplicity certain terminology may be used regardless of the underlying network architecture. That is to say, the use of a specific term in relation to certain example implementations is not intended to indicate these implementations are limited to a certain generation of network that may be most associated with that particular terminology.

New Radio Access Technology (5G)

Systems incorporating NR technology are expected to support different services (or types of services), which may be characterised by different requirements for latency, data rate and/or reliability. For example, Enhanced Mobile Broadband (eMBB) services are characterised by high capacity with a requirement to support up to 20 Gb/s. The requirements for Ultra Reliable and Low Latency Communications (URLLC) services are for one transmission of a 32 byte packet to be transmitted from the radio protocol layer 2/3 SDU ingress point to the radio protocol layer 2/3 SDU egress point of the radio interface within 1 ms with a reliability of 1 - 10'⁵ (99.999 %) or higher (99.9999%) [2],

Massive Machine Type Communications (mMTC) is another example of a service which may be supported by NR-based communications networks. In addition, systems may be expected to support further enhancements related to Industrial Internet of Things (IIoT) in order to support services with new requirements of high availability, high reliability, low latency, and in some cases, high-accuracy positioning.

An example configuration of a wireless communications network which uses some of the terminology proposed for and used in NR and 5G is shown in Figure 2. In Figure 2 a plurality of transmission and reception points (TRPs) 10 are connected to distributed control units (DUs) 41, 42 by a connection interface represented as a line 16. Each of the TRPs 10 is arranged to transmit and receive signals via a wireless access interface within a radio frequency bandwidth available to the wireless communications network. Thus, within a range for performing radio communications via the wireless access interface, each of the TRPs 10, forms a cell of the wireless communications network as represented by a circle 12. As such, wireless communications devices 14 which are within a radio communications range provided by the cells 12 can transmit and receive signals to and from the TRPs 10 via the wireless access interface. Each of the distributed units 41, 42 are connected to a central unit (CU) 40 (which may be referred to as a controlling node) via an interface 46. The central unit 40 is then connected to the core network 20 which may contain all other functions required to transmit data for communicating to and from the wireless communications devices and the core network 20 may be connected to other networks 25.

The elements of the wireless access network shown in Figure 2 may operate in a similar way to corresponding elements of an LTE network as described with regard to the example of Figure 1. It will be appreciated that operational aspects of the telecommunications network represented in Figure 2, and of other networks discussed herein in accordance with embodiments of the disclosure, which are not specifically described (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be implemented in accordance with any known techniques, for example according to currently used approaches for implementing such operational aspects of wireless telecommunications systems, e.g. in accordance with the relevant standards.

The TRPs 10 of Figure 2 may in part have a corresponding functionality to a base station or eNodeB of an LTE network. Similarly, the communications devices 14 may have a functionality corresponding to the UE devices 4 known for operation with an LTE network. It will be appreciated therefore that operational aspects of a new RAT network (for example in relation to specific communication protocols and physical channels for communicating between different elements) may be different to those known from LTE or other known mobile telecommunications standards. However, it will also be appreciated that each of the core network component, base stations and communications devices of a new RAT network will be functionally similar to, respectively, the core network component, base stations and communications devices of an LTE wireless communications network.

In terms of broad top-level functionality, the core network 20 connected to the new RAT telecommunications system represented in Figure 2 may be broadly considered to correspond with the core network 2 represented in Figure 1, and the respective central units 40 and their associated distributed units / TRPs 10 may be broadly considered to provide functionality corresponding to the base stations 1 of Figure 1. The term network infrastructure equipment / access node may be used to encompass these elements and more conventional base station type elements of wireless telecommunications systems. Depending on the application at hand the responsibility for scheduling transmissions which are scheduled on the radio interface between the respective distributed units and the communications devices may lie with the controlling node / central unit and / or the distributed units / TRPs. A communications device 14 is represented in Figure 2 within the coverage area of the first communication cell 12. This communications device 14 may thus exchange signalling with the first central unit 40 in the first communication cell 12 via one of the distributed units / TRPs 10 associated with the first communication cell 12.

It will further be appreciated that Figure 2 represents merely one example of a proposed architecture for a new RAT based telecommunications system in which approaches in accordance with the principles described herein may be adopted, and the functionality disclosed herein may also be applied in respect of wireless telecommunications systems having different architectures.

Thus, certain embodiments of the disclosure as discussed herein may be implemented in wireless telecommunication systems / networks according to various different architectures, such as the example architectures shown in Figures 1 and 2. It will thus be appreciated the specific wireless telecommunications architecture in any given implementation is not of primary significance to the principles described herein. In this regard, certain embodiments of the disclosure may be described generally in the context of communications between network infrastructure equipment / access nodes and a communications device, wherein the specific nature of the network infrastructure equipment / access node and the communications device will depend on the network infrastructure for the implementation at hand. For example, in some scenarios the network infrastructure equipment / access node may comprise a base station, such as an LTE-type base station 1 as shown in Figure 1 which is adapted to provide functionality in accordance with the principles described herein, and in other examples the network infrastructure equipment may comprise a control unit / controlling node 40 and / or a TRP 10 of the kind shown in Figure 2 which is adapted to provide functionality in accordance with the principles described herein.

A more detailed diagram of some of the components of the network shown in Figure 2 is provided by Figure 3. In Figure 3, a TRP 10 as shown in Figure 2 comprises, as a simplified representation, a wireless transmitter 30, a wireless receiver 32 and a controller or controlling processor 34 which may operate to control the transmitter 30 and the wireless receiver 32 to transmit and receive radio signals to one or more UEs 14 within a cell 12 formed by the TRP 10. As shown in Figure 3, an example UE 14 is shown to include a corresponding transmitter 49, a receiver 48 and a controller 44 which is configured to control the transmitter 49 and the receiver 48 to transmit signals representing uplink data to the wireless communications network via the wireless access interface formed by the TRP 10 and to receive downlink data as signals transmitted by the transmitter 30 and received by the receiver 48 in accordance with the conventional operation. The transmiters 30, 49 and the receivers 32, 48 (as well as other transmiters, receivers and transceivers described in relation to examples and embodiments of the present disclosure) may include radio frequency fdters and amplifiers as well as signal processing components and devices in order to transmit and receive radio signals in accordance for example with the 5G/NR standard. The controllers 34, 44 (as well as other controllers described in relation to examples and embodiments of the present disclosure) may be, for example, a microprocessor, a CPU, or a dedicated chipset, etc., configured to carry out instructions which are stored on a computer readable medium, such as a non-volatile memory. The processing steps described herein may be carried out by, for example, a microprocessor in conjunction with a random access memory, operating according to instructions stored on a computer readable medium. The transmiters, the receivers and the controllers are schematically shown in Figure 3 as separate elements for ease of representation. However, it will be appreciated that the functionality of these elements can be provided in various different ways, for example using one or more suitably programmed programmable computer(s), or one or more suitably configured application-specific integrated circuit(s) / circuitry / chip(s) / chipset(s). As will be appreciated the infrastructure equipment / TRP / base station as well as the UE / communications device will in general comprise various other elements associated with its operating functionality.

As shown in Figure 3, the TRP 10 also includes a network interface 50 which connects to the DU 42 via a physical interface 16. The network interface 50 therefore provides a communication link for data and signalling traffic from the TRP 10 via the DU 42 and the CU 40 to the core network 20.

The interface 46 between the DU 42 and the CU 40 is known as the F 1 interface which can be a physical or a logical interface. The Fl interface 46 between CU and DU may operate in accordance with specifications 3GPP TS 38.470 and 3GPP TS 38.473, and may be formed from a fibre optic or other wired or wireless high bandwidth connection. In one example the connection 16 from the TRP 10 to the DU 42 is via fibre optic. The connection between a TRP 10 and the core network 20 can be generally referred to as a backhaul, which comprises the interface 16 from the network interface 50 of the TRP 10 to the DU 42 and the Fl interface 46 from the DU 42 to the CU 40.

In order for a UE such as UE 4 or 14 to transmit uplink data to the network (e.g. on a Physical Uplink Control Channel (PUCCH) or a Physical Uplink Shared Channel (PUSCH)) to, for example, base station 1 or TRP 10, the UE must first ensure it is synchronised with the network on the uplink. Since a particular eNB or gNB expects to be receiving communications from many UEs, it needs to ensure that it shares a common timing understanding with each of these UEs (i.e. they are synchronised in terms of the starting times of frames and Orthogonal Frequency Division Multiplexing (OFDM) symbols). This is so that the eNB is able to schedule communication with each of them in a manner that avoids collisions and to ensure orthogonality of the uplink signals, such that inter-subcarrier interference is avoided or mitigated.

Although reference is made to 5G networks, the discussions in this specification apply equally to 6G networks (and beyond) where there is expected to be significantly higher throughput, lower latency and higher reliability utilising sub-THz frequencies.

Full Duplex Time Division Duplex (FD-TDD)

NR/5G networks can operate using Time Division Duplex (TDD), where an entire frequency band or carrier is switched to either downlink or uplink transmissions for a time period and can be switched to the other of downlink or uplink transmissions at a later time period. Currently, TDD operates in Half Duplex mode (HD-TDD) where the gNB or UE can, at a given time, either transmit or receive packets, but not both at the same time. As wireless networks transition from NR to 5G- Advanced networks, a proposed new feature of such networks is to enhance duplexing operation for Time Division Duplex (TDD) by enabling Full Duplex operation in TDD (FD-TDD) [3], [4],

In FD-TDD, a gNB can transmit and receive data to and from the UEs at the same time on the same frequency band. In addition, a UE can operate either in HD-TDD or FD-TDD mode, depending on its capability. For example, when UEs are only capable of supporting HD-TDD, FD-TDD is achieved at the gNB by scheduling a DL transmission to a first UE and scheduling a UL transmission from a second UE within the same orthogonal frequency division multiplexing (OFDM) symbol (i.e. at the same time). Conversely, when UEs are capable of supporting FD-TDD, FD-TDD is achieved both at the gNB and the UE, where the gNB can simultaneously schedule this UE with DL and UL transmissions within the same OFDM symbol by scheduling the DL and UL transmissions at different frequencies (e.g. physical resource blocks (PRBs)) of the system bandwidth. A UE supporting FD-TDD requires more complex hardware than a UE that only supports HD-TDD. Development of current 5G networks is focused primarily on enabling FD-TDD at the gNB with UEs operating in HD-TDD mode.

Motivations for enhancing duplexing operation for TDD include an improvement in system capacity, reduced latency, and improved uplink coverage. For example, in current HD-TDD systems, OFDM symbols are allocated only for either a DL or UL direction in a semi-static manner. Hence, if one direction experiences less or no data, the spare resources cannot be used in the other direction, or are, at best, under-utilised. However, if resources can be used for DL data and UL data (as in FD-TDD) at the same time, the resource utilisation in the system can be improved. Furthermore, in current HD-TDD systems, a UE can receive DL data, but cannot transmit UL data at the same time, which causes delays. If a gNB or UE is allowed to transmit and receive data at the same time (as with FD-TDD), the traffic latency will be improved. In addition, UEs are usually coverage limited in their UL transmissions when located close to the edge of a cell. While the UE coverage at the cell-edge can be improved if more time domain resources are assigned to UL transmissions (e.g. repetitions), for HD-TDD systems, if the UL direction is assigned more time resources, fewer time resources can be assigned to the DL direction, which can lead to system imbalance. In contrast, in FD-TDD, continuous UL resources can be assigned for repetition opportunities whilst allowing DL traffic to occur in those resources, thereby UL enhancing coverage without causing system imbalance.

Sub-band Full Duplex (SBFD)

In Sub-band Full Duplex (SBFD), the frequency resource of a TDD system bandwidth or Bandwidth Part (BWP) (i.e. at the UE/gNB) is divided into two or more non-overlapping sub-bands, where each sub-band can be DL or UL [5], Guard sub-bands may be used between DL and UL sub-bands to reduce inter subband interference. In the current 5G system, only one UL sub-band can be configured in an OFDM symbol.

An example is shown in Figure 4, where simultaneous DL and UL transmissions occur in three different non-overlapping sub-bands 401 to 403, i.e. in different sets of frequency Resource Blocks (RB): Subband#! 401, Sub-band#2 402, Sub-band#3 403. The example of Figure 4 is referred to as {DUD}, because two sub-bands, Sub-band# 1 401 and Sub-band#3 403, are used for DL transmissions whilst one sub-band, Sub-band#2 402, is used for UL transmissions. To reduce leakage from one sub-band 401 to 403 to another, a guard sub-band 410 may be configured between UL and DL sub-bands 401 to 403. Guard sub-bands 410 are configured between DL Sub-band#3 403 and UL Sub-band#2 402 and between UL Sub-band#2 402 and DL Sub-band# 1 401.

Figure 5 shows two further examples with a DL and UL sub-band separated by a guard sub-band, where here, the UL sub-band can be configured to occupy the lower frequency portion of the BWP whilst the DL sub-band occupies higher frequency portion of the BWP {UD} or the UL sub-band occupies the higher frequency portion of the BWP whilst the DL sub-band occupies lower frequency portion of the BWP {DU}. Here, on the left-side of Figure 5, a UL sub-band# 1 501 is separated from a DL sub-band#2 503 by a guard sub-band 502 - this sub-band arrangement is referred to as {UD}. In this case, the DL sub-band#2 503 occupies a higher frequency portion of the system bandwidth than the UL sub-band# 1 501. On the right-side of Figure 5, a DL sub-band# 1 504 is separated from a UL sub-band#2 506 by a guard sub-band 505 - this sub-band arrangement is referred to as {DU}. In this case, the UL sub-band#2 506 occupies a higher frequency portion of the system bandwidth than the DL sub-band# 1 504.

While Figures 4 and 5 show the system bandwidth as being divided into either two or three sub-bands, those skilled in the art would appreciate that the concept of SBFD may (in further releases of the 3GPP specifications, for example) be extended such that any number of sub-bands could be used, if deemed beneficial. For example, the system bandwidth may be divided into four sub-bands, which may, using the example of Figure 4, include the two downlink sub-bands 401, 403, the uplink sub-band 402 and another uplink sub-band, though other sub-band arrangements are envisioned. Guard sub-bands may be used in substantially any sub-band arrangement.

Intra-Cell Cross Link Interference (CLI)

FD-TDD employing SBFD suffers from intra-cell cross link interference (CLI) at the gNB and at the UE. An example is shown in Figure 6, where a gNB 610 is capable of FD-TDD and is simultaneously receiving UL transmission 631 from UE1 621 and transmitting a DL transmission 642 to UE2 622. At the gNB 610, intra-cell CLI is caused by the DL transmission 642 at the gNB’s transmitter self-interfering 641 with its own receiver that is trying to decode UL signals 631. At UE2 622, intra-cell CLI 632 is caused by an aggressor UE, e.g. UE1 621, transmitting in the UL 631, whilst a victim UE, e.g. UE2 622, is receiving a DL signal 642.

The intra-cell CLI at the gNB due to self-interference can be significant, as the DL transmission can in some cases be over 100 dB more powerful than the UL reception. Accordingly, complex RF hardware and interference cancellation are required to isolate this self-interference. As noted above, guard bands may be inserted between two sub-bands of different link directions as shown in Figures 4 and 5 and described above. Furthermore, separate antenna panels may be used for transmissions and receptions at the gNB to provide spatial isolation between the DL and UL thereby reducing gNB self-interference.

Inter Sub-Band Interference

The use of SBFD is considered as a way of reducing self-interference at the gNB. However, SBFD may suffer from inter (and indeed intra) sub-band interferences, which are caused by transmission leakage and receiver’s selectivity. Although a transmission is typically scheduled within a specific frequency channel (or sub-band), i.e. a specific set of RBs, transmission power can leak out to other channels. This occurs because channel filters are not perfect, and as such the roll-off of the filter will cause power to leak into channels adjacent to the intended specific frequency channel. While the following discussion uses the term channel, the discussion equally applies to sub-bands, such as the sub-bands shown in Figures 4 and 5.

An example of transmission generating adjacent channel leakage is shown in Figure 7. Here, the wanted transmission (Tx) power is the transmission power in the selected frequency band (i.e. the assigned channel 710). Due to roll-off of the transmission filter and nonlinearities in components of the transmitter, some transmission power is leaked into adjacent channels (including an adjacent channel 720), as shown in Figure 7. The ratio of the power within the assigned frequency channel 710 to the power in the adjacent channel 720 is the Adjacent Channel Leakage Ratio (ACLR). The leakage power 750 will cause interference at a receiver that is receiving the signal in the adjacent channels 720.

Similarly, a receiver’s fdter is also not perfect and will receive unwanted power from adjacent channels due to its own filter roll-off. An example of filter roll-off at a receiver is shown in Figure 8. Here, a receiver is configured to receive transmissions in an assigned channel 810. However, the imperfect nature of the receiver filter means that some transmission power 850 can be received in adjacent channels 820. Therefore, if a signal 830 is transmitted on an adjacent channel 820, the receiver will inadvertently receive the adjacent signal 830 in the adjacent channel 820, to an extent. The ratio of the received power in the assigned frequency channel 810 to the received power 850 in the adjacent channel 820 is the Adjacent Channel Selectivity (ACS).

The combination of the ACL from the transmitter and the ACS of a receiver will lead to adjacent channel interference (ACI), otherwise known as inter-sub-band interference, at the receiver. An example is shown in Figure 9, where an aggressor transmits a signal 910 in an adjacent channel at a lower frequency than the victim’s receiving 920 channel. The interference 950 caused by the aggressor’s transmission includes the ACL 951 of the aggressor’s transmitting filter and the ACS 952 of the victim’s receiving filter. In other words, the receiver will experience interference 950 in the ACI frequency range shown in Figure 9.

As such, due to adjacent channel interference (ACI), cross link interference (CLI) will still occur despite the use of different sub-bands 401 to 403 for DL and UL transmissions in a FD-TDD cell as shown in the example of Figure 4, or sub bands 501 and 503, and 504 and 506 in the examples of Figure 5.

UL Transmission Modes

Precoding may be applied to UL transmissions from a UE to the gNB to improve the UL signal quality or for multiple-input-multiple-output (MIMO) transmissions. The precoding weights are applied to the UE antenna ports. There are up to eight UE antenna ports in the current 5G system. The antenna ports are not physical antennas of the UE, but are inputs to a spatial filter that connects with the actual physical UE antennas. An example is shown in Figure 10, where the UE has two antenna ports 1001 and 1002. The precoding weights W\ and R2, which are obtained 1003 by the UE either from a precoding codebook or via a determination made by the UE, are applied 1004a and 1004b to the signal going into antenna ports 1001 and 1002 respectively. The signal from each port 1001, 1002 goes through a spatial filter 1005 which may consist of additional complex weights applied to the signal prior to it being transmitted via the one or more physical antennas 1006a to 1006d (of which there are four in the example of Figure 10). It should be noted that the number of antenna ports can be different to the number of physical antennas, and one port can be connected to all physical antennas or to a subset of them.

There are two main UL transmission modes which determine the precoding weights used by the UE. These are Codebook Based and Non-Codebook Based UL transmission. In existing implementations, the UE is semi-statically configured to use either Codebook Based or Non-Codebook Based UL transmission. The configuration to use either Codebook based or Non-Codebook based transmission is indicated by the RRC parameter txConfig in ISiSCH-co fig. which is a UE-specific parameter applicable to a particular BWP. If the txConfig parameter is absent, the UE transmits a PUSCH (or other uplink signal) by using one antenna port only.

In Codebook Based UL transmission mode, the UE is configured with one or more codebooks, and the gNB indicates the precoding from one of those codebooks that the UE is to use in the Transmit Precoding Matrix Index (TPMI) field in the UL Grant scheduling the PUSCH (or other uplink signal). The gNB determines the UL precoder with the help of Sounding Reference Signal (SRS) that are transmitted by the UE to the gNB in the uplink.

In Non-Codebook Based UL transmission mode, the UE determines the precoding weight by itself, without any TPMI indication from the gNB. In TDD operations, the UE may use channel reciprocity to determine the precoding weights for its UL transmission. For example, the UE may measure the Channel State Information Reference Signal (CSI-RS) or Synchronisation Signal Block (SSB) in the DL, and assume channel reciprocity (i.e. that the characteristics of the channel in the uplink are similar to or the same as those measured via CSI-RS or SSB in the downlink) to determine a set of suitable precoding weights for the UL.

In TDD, the DL and UL may share the same antenna panel, but this would cause significant high inter sub-band CLI, or self-interference, at the gNB when the gNB performs simultaneous DL transmission and UL reception in SBFD OFDM symbols using this shared antenna panel. One way to reduce selfinterference at the gNB receiver is to use separate antenna panels for DL and UL for SBFD OFDM symbols rather than a shared antenna panel.

An example is shown in Figure 11, showing a {DXXXU} slot format, where D = DL slot, X = SBFD slot and U = UL slot. The gNB uses three antenna panels, a “TDD” panel 1101 used for DL transmission and UL reception in DL and UL OFDM symbols respectively, a “DL” panel 1102 used for DL transmission in DL sub-bands of SBFD OFDM symbols, and a “UL” panel 1103 used for UL reception in UL sub-bands of SBFD OFDM symbols. By using physically separated DL and UL antenna panels 1102, 1103 during simultaneous transmission/reception in SBFD sub-bands, spatial isolation is introduced between the DL transmission and the UL reception at the gNB, thereby reducing gNB self-interference. Here, in the example of Figure 11, PDSCH#1 is in a DL slot and the gNB uses the “TDD” antenna panel 1101 to transmit PDSCH#1, and similarly, the gNB uses the “TDD” antenna panel 1101 to receive PUSCH#2 from the UE, which is transmitted within an UL slot by the UE. PDSCH#2 and PUSCH#1 are transmissions to/from different UEs and they are scheduled at the same time in the DL sub-band and UL sub-band of a single SBFD slot in Slot w+2 respectively. Here, PDSCH#2 is therefore transmitted using the “DL” antenna panel 1102 whist PUSCH#1 is received using the “UL” antenna panel 1103 to reduce self-interference .

One advantage of TDD over FDD is the gNB and UE can use channel reciprocity in determining their transmissions. Channel reciprocity assumes that within a channel coherent time, the DL radio channel and UL radio channel are similar in the same frequency resource, and since TDD uses the same frequency resources for DL and UL, the UE/gNB can utilise channel reciprocity. In addition to using the same frequency resources for DL and UL, channel reciprocity is made feasible by using same antenna panel at the gNB for DL and UL, so that DL and UL transmissions go through the same radio propagation path, for example in Figure 11, the “TDD” antenna panel 1101 is used for DL and UL, thereby enabling channel reciprocity.

Since DL transmission and UL reception at the gNB may use different antenna panels for SBFD OFDM symbols, the assumption that there is channel reciprocity between DL and UL may no longer be valid, as these different antenna panels are not physically at the same location meaning that the radio propagation paths with respect to each panel are different. Non-Codebook Based UL transmissions can therefore no longer utilise channel reciprocity. Hence, a technical problem to solve is how to manage UL transmission precoding for SBFD and non-SBFD UL transmissions. Embodiments of the present technique seek to provide solutions to such a technical problem. Dynamic UL Transmission Mode in SBFD Operation

Figure 12 shows a part schematic, part message flow diagram representation of a wireless communications system comprising a communications device 1210 (e.g. a UE 14) and an infrastructure equipment 1220 (e.g. a gNB / TRP 10) in accordance with at least some embodiments of the present technique. The communications device 1210 may be configured to transmit signals to and/or receive signals from the wireless communications network, for example, to and from the infrastructure equipment 1220. Specifically, the communications device 1210 may be configured to transmit data to and/or receive data from the wireless communications network (e.g. to/from the infrastructure equipment 1220) via a wireless radio interface provided by the wireless communications network (e.g. a Uu interface between the communications device 1210 and the Radio Access Network (RAN), which includes the infrastructure equipment 1220). The communications device 1210 and the infrastructure equipment 1220 each comprise a transceiver (or transceiver circuitry) 1211, 1221, and a controller (or controller circuitry) 1212, 1222. Each of the controllers 1212, 1222 may be, for example, a microprocessor, a CPU, or a dedicated chipset, etc. The controllers 1212, 1222 may also each be equipped with a memory unit (which is not shown in Figure 12).

As shown in the example of Figure 12, the controller 1212 of the communications device 1210 is configured to control the transceiver 1211 of the communications device 1210 to determine 1230 that the communications device 1210 has an uplink signal to transmit to the wireless communications network (e.g. to the infrastructure equipment 1220), to determine 1240, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network (e.g. from the infrastructure equipment 1220), whether the communications device 1210 is to transmit the uplink signal to the wireless communications network (e.g. to the infrastructure equipment 1220) in accordance with a first uplink transmission mode or a second uplink transmission mode, and to transmit 1250 the uplink signal to the wireless communications network (e.g. to the infrastructure equipment 1220) in accordance with the determined 1240 one of the first uplink transmission mode and the second uplink transmission mode.

Essentially then, embodiments of the present technique, as exemplified by the example wireless communications system of Figure 12 for example, propose that the UL transmission mode is dynamically switched. Embodiments of the present technique recognise that the radio propagation channel may change between SBFD and non-SBFD OFDM symbols, and also between DL and UL sub-bands of the same SBFD OFDM symbols due to changes in antenna panels. This is in contrast to legacy systems where, for TDD operation, the antenna panel is the same for DL and UL reception as described above with reference to the example of Figure 11, and hence the UL transmission mode can be configured in a semi-static manner since the DL and UL radio channel relation is unlikely to change in a dynamic manner.

In some arrangements of embodiments of the present technique, the dynamic switching of UL transmission mode is to switch between UL transmission based on gNB indicated precoder (i.e. TPMI) and/or UL beam (i.e. SRS resource indicator or SRS resource set indication), and UL transmission not based on gNB indicated precoder and UL beam (i.e., the UE determines the precoder and UL beam). In other words, the first uplink transmission mode may comprise performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network (e.g. gNB), and the second uplink transmission mode may comprise performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device, wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam. In at least some implementations of such arrangements, the said switching of UL transmission mode is to switch between codebook based UL transmission mode and non-codebook based UL transmission mode. In the case where UL transmission based on gNB indicated precoder and/or UL beam is indicated, the gNB also indicates the precoder and/or UL beam to the UE for its UL transmission. In other words, the first parameters may be indicated in a codebook received from the wireless communications network (e.g. gNB), the codebook indicating multiple sets of parameters including the first parameters, and the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

In some arrangements of embodiments of the present technique, the UE determines which UL transmission mode to use based on the type of OFDM symbol the UL transmission uses. That is, the UE determines by itself without dynamic signalling which UL transmission mode to use. In other words, the communications device may be configured to determine whether the communications device is to transmit the uplink signal to the wireless communications network (e.g. the gNB) in accordance with the first uplink transmission mode or the second uplink transmission mode based on either a parameter of the uplink signal, where the parameter of the uplink signal may be a type of one or more symbols in which the communications device is to transmit the uplink signal, wherein the type of the one or more symbols is either sub-band full duplex (SBFD) or non-SBFD.

In at least some implementations of such arrangements, the codebook based UL transmission mode is used for UL transmission in SBFD OFDM symbols whilst the non-codebook based UL transmission mode is used for UL transmission in UL OFDM symbols. In other words, when the one or more symbols are SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network (e.g. gNB), while when the one or more symbols are non-SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device. Such implementations recognise that channel reciprocity is available for an UL transmission in UL OFDM symbols since the gNB receives the UL transmission from the UE using the “TDD” antenna panel, and thereby non-codebook based UL transmission is feasible. However, channel reciprocity may not be available for an UL transmission in an UL sub-band of SBFD OFDM symbols since gNB receives the UL transmission using an “UL” antenna panel that is different for DL transmission, and thereby codebook based UL transmission is more suitable.

In some arrangements of embodiments of the present technique, an UL transmission in SBFD OFDM symbols always applies codebook based transmission whilst an UL transmission in UL OFDM symbols applies the UL transmission mode configured by the txConfig. In other words, when the one or more symbols are SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network (e.g. gNB), while when the one or more symbols are non-SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via radio resource control (RRC) signalling received from the wireless communications network (e.g. gNB), wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device.

In some arrangements of embodiments of the present technique, UL transmission in SBFD OFDM symbols applies the UL transmission mode configured by a first RRC parameter whilst UL transmission in UL OFDM symbols applies the UL transmission mode configured by a second RRC parameter. This means that a different (i.e. new) txConfig is configured in addition to the legacy txConfig in RRC when SBFD operation is configured. In other words, when the one or more symbols are SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via first RRC signalling received from the wireless communications network (e.g. gNB), and when the one or more symbols are non-SBFD symbols, the communications device may be configured to determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via second RRC signalling received from the wireless communications network (e.g. gNB).

In some arrangements of embodiments of the present technique, the network may indicate dynamically what UL transmission mode or modes are to be used by a UE when performing an UL transmission depending on the type of (e.g. SBFD or non-SFBD) OFDM symbols used for that UL transmission. In some implementations of such arrangements, the gNB may independently configure dynamically which UL transmission mode is used for both (or all) types of OFDM symbols. In other words, the dynamic downlink indication may indicate that the uplink signal is to be transmitted in accordance with the first uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and the uplink signal is to be transmitted in accordance with the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, where here, the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

In other implementations of such arrangements, the gNB may configure which UL transmission mode is used for one (or some) type of OFDM symbols; for example, the gNB may dynamically configure the UL transmission mode for non-SFBD symbols, but the UE will always use a pre-configured UL transmission mode (e.g. codebook based UL transmission) for SFBD symbols as described in the arrangements above. In other words, the dynamic downlink indication may indicate that the uplink signal is to be transmitted in accordance with either the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and wherein the uplink signal is to be transmitted by the communications device in accordance with a preconfigured one of the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, where here, the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

In some other arrangements of embodiments of the present technique, the network may indicate semi- statically (e.g. via RRC signalling) what UL transmission mode or modes are to be used by a UE when performing an UL transmission depending on the type of (e.g. SBFD or non-SFBD) OFDM symbols used forthat UL transmission. In some implementations of such arrangements, the gNB may configure which UL transmission mode is used for one (or some) type of OFDM symbols; for example, the gNB may configure, semi-statically, the UL transmission mode for non-SFBD symbols, but the UE will always use a pre-configured UL transmission mode (e.g. codebook based UL transmission) for SFBD symbols as described in the arrangements above. In other words, the infrastructure equipment (e.g. gNB) may be configured to transmit, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment (e.g. gNB) in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD

In some other implementations of such arrangements, the gNB may independently configure, semi- statically, which UL transmission mode is used for both (or all) types of OFDM symbols. In other words, the infrastructure equipment (e.g. gNB) may further be configured to transmit, to the communications device, a second indication via radio resource control, RRC, signalling, the second indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a second type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the second type is the other of SBFD or non-SBFD.

In some arrangements of embodiments of the present technique, the network dynamically indicates the UL transmission mode to the UE. In other words, the communications device may be configured to determine whether the communications device is to transmit the uplink signal to the wireless communications network (e.g. the gNB) in accordance with the first uplink transmission mode or the second uplink transmission mode based on a dynamic downlink indication received from the wireless communications network (e.g. gNB). For example, the network can indicate whether a PUSCH or PUCCH uses codebook based UL transmission mode or non-codebook based UL transmission mode. Such arrangements recognise that the gNB may use the “TDD” antenna panel for DL transmission and UL reception in different SBFD OFDM symbols, i.e., non-simultaneous DL transmission and UL reception, thereby not causing self-interference, and so it may indicate the UE to use non-codebook based UL transmission in such a case. Similarly, the gNB may use the “DL” antenna panel for DL transmission and “UL” antenna panel for UL reception for non-SBFD OFDM symbols, in which case, the UE may be indicated to use codebook based UL transmission.

In some arrangements of embodiments of the present technique, the said dynamic indicator is indicated in the DCI, such as the UL grant. In other words, the dynamic downlink indication may be received from the wireless communications network (e.g. gNB) within downlink control information (DCI) where the DCI may be an uplink grant which schedules the transmission of the uplink signal. That is, the gNB indicates in the UL grant the UL transmission mode the UE should use on the scheduled PUSCH.

In some arrangements of embodiments of the present technique, the said dynamic indicator is indicated in the DL grant. In other words, the DCI may be a downlink grant which schedules the transmission of the uplink signal in response to the communications device receiving downlink data from the wireless communications network (e.g. gNB). That is, the gNB indicates in the DL grant the UL transmission mode the UE should use on the scheduled PUCCH.

In some arrangements of embodiments of the present technique, the said dynamic indicator is indicated in the GC-DCI. In other words, the DCI may be a group common DCI (GC-DCI) wherein the GC-DCI is also transmitted by the wireless communications network (e.g. gNB) to one or more other communications devices. This is, the gNB indicates in the GC-DCI, such as in a Slot Format Indicator (SFI) for example, the UL transmission mode the UE should use on corresponding timing (symbols, slots, etc.). In some arrangements of embodiments of the present technique, the said dynamic indicator is indicated in the RAR. The RAR is used to schedule PUSCH carrying Message 3 of a random access (RACH) process. In current systems, the UE uses the same UL beam for Message 3 and PRACH preambles. Since the UL radio channel may be different for UL transmissions in SBLD and non-SBLD OLDM symbols, it may not be suitable to use the same UL beam for a PRACH preamble transmitted in SBLD OLDM symbol and a Message 3 PUSCH in UL OLDM symbol, and vice-versa. Here, the RAR indicates whether the UE can assume the same UL beam for the PRACH preamble and Message 3, or not. If the RAR indicates that the UE cannot assume the same UL beam used for PRACH preamble for Message 3, then the RAR also indicates the UL beam and may additionally the precoder for Message 3 UL transmission. In other words, the dynamic downlink indication may be received from the wireless communications network (e.g. gNB) within a random access response (RAR) message, wherein the RAR is received in response to the communications device transmitting a random access (RACH) preamble to the wireless communications network (e.g. gNB) to initiate a RACH procedure.

In some arrangements of embodiments of the present technique, if the dynamic switching mentioned in any of the above described arrangements of embodiments of the present technique is not supported/configured for a UE with SBLD operation, codebook based transmission or single antenna transmission is supported for any UL transmission. That means therefore that non-codebook based transmission is not allowed to be used for the UE in such a case. In other words, the infrastructure equipment (e.g. gNB) may be configured to determine, if the communications device is not able to dynamically determine whether to transmit the uplink signal in accordance with the codebook based uplink transmission mode or the non-codebook based uplink transmission mode and if the uplink signal is to be transmitted by the communications device within one or more sub-band full duplex, SBLD, symbols, that the infrastructure equipment is to receive the uplink signal from the communications device in accordance with the codebook based uplink transmission mode.

In some arrangements of embodiments of the present technique, the network signals one or more channel adjustment factor between the DL and UL antenna panels. Additionally or alternatively, the gNB signals one or more channel adjustment factors between the “DL” or “UL” antenna panel and the “TDD” antenna panel, where the channel adjustment factor equalizes the radio channel between the DL and UL among the antenna panels. In other words, the communications device may be configured to receive, from the wireless communications network (e.g. gNB), an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network (e.g. gNB) and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on the received channel adjustment factor. This enables the UE to determine the precoding for UL transmission by applying the channel adjustment factor on the channel sounding made in the DL. The UE can therefore perform non-codebook based transmission mode on UL transmissions using channel reciprocity with an additional application of this channel adjustment factor.

In some implementations of such arrangements, the gNB may determine the channel adjustment factor by calculating the difference between the UE reported downlink measurements from RS (such as CSI-RS or SSB) transmitted using the “DL” antenna panel with the SRS received in from the UE in the “UL” antenna panel. The channel adjustment factor between the “DL” or “UL” antenna panel and the “TDD” panel can be determined using the same method. In other words, the infrastructure equipment (e.g. gNB) may be configured to determine the channel adjustment factor based on a difference between a first signal quality of first reference signals and a second signal quality of second reference signals, wherein the infrastructure equipment (e.g. gNB) had transmitted the first reference signals via the first antenna panel to the communications device and received an indication of the first signal quality from the communications device, and wherein the infrastructure equipment (e.g. gNB) had received the second reference signals from the communications device via the second antenna panel and performed measurements on the second reference signals to determine the second signal quality.

In some other implementations of such arrangements, the channel adjustment factor can be determined a- priori by the network operator, by determining the difference in physical distance in number of wavelengths between the “DL” and “UL” antenna panels, and between the “DL” and “TDD” antenna panels. In other words, the channel adjustment factor may be preconfigured and known to the infrastructure equipment (e.g. gNB).

In some arrangements of embodiments of the present technique, the channel adjustment factor is signalled to the UE dynamically using a DCI. In other words, the indication of the channel adjustment factor may be received by the communications device from the wireless communications network (e.g. gNB) within a DCI.

In some arrangements of embodiments of the present technique, the channel adjustment factor is semi- statically signalled to the UE using RRC signalling. In other words, the indication of the channel adjustment factor may be received by the communications device from the wireless communications network (e.g. gNB) within RRC signalling.

In some arrangements of embodiments of the present technique, the gNB indicates which DL RS, such as CSI-RS and SSB, the UE cannot assume channel reciprocity. In other words, the communications device may be configured to receive, from the wireless communications network (e.g. gNB), an indication of a set one or more downlink reference signals, DL RS, for which the communications device is not to assume channel reciprocity. For example, the radio channel condition derived from DL RS that is transmitted using the “DL” antenna panel may not be the same for the UL, especially if the UL is received in another antenna panel at the gNB. Hence, the UE cannot use such DL RS to determine its precoding and/or UL beam for its UL transmission. Accordingly, the UE uses other DL RS to those indicated by the gNB to determine which precoding and UL beam should be applied for its UL transmission. In other words, if the communications device determines that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode, the second uplink transmission mode may comprise performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on one or more DL RS which are not part of the indicated set of DL RS.

In some arrangements of embodiments of the present technique, the UE assumes that it may not determine its precoding weight and/or UL beam from either DL RS transmitted in the DL sub-band of SBFD OFDM symbols since they do not have the same radio channel condition or from DL RS transmitted in non-SFBD OFDM symbols via the gNB’s TDD antenna panel if the UL transmission is to be transmitted in the UL sub-band of SFBD symbols (as this will be received via the gNB’s UL antenna panel). In other words, if the communications device determines that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode, the second uplink transmission mode may comprise performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device without assuming channel reciprocity between the transmission of the uplink signal and reception of one or more DL RS from the wireless communications network. In some arrangements of embodiments of the present technique, the gNB indicates the corresponding channel adjustment factor for each DL RS, where channel reciprocity cannot be assumed. In other words, the communications device may be configured to receive, from the wireless communications network (e.g. gNB) for each of the indicated set of DL RS, an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network (e.g. gNB) and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on a DL RS of the indicated set of DL RS in combination with the received channel adjustment factor for that DL RS. Here, the gNB indicates the channel adjustment factor between DL RS from “DL” antenna panel and “UL” antenna panel. Additionally or alternatively, the gNB also indicates the channel adjustment factor between DL RS from “TDD” antennal panel an “UL” antenna panel. The UE can then determine which channel adjustment factor to use depending which DL RS it uses to determine the precoding/UL beam for its UL transmission.

DCI carries fields with different bit sizes for codebook based UL transmission when compared to noncodebook UL transmission. For example, a field used to indicate TPMI requires many bits for codebook based transmission, while such a field is not needed for non-codebook based transmission. If the total bit size in the DCI is different to what the UE expects, the UE cannot correctly decode the DCI. Even if the total bit size in the DCI is the same as the UE expects it to be, but the fields used to indicate TPMI in the DCI are different, the UE misunderstands the contents of the DCI because of a wrong interpretation of the bit fields.

In some arrangements of embodiments of the present technique therefore, the UE attempts to blindly decode for the DCI assuming two different DCI bit sizes on all search spaces. In other words, receiving the DCI may comprise the communications device being configured to blindly decode for a DCI of a first size and for a DCI of a second size, wherein the dynamic downlink indication received within a DCI of the first size may indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, and wherein the dynamic downlink indication received within a DCI of the second size may indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode.

In some arrangements of embodiments of the present technique, a new DCI format is carried in addition to the legacy DCI format. The legacy DCI format may indicate either the codebook or non-codebook UL transmission mode, while the new DCI format may indicate the other. In other words, if the DCI has a first format, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, and if the DCI has a second format, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode. By identifying different DCI formats, the network can control the UE in respect of DCI blind decoding. For example, one search space may be allocated to the legacy DCI format only and another search space may be allocated to the new DCI format only.

In some arrangements of embodiments of the present technique, a new indicator is used in the DCI, where the indicator may in some implementations be a 1 -bit indicator, which indicates either that the codebook or the non-codebook UL transmission mode is to be used by the UE for its UL transmission. In other words, the DCI comprises an indicator, and wherein, if the indicator indicates the first UL transmission mode, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, and if the indicator indicates the second UL transmission mode, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode.

In some arrangements of embodiments of the present technique, the indication of either the codebook or the non-codebook UL transmission mode is carried by a Radio Network Temporary Identifier (RNTI). In other words, if an identifier of the DCI is equal to a first identifier, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode, and if the identifier of the DCI is equal to a second identifier, the communications device may determine that it is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode. For example, a Cell-RNTI (C-RNTI) may be associated with codebook based transmission while another C- RNTI may be associated with non-codebook based transmission. If the RNTI of a DCI is different to either of these C-RNTIs, the UE will fail to decode the DCI, since the UE expects the RNTI of the DCI to be equal to one of these C-RNTIs. By knowing a DQ’s structure based on its RNTI, the UE does not need to assume multiple interpretations for the DCI.

In some arrangements of embodiments of the present technique, one of the TPMI indices is used to indicate the non-codebook based UL transmission mode, whilst the remaining TPMI indices are used to indicate the precoder as per legacy operation. In other words, the DCI may comprise an indication of a transmit precoding matrix index, TPMI, field capable of indicating a set of TPMI values, wherein a first TPMI value may indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode by performing precoding of the uplink signal in accordance with second precoding weights independently determined by the communications device, and wherein one or more other TPMI values to the first TPMI value may each indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode by performing precoding of the uplink signal in accordance with first precoding weights associated with that TPMI value. As described above, TPMI points to an index in a lookup table consisting of precoding weights for each UE antenna port. Here, one of the TPMI field indices is repurposed and used to indicate the noncodebook based UL transmission mode.

In some arrangements of embodiments of the present technique, one of the SRS Resource Indicator (SRI) values may be used to indicate the non-codebook UL transmission mode. In other words, the DCI comprises an indication of a sounding reference signal resource indicator, SRI, field capable of indicating a set of SRI values, wherein a first SRI value may indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the second uplink transmission mode by performing transmission of the uplink signal using a second uplink beam independently determined by the communications device, and wherein one or more other SRI values to the first SRI value may each indicate that the communications device is to transmit the uplink signal to the wireless communications network (e.g. gNB) in accordance with the first uplink transmission mode by performing transmission of the uplink signal using a first uplink beam associated with that SRI value. The UE can be configured with multiple SRS, where practically (but not necessarily), each SRS is transmitted to the gNB by using a different UL beam. The gNB uses the SRI field in the UL grant to indicate which UL beam to use. Hence, one of the SRI indicators is used to indicate non-codebook UL transmission mode whilst the remaining SRI indicators are used to indicate UL beams for codebook based UL transmission mode. Figure 13 shows a flow diagram illustrating an example process of communications in a communications system in accordance with embodiments of the present technique. The process shown by Figure 13 is specifically a method of operating a communications device (e.g. UE) configured to transmit signals to and/or to receive signals from an infrastructure equipment (e.g. a gNB) of a wireless communications network.

The method begins in step SI. The method comprises, in step S2, determining that the communications device has an uplink signal to transmit to the wireless communications network (e.g. to the infrastructure equipment). In step S3, the process comprises determining, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network (e.g. from the infrastructure equipment), whether the communications device is to transmit the uplink signal to the wireless communications network (e.g. to the infrastructure equipment) in accordance with a first uplink transmission mode or a second uplink transmission mode. The method then comprises, in step S4, transmitting the uplink signal to the wireless communications network (e.g. to the infrastructure equipment) in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode. The process ends in step S5.

Those skilled in the art would appreciate that the method shown by Figure 13 may be adapted in accordance with embodiments of the present technique. For example, other intermediate steps may be included in such a method, or the steps may be performed in any logical order. Though embodiments of the present technique have been described largely by way of the example communications system shown in Figure 12, it would be clear to those skilled in the art that they could be equally applied to other systems to those described herein, provided that these are within the scope of the claims.

Those skilled in the art would further appreciate that such infrastructure equipment and/or communications devices as herein defined may be further defined in accordance with the various arrangements and embodiments discussed in the preceding paragraphs. It would be further appreciated by those skilled in the art that such infrastructure equipment and communications devices as herein defined and described may form part of communications systems other than those defined by the present disclosure, provided that these are within the scope of the claims.

The following numbered paragraphs provide further example aspects and features of the present technique:

Paragraph 1. A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network, the method comprising determining that the communications device has an uplink signal to transmit to the wireless communications network, determining, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and transmitting the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode. Paragraph 2. A method according to Paragraph 1, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

Paragraph 3. A method according to Paragraph 2, wherein the first parameters are indicated in a codebook received from the wireless communications network, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

Paragraph 4. A method according to any of Paragraphs 1 to 3, wherein the parameter of the uplink signal is a type of one or more symbols in which the communications device is to transmit the uplink signal, wherein the type of the one or more symbols is either sub-band full duplex, SBFD, or non-SBFD. Paragraph 5. A method according to Paragraph 4, wherein when the one or more symbols are SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network.

Paragraph 6. A method according to Paragraph 5, wherein when the one or more symbols are non- SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device.

Paragraph 7. A method according to Paragraph 5 or Paragraph 6, wherein when the one or more symbols are non-SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via radio resource control, RRC, signalling received from the wireless communications network, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device.

Paragraph 8. A method according to any of Paragraphs 4 to 7, wherein when the one or more symbols are SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via first RRC signalling received from the wireless communications network, and when the one or more symbols are non-SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via second RRC signalling received from the wireless communications network.

Paragraph 9. A method according to any of Paragraphs 1 to 8, wherein the dynamic downlink indication is received from the wireless communications network within downlink control information, DCI.

Paragraph 10. A method according to Paragraph 9, wherein the DCI is an uplink grant which schedules the transmission of the uplink signal.

Paragraph 11. A method according to Paragraph 9 or Paragraph 10, wherein the DCI is a downlink grant which schedules the transmission of the uplink signal in response to the communications device receiving downlink data from the wireless communications network.

Paragraph 12. A method according to any of Paragraphs 9 to 11, wherein the DCI is a group common DCI, GC-DCI, wherein the GC-DCI is also transmitted by the wireless communications network to one or more other communications devices.

Paragraph 13. A method according to any of Paragraphs 9 to 12, wherein receiving the DCI comprises the communications device blindly decoding for a DCI of a first size and for a DCI of a second size, wherein the dynamic downlink indication received within a DCI of the first size indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and wherein the dynamic downlink indication received within a DCI of the second size indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

Paragraph 14. A method according to any of Paragraphs 9 to 13, wherein if the DCI has a first format, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the DCI has a second format, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

Paragraph 15. A method according to any of Paragraphs 9 to 14, wherein the DCI comprises an indicator, and wherein if the indicator indicates the first uplink transmission mode, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the indicator indicates the second uplink transmission mode, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

Paragraph 16. A method according to any of Paragraphs 9 to 15, wherein if an identifier of the DCI is equal to a first identifier, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the identifier of the DCI is equal to a second identifier, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

Paragraph 17. A method according to any of Paragraphs 9 to 16, wherein the DCI comprises an indication of a transmit precoding matrix index, TPMI, field capable of indicating a set of TPMI values, wherein a first TPMI value indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode by performing precoding of the uplink signal in accordance with second precoding weights independently determined by the communications device, and wherein one or more other TPMI values to the first TPMI value each indicate that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode by performing precoding of the uplink signal in accordance with first precoding weights associated with that TPMI value.

Paragraph 18. A method according to any of Paragraphs 9 to 17, wherein the DCI comprises an indication of a sounding reference signal resource indicator, SRI, field capable of indicating a set of SRI values, wherein a first SRI value indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode by performing transmission of the uplink signal using a second uplink beam independently determined by the communications device, and wherein one or more other SRI values to the first SRI value each indicate that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode by performing transmission of the uplink signal using a first uplink beam associated with that SRI value.

Paragraph 19. A method according to any of Paragraphs 1 to 18, wherein the dynamic downlink indication is received from the wireless communications network within a random access response, RAR, message, wherein the RAR is received in response to the communications device transmitting a random access, RACH, preamble to the wireless communications network to initiate a RACH procedure.

Paragraph 20. A method according to any of Paragraphs 1 to 19, comprising receiving, from the wireless communications network, an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on the received channel adjustment factor.

Paragraph 21. A method according to Paragraph 20, wherein the indication of the channel adjustment factor is received from the wireless communications network within a DCI.

Paragraph 22. A method according to Paragraph 20 or Paragraph 21, wherein the indication of the channel adjustment factor is received from the wireless communications network within RRC signalling. Paragraph 23. A method according to any of Paragraphs 1 to 22, comprising receiving, from the wireless communications network, an indication of a set one or more downlink reference signals, DL RS, for which the communications device is not to assume channel reciprocity.

Paragraph 24. A method according to Paragraph 23, wherein if the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on one or more DL RS which are not part of the indicated set of DL RS. Paragraph 25. A method according to Paragraph 23 or Paragraph 24, comprising receiving, from the wireless communications network for each of the indicated set of DL RS, an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on a DL RS of the indicated set of DL RS in combination with the received channel adjustment factor for that DL RS.

Paragraph 26. A method according to any of Paragraphs 1 to 25, wherein if the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device without assuming channel reciprocity between the transmission of the uplink signal and reception of one or more DL RS from the wireless communications network.

Paragraph 27. A communications device comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to determine that the communications device has an uplink signal to transmit to the wireless communications network, to determine, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to transmit the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode. Paragraph 28. Circuitry for a communications device, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to determine that the communications device has an uplink signal to transmit to the wireless communications network, to determine, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to transmit the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode. Paragraph 29. A method of operating an infrastructure equipment forming part of a wireless communications network, the method comprising determining that infrastructure equipment is to receive an uplink signal from a communications device, transmitting, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and receiving the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

Paragraph 30. A method according to Paragraph 29, wherein the first uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with first parameters indicated by the infrastructure equipment, wherein the second uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

Paragraph 31. A method according to Paragraph 30, wherein the first parameters are indicated in a codebook transmitted by the infrastructure equipment to the communications device, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

Paragraph 32. A method according to Paragraph 31, comprising determining, if the communications device is not able to dynamically determine whether to transmit the uplink signal in accordance with the codebook based uplink transmission mode or the noncodebook based uplink transmission mode and if the uplink signal is to be transmitted by the communications device within one or more sub-band full duplex, SBFD, symbols, that the infrastructure equipment is to receive the uplink signal from the communications device in accordance with the codebook based uplink transmission mode. Paragraph 33. A method according to any of Paragraphs 29 to 32, wherein the dynamic downlink indication indicates that the uplink signal is to be transmitted in accordance with either the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and wherein the infrastructure equipment determines that the uplink signal is to be transmitted in accordance with a preconfigured one of the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, and wherein the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

Paragraph 34. A method according to any of Paragraphs 29 to 33, wherein the dynamic downlink indication indicates that the uplink signal is to be transmitted in accordance with the first uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and the uplink signal is to be transmitted in accordance with the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, wherein the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

Paragraph 35. A method according to any of Paragraphs 29 to 34, wherein the dynamic downlink indication is transmitted to the communications device within downlink control information, DCI. Paragraph 36. A method according to Paragraph 35, wherein the DCI is an uplink grant which schedules the transmission of the uplink signal.

Paragraph 37. A method according to Paragraph 35 or Paragraph 36, wherein the DCI is a downlink grant which schedules the transmission of the uplink signal in response to the infrastructure equipment transmitting downlink data to the communications device.

Paragraph 38. A method according to any of Paragraphs 35 to 37, wherein the DCI is a group common DCI, GC-DCI, wherein the GC-DCI is also transmitted by the infrastructure equipment to one or more other communications devices.

Paragraph 39. A method according to any of Paragraphs 35 to 38, wherein if the DCI has a first size, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the DCI has a second size, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

Paragraph 40. A method according to any of Paragraphs 35 to 39, wherein if the DCI has a first format, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the DCI has a second format, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

Paragraph 41. A method according to any of Paragraphs 35 to 40, wherein the DCI comprises an indicator, and wherein if the indicator indicates the first uplink transmission mode, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the indicator indicates the second uplink transmission mode, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

Paragraph 42. A method according to any of Paragraphs 35 to 41, wherein if an identifier of the DCI is equal to a first identifier, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the identifier of the DCI is equal to a second identifier, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

Paragraph 43. A method according to any of Paragraphs 35 to 42, wherein the DCI comprises an indication of a transmit precoding matrix index, TPMI, field capable of indicating a set of TPMI values, wherein a first TPMI value indicates that the uplink signal is to be transmitted in accordance with the second uplink transmission mode by the communications device performing precoding of the uplink signal in accordance with second precoding weights independently determined by the communications device, and wherein one or more other TPMI values to the first TPMI value each indicate that the uplink signal is to be transmitted in accordance with the first uplink transmission mode by the communications device performing precoding of the uplink signal in accordance with first precoding weights associated with that TPMI value.

Paragraph 44. A method according to any of Paragraphs 35 to 43, wherein the DCI comprises an indication of a sounding reference signal resource indicator, SRI, field capable of indicating a set of SRI values, wherein a first SRI value indicates that the uplink signal is to be transmitted in accordance with the second uplink transmission mode by the communications device performing transmission of the uplink signal using a second uplink beam independently determined by the communications device, and wherein one or more other SRI values to the first SRI value each indicate that the uplink signal is to be transmitted in accordance with the first uplink transmission mode by the communications device performing transmission of the uplink signal using a first uplink beam associated with that SRI value. Paragraph 45. A method according to any of Paragraphs 29 to 44, wherein the dynamic downlink indication is transmitted to the communications device within a random access response, RAR, message, wherein the RAR is received in response to the infrastructure equipment receiving a random access, RACH, preamble from the communications device to initiate a RACH procedure.

Paragraph 46. A method according to any of Paragraphs 29 to 45, comprising transmitting, to the communications device, an indication of a channel adjustment factor between a first antenna panel of the infrastructure equipment and a second antenna panel of the infrastructure equipment, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on the indicated channel adjustment factor.

Paragraph 47. A method according to Paragraph 46, comprising determining the channel adjustment factor based on a difference between a first signal quality of first reference signals and a second signal quality of second reference signals, wherein the infrastructure equipment had transmitted the first reference signals via the first antenna panel to the communications device and received an indication of the first signal quality from the communications device, and wherein the infrastructure equipment had received the second reference signals from the communications device via the second antenna panel and performed measurements on the second reference signals to determine the second signal quality.

Paragraph 48. A method according to Paragraph 46 or Paragraph 47, wherein the channel adjustment factor is preconfigured and known to the infrastructure equipment.

Paragraph 49. A method according to any of Paragraphs 46 to 48, wherein the indication of the channel adjustment factor is transmitted to the communications device within a DCI.

Paragraph 50. A method according to any of Paragraphs 46 to 49, wherein the indication of the channel adjustment factor is transmitted to the communications device within RRC signalling.

Paragraph 51. A method according to any of Paragraphs 29 to 50, comprising transmitting, to the communications device, an indication of a set one or more downlink reference signals, DL RS, for which the communications device is not to assume channel reciprocity.

Paragraph 52. A method according to Paragraph 51, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on one or more DL RS which are not part of the indicated set of DL RS.

Paragraph 53. A method according to Paragraph 51 or Paragraph 52, comprising transmitting, to the communications device for each of the indicated set of DL RS, an indication of a channel adjustment factor between a first antenna panel of the infrastructure equipment and a second antenna panel of the infrastructure equipment, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on a DL RS of the indicated set of DL RS in combination with the indicated channel adjustment factor for that DL RS. Paragraph 54. An infrastructure equipment forming part of a wireless communications network, the infrastructure equipment comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to determine that infrastructure equipment is to receive an uplink signal from a communications device, to transmit, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to receive the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

Paragraph 55. Circuitry for an infrastructure equipment forming part of a wireless communications network, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to determine that infrastructure equipment is to receive an uplink signal from a communications device, to transmit, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to receive the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

Paragraph 56. A method of operating an infrastructure equipment forming part of a wireless communications network, the method comprising transmitting, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

Paragraph 57. A method according to Paragraph 56, wherein transmitting, to the communications device, a second indication via radio resource control, RRC, signalling, the second indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a second type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the second type is the other of SBFD or non-SBFD.

Paragraph 58. A method according to Paragraph 56 or Paragraph 57, wherein the first uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with first parameters indicated by the infrastructure equipment, wherein the second uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

Paragraph 59. A method according to Paragraph 58, wherein the first parameters are indicated in a codebook transmitted by the infrastructure equipment to the communications device, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

Paragraph 60. An infrastructure equipment forming part of a wireless communications network, the infrastructure equipment comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to transmit, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

Paragraph 61. Circuitry for an infrastructure equipment forming part of a wireless communications network, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to transmit, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

Paragraph 62. A wireless communications system comprising a communications device according to Paragraph 27 and an infrastructure equipment according to Paragraph 54 or Paragraph 60.

Paragraph 63. A computer program comprising instructions which, when loaded onto a computer, cause the computer to perform a method according to any of Paragraphs 1 to 26, Paragraphs 29 to 53, or Paragraphs 56 to 59.

Paragraph 64. A non-transitory computer-readable storage medium storing a computer program according to Paragraph 63.

It will be appreciated that the above description for clarity has described embodiments with reference to different functional units, circuitry and/or processors. However, it will be apparent that any suitable distribution of functionality between different functional units, circuitry and/or processors may be used without detracting from the embodiments.

Described embodiments may be implemented in any suitable form including hardware, software, firmware or any combination of these. Described embodiments may optionally be implemented at least partly as computer software running on one or more data processors and/or digital signal processors. The elements and components of any embodiment may be physically, functionally and logically implemented in any suitable way. Indeed, the functionality may be implemented in a single unit, in a plurality of units or as part of other functional units. As such, the disclosed embodiments may be implemented in a single unit or may be physically and functionally distributed between different units, circuitry and/or processors.

Although the present disclosure has been described in connection with some embodiments, it is not intended to be limited to the specific form set forth herein. Additionally, although a feature may appear to be described in connection with particular embodiments, one skilled in the art would recognise that various features of the described embodiments may be combined in any manner suitable to implement the technique.

References

[1] Holma H. and Toskala A, “LTE for UMTS OFDMA and SC-FDMA based radio access”, John Wiley and Sons, 2009.

[2] TR 38.913, “3^rd Generation Partnership Project; Technical Specification Group Radio Access Network; Study on Scenarios and Requirements for Next Generation Access Technologies

(Release 14)”, 3GPP, vl4.3.0, August 2017.

[3] RP -213591, “New SI: Study on evolution of NR duplex operation,” CMCC, RAN#94e, December 2021.

[4] RP -220633, “Revised SID: Study on evolution of NR duplex operation,” CMCC, RAN#95e, March 2022.

[5] European Patent No. 3545716.

Claims

CLAIMS What is claimed is:

1. A method of operating a communications device configured to transmit signals to and/or to receive signals from a wireless communications network, the method comprising determining that the communications device has an uplink signal to transmit to the wireless communications network, determining, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and transmitting the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode.

2. A method according to Claim 1, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

3. A method according to Claim 2, wherein the first parameters are indicated in a codebook received from the wireless communications network, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

4. A method according to Claim 1, wherein the parameter of the uplink signal is a type of one or more symbols in which the communications device is to transmit the uplink signal, wherein the type of the one or more symbols is either sub-band full duplex, SBFD, or non-SBFD.

5. A method according to Claim 4, wherein when the one or more symbols are SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, wherein the first uplink transmission mode comprises performing transmission of the uplink signal in accordance with first parameters indicated by the wireless communications network.

6. A method according to Claim 5, wherein when the one or more symbols are non-SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device.

7. A method according to Claim 5, wherein when the one or more symbols are non-SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via radio resource control, RRC, signalling received from the wireless communications network, wherein the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device.

8. A method according to Claim 4, wherein when the one or more symbols are SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via first RRC signalling received from the wireless communications network, and when the one or more symbols are non-SBFD symbols, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with one of the first uplink transmission mode and the second uplink transmission indicated via second RRC signalling received from the wireless communications network.

9. A method according to Claim 1, wherein the dynamic downlink indication is received from the wireless communications network within downlink control information, DCI.

10. A method according to Claim 9, wherein the DCI is an uplink grant which schedules the transmission of the uplink signal.

11. A method according to Claim 9, wherein the DCI is a downlink grant which schedules the transmission of the uplink signal in response to the communications device receiving downlink data from the wireless communications network.

12. A method according to Claim 9, wherein the DCI is a group common DCI, GC-DCI, wherein the GC-DCI is also transmitted by the wireless communications network to one or more other communications devices.

13. A method according to Claim 9, wherein receiving the DCI comprises the communications device blindly decoding for a DCI of a first size and for a DCI of a second size, wherein the dynamic downlink indication received within a DCI of the first size indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and wherein the dynamic downlink indication received within a DCI of the second size indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

14. A method according to Claim 9, wherein if the DCI has a first format, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the DCI has a second format, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

15. A method according to Claim 9, wherein the DCI comprises an indicator, and wherein if the indicator indicates the first uplink transmission mode, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the indicator indicates the second uplink transmission mode, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

16. A method according to Claim 9, wherein if an identifier of the DCI is equal to a first identifier, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode, and if the identifier of the DCI is equal to a second identifier, the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode.

17. A method according to Claim 9, wherein the DCI comprises an indication of a transmit precoding matrix index, TPMI, field capable of indicating a set of TPMI values, wherein a first TPMI value indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode by performing precoding of the uplink signal in accordance with second precoding weights independently determined by the communications device, and wherein one or more other TPMI values to the first TPMI value each indicate that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode by performing precoding of the uplink signal in accordance with first precoding weights associated with that TPMI value.

18. A method according to Claim 9, wherein the DCI comprises an indication of a sounding reference signal resource indicator, SRI, field capable of indicating a set of SRI values, wherein a first SRI value indicates that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode by performing transmission of the uplink signal using a second uplink beam independently determined by the communications device, and wherein one or more other SRI values to the first SRI value each indicate that the communications device is to transmit the uplink signal to the wireless communications network in accordance with the first uplink transmission mode by performing transmission of the uplink signal using a first uplink beam associated with that SRI value.

19. A method according to Claim 1, wherein the dynamic downlink indication is received from the wireless communications network within a random access response, RAR, message, wherein the RAR is received in response to the communications device transmitting a random access, RACH, preamble to the wireless communications network to initiate a RACH procedure.

20. A method according to Claim 1, comprising receiving, from the wireless communications network, an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on the received channel adjustment factor.

21. A method according to Claim 20, wherein the indication of the channel adjustment factor is received from the wireless communications network within a DCI.

22. A method according to Claim 20, wherein the indication of the channel adjustment factor is received from the wireless communications network within RRC signalling.

23. A method according to Claim 1, comprising receiving, from the wireless communications network, an indication of a set one or more downlink reference signals, DL RS, for which the communications device is not to assume channel reciprocity.

24. A method according to Claim 23, wherein if the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on one or more DL RS which are not part of the indicated set of DL RS.

25. A method according to Claim 23, comprising receiving, from the wireless communications network for each of the indicated set of DL RS, an indication of a channel adjustment factor between a first antenna panel of an infrastructure equipment of the wireless communications network and a second antenna panel of the infrastructure equipment, wherein if the communications device determines that it is to transmit the uplink signal to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on a DL RS of the indicated set of DL RS in combination with the received channel adjustment factor for that DL RS.

26. A method according to Claim 1, wherein if the communications device determines that it is to transmit the uplink signal to the wireless communications network in accordance with the second uplink transmission mode, the second uplink transmission mode comprises performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device without assuming channel reciprocity between the transmission of the uplink signal and reception of one or more DL RS from the wireless communications network.

27. A communications device comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to determine that the communications device has an uplink signal to transmit to the wireless communications network, to determine, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to transmit the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode.

28. Circuitry for a communications device, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to determine that the communications device has an uplink signal to transmit to the wireless communications network, to determine, based on either a parameter of the uplink signal or a dynamic downlink indication received from the wireless communications network, whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to transmit the uplink signal to the wireless communications network in accordance with the determined one of the first uplink transmission mode and the second uplink transmission mode.

29. A method of operating an infrastructure equipment forming part of a wireless communications network, the method comprising determining that infrastructure equipment is to receive an uplink signal from a communications device, transmitting, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and receiving the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

30. A method according to Claim 29, wherein the first uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with first parameters indicated by the infrastructure equipment, wherein the second uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

31. A method according to Claim 30, wherein the first parameters are indicated in a codebook transmitted by the infrastructure equipment to the communications device, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

32. A method according to Claim 31, comprising determining, if the communications device is not able to dynamically determine whether to transmit the uplink signal in accordance with the codebook based uplink transmission mode or the noncodebook based uplink transmission mode and if the uplink signal is to be transmitted by the communications device within one or more sub-band full duplex, SBFD, symbols, that the infrastructure equipment is to receive the uplink signal from the communications device in accordance with the codebook based uplink transmission mode.

33. A method according to Claim 29, wherein the dynamic downlink indication indicates that the uplink signal is to be transmitted in accordance with either the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and wherein the infrastructure equipment determines that the uplink signal is to be transmitted in accordance with a preconfigured one of the first uplink transmission mode or the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, and wherein the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

34. A method according to Claim 29, wherein the dynamic downlink indication indicates that the uplink signal is to be transmitted in accordance with the first uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a first type, and the uplink signal is to be transmitted in accordance with the second uplink transmission mode if the one or more symbols in which the uplink signal is to be transmitted are of a second type, wherein the first type is one of SBFD or non-SBFD and the second type is the other of SBFD and non-SBFD.

35. A method according to Claim 29, wherein the dynamic downlink indication is transmitted to the communications device within downlink control information, DCI.

36. A method according to Claim 35, wherein the DCI is an uplink grant which schedules the transmission of the uplink signal.

37. A method according to Claim 35, wherein the DCI is a downlink grant which schedules the transmission of the uplink signal in response to the infrastructure equipment transmitting downlink data to the communications device.

38. A method according to Claim 35, wherein the DCI is a group common DCI, GC-DCI, wherein the GC-DCI is also transmitted by the infrastructure equipment to one or more other communications devices.

39. A method according to Claim 35, wherein if the DCI has a first size, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the DCI has a second size, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

40. A method according to Claim 35, wherein if the DCI has a first format, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the DCI has a second format, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

41. A method according to Claim 35, wherein the DCI comprises an indicator, and wherein if the indicator indicates the first uplink transmission mode, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the indicator indicates the second uplink transmission mode, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

42. A method according to Claim 35, wherein if an identifier of the DCI is equal to a first identifier, the uplink signal is to be transmitted in accordance with the first uplink transmission mode, and if the identifier of the DCI is equal to a second identifier, the uplink signal is to be transmitted in accordance with the second uplink transmission mode.

43. A method according to Claim 35, wherein the DCI comprises an indication of a transmit precoding matrix index, TPMI, field capable of indicating a set of TPMI values, wherein a first TPMI value indicates that the uplink signal is to be transmitted in accordance with the second uplink transmission mode by the communications device performing precoding of the uplink signal in accordance with second precoding weights independently determined by the communications device, and wherein one or more other TPMI values to the first TPMI value each indicate that the uplink signal is to be transmitted in accordance with the first uplink transmission mode by the communications device performing precoding of the uplink signal in accordance with first precoding weights associated with that TPMI value.

44. A method according to Claim 35, wherein the DCI comprises an indication of a sounding reference signal resource indicator, SRI, field capable of indicating a set of SRI values, wherein a first SRI value indicates that the uplink signal is to be transmitted in accordance with the second uplink transmission mode by the communications device performing transmission of the uplink signal using a second uplink beam independently determined by the communications device, and wherein one or more other SRI values to the first SRI value each indicate that the uplink signal is to be transmitted in accordance with the first uplink transmission mode by the communications device performing transmission of the uplink signal using a first uplink beam associated with that SRI value.

45. A method according to Claim 29, wherein the dynamic downlink indication is transmitted to the communications device within a random access response, RAR, message, wherein the RAR is received in response to the infrastructure equipment receiving a random access, RACH, preamble from the communications device to initiate a RACH procedure.

46. A method according to Claim 29, comprising transmitting, to the communications device, an indication of a channel adjustment factor between a first antenna panel of the infrastructure equipment and a second antenna panel of the infrastructure equipment, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on the indicated channel adjustment factor.

47. A method according to Claim 46, comprising determining the channel adjustment factor based on a difference between a first signal quality of first reference signals and a second signal quality of second reference signals, wherein the infrastructure equipment had transmitted the first reference signals via the first antenna panel to the communications device and received an indication of the first signal quality from the communications device, and wherein the infrastructure equipment had received the second reference signals from the communications device via the second antenna panel and performed measurements on the second reference signals to determine the second signal quality.

48. A method according to Claim 46, wherein the channel adjustment factor is preconfigured and known to the infrastructure equipment.

49. A method according to Claim 46, wherein the indication of the channel adjustment factor is transmitted to the communications device within a DCI.

50. A method according to Claim 46, wherein the indication of the channel adjustment factor is transmitted to the communications device within RRC signalling.

51. A method according to Claim 29, comprising transmitting, to the communications device, an indication of a set one or more downlink reference signals, DL RS, for which the communications device is not to assume channel reciprocity.

52. A method according to Claim 51, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on one or more DL RS which are not part of the indicated set of DL RS.

53. A method according to Claim 51, comprising transmitting, to the communications device for each of the indicated set of DL RS, an indication of a channel adjustment factor between a first antenna panel of the infrastructure equipment and a second antenna panel of the infrastructure equipment, wherein if the uplink signal is to be transmitted to the infrastructure equipment in accordance with the second uplink transmission mode, the second uplink transmission mode comprises the communications device performing transmission of the uplink signal in accordance with second parameters independently determined by the communications device based on a DL RS of the indicated set of DL RS in combination with the indicated channel adjustment factor for that DL RS.

54. An infrastructure equipment forming part of a wireless communications network, the infrastructure equipment comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to determine that infrastructure equipment is to receive an uplink signal from a communications device, to transmit, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to receive the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

55. Circuitry for an infrastructure equipment forming part of a wireless communications network, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to determine that infrastructure equipment is to receive an uplink signal from a communications device, to transmit, to the communications device, a dynamic downlink indication which indicates whether the communications device is to transmit the uplink signal to the wireless communications network in accordance with a first uplink transmission mode or a second uplink transmission mode, and to receive the uplink signal from the communications device in accordance with the indicated one of the first uplink transmission mode and the second uplink transmission mode.

56. A method of operating an infrastructure equipment forming part of a wireless communications network, the method comprising transmitting, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

57. A method according to Claim 56, comprising transmitting, to the communications device, a second indication via radio resource control, RRC, signalling, the second indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a second type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the second type is the other of SBFD or non-SBFD.

58. A method according to Claim 56, wherein the first uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with first parameters indicated by the infrastructure equipment, wherein the second uplink transmission mode comprises the uplink signal being transmitted by the communications device in accordance with second parameters independently determined by the communications device, and wherein the first parameters comprise first precoding weights and/or a first uplink beam and the second parameters comprise second precoding weights and/or a second uplink beam.

59. A method according to Claim 58, wherein the first parameters are indicated in a codebook transmitted by the infrastructure equipment to the communications device, the codebook indicating multiple sets of parameters including the first parameters, and wherein the first uplink transmission mode is a codebook based uplink transmission mode and the second uplink transmission mode is a non-codebook based uplink transmission mode.

60. An infrastructure equipment forming part of a wireless communications network, the infrastructure equipment comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to transmit, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

61. Circuitry for an infrastructure equipment forming part of a wireless communications network, the circuitry comprising transceiver circuitry configured to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the transceiver circuitry to transmit, to a communications device, a first indication via radio resource control, RRC, signalling, the first indication indicating, if the communications device has an uplink signal to be transmitted to the infrastructure equipment in one or more symbols of a first type, whether the communications device is to transmit the uplink signal to the infrastructure equipment in accordance with a first uplink transmission mode or a second uplink transmission mode, wherein the first type is one of sub-band full duplex, SBFD, or non-SBFD.

62. A wireless communications system comprising a communications device according to Claim 27 and an infrastructure equipment according to Claim 54 or Claim 60.

63. A computer program comprising instructions which, when loaded onto a computer, cause the computer to perform a method according to Claim 1, Claim 29, or Claim 56.

64. A non-transitory computer-readable storage medium storing a computer program according to Claim 63.