WO2024170569A1

WO2024170569A1 - Methods, communications devices, relay nodes, and network infrastructure equipment

Info

Publication number: WO2024170569A1
Application number: PCT/EP2024/053627
Authority: WO
Inventors: Yuxin Wei; Vivek Sharma; Hideji Wakabayashi; Yassin Aden Awad
Original assignee: Sony Europe BV United Kingdom Branch; Sony Group Corp
Current assignee: Sony Europe BV United Kingdom Branch; Sony Group Corp
Priority date: 2023-02-15
Filing date: 2024-02-13
Publication date: 2024-08-22
Anticipated expiration: 2025-08-15

Abstract

Methods, communications devices, relay node, and infrastructure equipment for establishing and managing a multipath connection between a communications device and an infrastructure equipment. The multipath connection includes a direct radio connection between the communications device and an infrastructure equipment, and an indirect connection including a sidelink connection between the communications device and a relay node, where the relay node has a connection to the infrastructure equipment. Direct radio connections and sidelink connection can be established, released and handed over using RRC signaling, while MAC/PHY or RRC signaling may be used for management of the multipath connection.

Description

METHODS, COMMUNICATIONS DEVICES, RELAY NODES, AND NETWORK INFRASTRUCTURE EQUIPMENT

The present application claims the Paris Convention priority of European patent application EP23156887.4, filed 15 February 2023, the contents of which are hereby incorporated by reference.

BACKGROUND

Field of Disclosure

The present disclosure relates to a communications device, relay nodes, network infrastructure equipment, and methods of operating communications devices, relay nodes and infrastructure equipment, for establishing and managing a multipath connection between a communications device and a network infrastructure equipment.

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.

Modern 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.

Wireless communications networks are expected to routinely and efficiently support communications with an ever-increasing range of devices associated with a wide range of data traffic profiles and types. For example, it is expected that wireless communications networks efficiently support communications with devices including reduced complexity devices, machine type communication (MTC) devices, high resolution video displays, virtual reality headsets 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 I characteristics depending on the application(s) it is running. For example, different consideration 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 a desire for current generation wireless communications networks, for example those referred to as 5G or new radio (NR) systems I new radio access technology (RAT) systems, as well as future iterations I 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.

One example of a new service is referred to as Ultra Reliable Low Latency Communications (URLLC) services which, as its name suggests, requires that a data unit or packet be communicated with a high reliability and with a low communications delay. Another example of a new service is enhanced Mobile Broadband (eMBB) services, which are characterised by a high capacity with a requirement to support up to 20 Gb/s. URLLC and eMBB type services therefore represent challenging examples for both LTE type communications systems and 5G/NR communications systems.

5G NR has continuously evolved and the current work plan includes 5G-NR-advanced in which some further enhancements are expected, especially to support new use- cases/scenarios with higher requirements. The desire to support these new use-cases and scenarios gives rise to new challenges for efficiently handling communications in wireless communications systems that need to be addressed.

SUMMARY OF THE DISCLOSURE

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

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;

Figures 4A and 4B illustrate example implementations of multipath arrangements for a UE connected to a gNB via a direct path and a sidelink path via a relay node. Figure 5 illustrates an example approach for adding a sidelink connection between a remote UE and a gNB.

Figure 6 illustrates an example approach for adding a direct connection between a remote UE and a gNB, where a sidelink connection already exists.

Figure 7 illustrates an example approach for releasing a sidelink between a remote UE and a relay node used for a sidelink connection.

Figure 8 illustrates an example approach for releasing a direct connection between a remote UE and a gNB, where a sidelink connection between the remote UE and the gNB, via a relay node, exists.

Figure 9 illustrates an example approach for handover of a direct connection between a remote UE and different cells of a gNB, where a sidelink connection between the UE and the gNB via a relay node exists.

Figure 10 illustrates an example approach for handover of a sidelink (for a sidelink channel) between a remote UE and a source relay node to a target relay node.

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 or mobile terminals (MT) 4 within their respective coverage areas 3 via a radio downlink. Data is transmitted from communications devices 4 to the base stations 1 via a radio uplink. 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. The communications or terminal devices 4 may also be referred to as mobile stations, user equipment (UE), user terminal, mobile radio, communications device, 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 (NR))

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 (Dlls) 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 I TRPs 10 may be broadly considered to provide functionality corresponding to the base stations 1 of Figure 1. The term network infrastructure equipment I 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 I central unit and I or the distributed units I 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 I 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 I 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 I access nodes and a communications device, wherein the specific nature of the network infrastructure equipment I 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 I 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 I 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 circuit 49, a receiver circuit 48 and a controller circuit 44 which is configured to control the transmitter circuit 49 and the receiver circuit 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 circuit 30 and received by the receiver circuit 48 in accordance with the conventional operation.

The transmitter circuits 30, 49 and the receiver circuits 32, 48 (as well as other transmitters, receivers and transceivers described in relation to examples and embodiments of the present disclosure) may include radio frequency filters 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 controller circuits 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 transmitters, 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) I circuitry I chip(s) I chipset(s). As will be appreciated the infrastructure equipment I TRP I base station as well as the UE I 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 F1 interface which can be a physical or a logical interface. The F1 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 TRP10 to the DU 42 and the F1 interface 46 from the DU 42 to the CU 40.

Multipath Using Sidelink Relay

As current and future generations of wireless communication networks continue to take shape, there is a general desire to improve network traffic flow rates, improve redundancy and avoid drops in service, for example in order to support URLLC services. One technique existing communication network implementations may provide to attempt address these concerns is the capability for a UE to connect to multiple gNBs/eNBs of a wireless communications network simultaneously. This is known as Dual Connectivity (DC) and utilises radio resources provided by two distinct schedulers (i.e. Media Access Control (MAC) entities) located in two different radio access network (RAN) nodes (i.e. different gNBs/eNBs), connected via a nonideal backhaul. This approach has since been expanded to allow a UE to connect to both LTE and 5G/NR nodes, known as Multi-Radio Dual Connectivity (MR-DC). Accordingly, networks can communicate with the wireless communications network using different links to different Radio Access Network (RAN) nodes, and the network can steer traffic between the two connections based on various factors, such as network load, radio conditions, and Quality of Service (QoS) requirements.

DC allows for a smooth transition from LTE to 5G by leveraging the existing LTE infrastructure and ensuring that the UE has a stable connection even in areas where 5G coverage is not yet available. It also provides better network performance and improved user experience by allowing the UE to take advantage of the best available connection in terms of speed, latency, and reliability. In addition, some existing implementations provide for sidelink connections between UEs. A sidelink connection is a direct communication link established between two or more User Equipment (UE) devices without going through a cellular network. Sidelink communication can be used in various applications, such as vehicle-to-vehicle (V2V) communication, device-to- device (D2D) communication, and machine-type communications (MTC). The sidelink communication enables UEs to exchange data directly without relying on a centralized infrastructure, thereby improving communication efficiency and reducing latency.

Another technique existing communication network implementations may provide to address this is for carrier aggregation (CA), whereby traffic between a UE and a RAN node may be transmitted using multiple carrier frequencies in a single data stream. This allows the network to provide more bandwidth to the end-user, resulting in faster download and upload speeds, lower latency, and improved overall network capacity. In 3GPP networks, carrier aggregation can be achieved by combining different frequency bands, such as LTE in the 700 MHz and 1700 MHz bands, or combining different types of LTE technologies, such as LTE-Advanced and LTE-Advanced Pro. The use of carrier aggregation also allows for better spectral efficiency, which means that the same amount of data can be transmitted using less spectrum.

This results in better network coverage, increased capacity, and improved overall network performance .Overall, carrier aggregation is an important technology for mobile network operators as it helps to meet the growing demand for mobile data services and provides a more efficient use of the available spectrum resources. However, Carrier Aggregation does not improve redundancy, as a single path between a UE and a RAN node is used.

Therefore, as can be seen, existing network implementations do not allow UEs to connect to the same gNB using different paths. Such an implementation would provide redundancy and improve traffic flow rates between a UE and gNB.

Figure 4A shows a first example implementation of multipath using a sidelink relay. In Figure 4A, a UE 410 is connected to a gNB 420 via a Uu link 440, which is a direct radio interface between a UE and a gNB (or other infrastructure equipment or base station, such as those described in relation to Figures 1-3), and may exchange uplink (UL) and/or downlink (DL) traffic with the gNB 420 via the Uu link 440. In addition, the gNB 420 is also connected to a Layer-2 UE-to-network relay 430 via a Uu link 445, and the UE 410 is connected to the network relay 430 via a sidelink 450 (e.g. a PC5 link), which is a direct radio interface between a UE and another UE or relay node. In this manner, the UE 410 may additionally exchange UL and/or DL traffic with the gNB 420 via the sidelink 450 and Uu link 445, collectively known as an indirect connection between the UE 410 and the gNB 420.

As such, the UE 410 may exchange traffic with the same gNB 420 using multiple different links/connections: a direct link and an indirect link. Figure 4B shows an alternative example implementation of multipath using a sidelink relay. The components and links are identical to Figure 4B, except that the network relay 430 of Figure 4A is replaced with a relay UE 435. The relay UE 435 also has a Uu link 445 with the gNB 420 and a sidelink 450 (i.e. UE-to-UE link such as a PC5 link, WiFi link, or Bluetooth link) with the UE 410. The relay UE 435 may in some cases be similar to UE 410, and as such the UE-to-UE connection 450 between the UE 410 and the relay UE 435 may utilise a number of possible communication protocols, such as 4G/NR/5G (as discussed in relation to Figures 1-3, or other, non-3GPP protocols such as Bluetooth or WiFi). The techniques of the present disclosure may be generally considered to be applicable to the arrangements in both Figures 4A and 4B, unless otherwise stated.

Figure 5 illustrates an arrangement for a remote UE 510 (such as UE 410), a gNB 520 (such as gNB 420), and a relay node 530 (such as network relay 430 or relay UE 435) for adding an sidelink 450 between the remote UE 510 and relay node 430 (forming part of an indirect connection between the remote UE 510 and the gNB 520), where an existing Uu link 440 exists between the remote UE 510 and gNB 520. In step 541 , the Uu link 440 is established between the remote UE 510 and the gNB 520, whereby data may be exchanged between the remote UE 510 and the gNB 520 via this link. Using the Uu link 440, the gNB 542 may configure 542 the remote UE 510 to provide the gNB 520 with a measurement report, traffic demand or predicted traffic volume. In other words, the gNB 520 may transmit a measurement configuration message 542 to the remote UE 510, which may configure the remote UE 510 to provide measurement data 543 (e.g. historical, current or predicted traffic volume, a buffer status report, or a signal measurement report for the remote UE’s 510 signal strength for the gNB 520 or any measurements on the candidate relay nodes). Based on this measurement data 543, the gNB 520 may determine that a sidelink should be established for the remote UE 510 in order to provide an indirect link between the remote UE 510 and the gNB 520. For example, the gNB 520 may determine based on a signal measurement report for the remote UE (e.g. based on RSSI or RSRP measurements performed by the UE) that the UE has low signal strength with the gNB 520 and thus that a sidelink should be established to provide redundancy and improve data exchange between the remote UE 510 and the gNB 520. Additionally or alternatively, the gNB 520 may determine that the quantity of traffic between the remote UE 510 and gNB 520 is expected to be high in the future, and thus that a sidelink should be established to cope with this increased traffic demand. However, it should be appreciated that the decision to establish a sidelink for the remote UE 510 may be based on the measurement data 543, or on a number of additional or alternative factors. As such, the gNB 520 may determine that the sidelink for the remote UE 510 should be established without the transmission of the measurement configuration message 542 and/or the measurement data 543.

After determining that the sidelink should be established for the remote UE 510, the gNB identifies that a relay node 530 for the sidelink connection 450. The relay node 530 may be, for example, be a network relay 430, or a relay UE 435. The identification of the relay node 530 may be based, for example, on a measured signal strength (e.g. RSSI or RSRP measurements) between potential relay nodes and the remote UE 510 and gNB 520. In some cases, the gNB 520 may already have an existing Uu link 445 to the relay node 430, or a new Uu link 445 may be established. In order to establish the sidelink connection, the gNB 520 transmits a first Radio Resource Control (RRC) reconfiguration message 544 to the relay node 530. The first RRC reconfiguration message 544 may include configuration information for the sidelink connection 450 (and/or the indirect connection as a whole), including e.g. sidelink channel configurations for establishing the sidelink 450 between the remote UE 510 and the relay node 530, and an identifier of the remote UE 510. The first RRC reconfiguration message 544 may also include information for setting up a new Data Radio Bearer (DRB) for the Uu link 445 for sidelink traffic (or traffic for the indirect connection), however this information may alternatively be included in a different reconfiguration message. The new DRB for the Uu link 445 may depend on whether a 1 :1 , N:1 or 1 :N configuration is supported by the remote relay node 530 and/or gNB 520, over the Uu link 445 between the gNB 520 and relay node 530, for the traffic destined for the remote UE 510.

In addition to the first RRC reconfiguration message 544, the gNB 520 transmits a second RRC reconfiguration message 545 to the remote UE 510. The second RRC reconfiguration message 545 may include the configuration information for the sidelink connection 450 (and/or the indirect connection as a whole), including e.g. sidelink channel configurations for establishing the sidelink 450 between the remote UE 510 and the relay node 530, and an identifier for the relay node 530. Based on receiving the RRC reconfiguration messages, the remote UE 510 and the relay node 530 may establish 546 a sidelink 450 e.g. using the configuration information and identifiers included in the RRC reconfiguration messages 544, 545. After establishing 546 the sidelink 450, the remote UE 510 and/or relay node 530 may transmit an RRC reconfiguration complete message 547, indicating that the sidelink 450 has been established, and is therefore available for use in an indirect connection between the remote UE 510 and gNB 520. The RRC reconfiguration complete message 547 may be transmitted via the sidelink connection, or via the direct Uu link 440 between the remote UE 510 and the gNB 520.

Accordingly, the process shown in Figure 5 allows an indirect connection between the remote UE 510 and gNB 520 (via the relay node 53) to be established, to enable a multipath connection between the remote UE 510 and gNB 520. In other words, the remote UE 510 is connected to the gNB 520 by two distinct, non-overlapping radio paths. This provides improved redundancy and throughput, as both paths may be used to transmit both UL and DL traffic between the remote UE 510 and the gNB 520.

In the resultant multipath arrangement, multiple scheduler implementations are possible. That is a single scheduler at the gNB 520 may dictate traffic flow for both paths. In other words, the gNB 620 may maintain a single MAC entity for the remote UE 510 for both paths (in a similar manner to Carrier Aggregation). Furthermore, the remote UE 510 may maintain a separate MAC entity for each of the paths (in a similar manner to Dual Connectivity), where the Uu connection is the master node (MN), while the sidelink is the secondary node (SN). Alternatively, in some examples the remote UE 510 may maintain a single MAC entity for both paths.

The process shown in Figure 5 may be repeated such that the remote UE 510 may establish multiple indirect connections to the gNB 520 via multiple sidelink connections and relay nodes. In other words, the remote UE 510 may establish sidelinks with multiple relay nodes, which each have a Uu connection with the gNB 520. As such, a remote UE 510 may have multiple non-overlapping indirect connections to the gNB 520. This further improves redundancy and throughput. Furthermore, it should be appreciated that the relay node 530 may have sidelinks to multiple different remote UEs 510. As such, when transmitting data to the relay node 530 destined for a particular remote UE, the gNB 520 may include an identifier for the particular remote UE to allow the relay node 530 to route the data to the correct remote UE.

Once there is both a direct Uu connection and an indirect connection via the relay node 530 between the remote UE 510 and the gNB 520, the flow of traffic between the remote UE 510 and gNB 520 using the two paths (the direct Uu path and indirect path via the relay node 530), may be configured by the gNB 520. That is, the Packet Data Convergence Protocl (PDCP) entity in the CU 40 of the gNB 520 splits DL traffic between the gNB’s Uu link 440 with the remote UE 510 and the gNB’s Uu link 445 with the relay node 530. In addition, the remote UE 510 splits UL traffic between the remote UE’s 510 Uu link 440 with the gNB 520 and the remote UE’s 510 sidelink 450 with the relay node 530. The ratio at which traffic is split between the direct Uu link and the sidelink may be predetermined and signalled to the remote UE 510 (for example in the second RRC reconfiguration message 545, or in separate signalling). Traffic that is split across the multiple paths may belong to a single Protocol Data Unit (PDU) session/DRB, or to separate PDU sessions/DRBs. In this information may be provided to the remote UE 510 and relay node 530 by the gNB 520.

The ratio at which traffic is split between the direct Uu path and the sidelink connection may be dynamically changed, for example in response to changing traffic demands and/or changes in signal strength on any of the links between the remote UE 510, relay node 530 and gNB 520. Dynamic changes to the multipath configuration, such as changes to the traffic split ratio, may be signalled to the remote UE 510 by the gNB 520 using MAC layer and/or physical layer (MAC/PHY) signalling (via the llu link 440 or the indirect connection). For example, an initial traffic split ratio may be included in the second RRC reconfiguration message 545, however the gNB 520 may use MAC/PHY signalling to dynamically change the ratio of UL traffic assigned to the llu (direct) link 440 and the sidelink 450 by the remote UE 510, for example in response to changing traffic demands or signal strengths. The use of MAC/PHY signalling for dynamic changes to the multipath configuration provides a fast and bandwidth efficient (compared to RRC) means of changing the multipath configuration (e.g. changing the traffic split ratio), while using RRC signalling for establishing multipath (as discussed above), allows a greater quantity of data (i.e. configuration information) to be transmitted in order to establish new connections, while also providing greater security as compared to MAC/PHY signalling. However, in some cases RRC signalling may be used for signalling dynamic changes to the multipath configuration.

While the multipath traffic split ratio for DL and UL may be predetermined by the gNB 520 and also dynamically modified by the gNB 520 (and signalled to the remote UE 510 (via the direct link or the indirect link) for UL traffic), as described above, the multipath traffic split ratio may also be determined by the UE 510 autonomously (i.e. without specific signalling from the gNB 520). Furthermore, the remote UE 510 may in some cases modify the traffic split ratio for UL traffic without instruction from the gNB 510. That is, the remote UE 510 (or an application on the remote UE 510) may be aware of radio conditions and may therefore wish to send packets via a strong link, rather than a weak link as the predefined traffic split ratio may require. Furthermore, if particular radio access technologies, such as FR2, are used for the sidelink connection 450, then UL coverage for the remote UE 510 may be smaller than DL coverage (due to limited UE power and beamforming constraints). Multipath may offer an opportunity to allow more flexibility for UL traffic. That is, if the sidelink connection 450 is more reliable than the direct Uu connection 440, the remote UE 510 may be permitted to violate the predetermined traffic split ratio and, for example, push a greater percentage of its UL traffic via the relay node 530 (i.e. via the sidelink 450). As such, a UE application may be allowed to send data for a particular service via a particular link. The relay node 530 may request a buffer status report (BSR) for the sidelink connection from the remote UE 510 and may therefore adjust its own BSR (when reporting to the gNB 520) to accommodate the expected adjusted data rate via the sidelink connection. A buffer status report is an indication of the content (e.g. quantity and/or type of data) of a buffer for a logical channel group.

While Figure 5 illustrates the examples whereby a new sidelink 450 is established to provide an indirect connection for a UE having an existing Uu connection to a gNB, Figure 6 illustrates an examples where a new Uu connection 440 between a remote UE 610 and a gNB 620 is established, for cases where there is an existing indirect connection between the remote UE 610 and the gNB 620 via a relay node 630 (including a sidelink450 to a relay node 630 from the remote UE 610 and a Uu connection 445 from the relay node 530 to the gNB 620). At step 641 , an indirect connection between the remote UE 610 and the gNB 620 via the relay node 630 is established, using a sidelink connection 450. In addition, the gNB 620 and remote UE 610 may exchange a measurement report request 642 and/or measurement data 643 (over the sidelink) in the same manner as described above in relation to Figure 5, in order for the gNB 620 to determine that a multipath connection should be established. In other words, the gNB 620 may determine that a new direct Uu connection 440 between the gNB 620 and the remote UE 610 should be established.

After determining that a new direct Uu connection 440 between the gNB 620 and the remote UE 610 should be established, the gNB 620 transmits an RRC reconfiguration message 644 to the UE 610, via the sidelink (i.e. via the indirect connection). The RRC reconfiguration message 644 instructs the UE 610 to initiate a Random Access Channel (RACH) procedure 645 with the gNB 610. The RRC reconfiguration message 644 may also include multipath configuration information, such as a traffic split ratio, as well as cell configurations for the llu link to be added. After completing the RACH procedure 645, thereby establishing a new direct llu connection 440 between the gNB 620 and the remote UE 610, the UE 646 may transmit an RRC reconfiguration complete message 646 to the gNB 620 (via the direct Uu link or via the sidelink) confirming that the new direct Uu link has been established, and may confirm that multipath has been configured according to the RRC reconfiguration message 644.

The RRC reconfiguration message 644 may indicate that the new direct Uu connection 440 should be added as a primary cell (Pcell) of a master node (MN) for the remote UE 610 (in a similar manner to MNs for Dual Connectivity). As such, the sidelink connection 450 may be a secondary cell (Scell) of the main node (MN) for the remote UE 610 (in a similar manner to SNs for Dual Connectivity). In some examples, the remote UE 610 have already have an existing Uu connection 440 with the gNB 620 when the new Uu connection is established via the process of Figure 6. The existing Uu connection may be inactive, such that no data is transferred via the existing Uu link. This existing Uu connection may be a Pcell of the MN for the remote UE 610, such that the sidelink is an Scell of the MN for the remote UE 610 and the new Uu connection is added as an Scell of the MN for the remote UE 610. In some examples, the new Uu connection may be added as a Pcell of the MN for the remote UE 610, while the existing Uu connection may be reconfigured as an Scell of the MN for the remote UE 610.

Figures 5 and 6 discussed above illustrate approaches for adding new connections for multipath, however in some cases a UE or gNB may wish to remove an existing multipath connection. Figure 7 illustrates an approach for releasing an existing sidelink 450 between a remote UE 710 and a relay 730, which serves as part of an indirect connection between the remote UE 710 and a gNB 730. The remote UE 710, gNB 720 and relay node 730 may be substantially similar to the remote UE 510, 610, gNB 520, 620, and relay node 530, 630 of Figures 5 and 6. In the approach of Figure 7, the gNB 720 may transmit a measurement configuration message 741 to the remote UE 710 and in reply receive measurement data 742 from the remote UE 710. This process may be substantially similar to that described above in relation to Figure 5, and the measurement configuration message 741 and measurement data 742 may each be transmitted over the sidelink or the direct Uu connection. Based on this measurement process, the gNB 720 may determine that the sidelink connection (i.e. the indirect connection) should be released. For example, the gNB 720 may determine that the signal quality of the sidelink 450 may be low (i.e. below a particular threshold), or that the quantity of traffic to be transmitted between the remote UE 710 and gNB 720 is expected to be comparatively low, such that the sidelink connection 450 is not required.

After determining that the sidelink 450 should be released, the gNB 720 transmits a first RRC reconfiguration message 743 to the relay node 530, directing (i.e. instructing or indicating) the relay node 530 to release the sidelink 450 to the remote UE 710. The first RRC reconfiguration message 743 may indicate details of the sidelink to be released, such as an identifier for the remote UE 710 and/or the sidelink, and modifications to (or deletion of) multipath configuration information. The first RRC reconfiguration message 743 may direct the relay node 730 to release a DRB configuration for the sidelink . In addition, the gNB 720 transmits a second RRC reconfiguration message 744 to the remote UE 710, directing the remote UE 710 to release the sidelink to the relay node 530. The second RRC reconfiguration message 744 may indicate details of the sidelink to be released, such as an identifier for the relay node 730 and/or the sidelink, and modifications to (or deletion of) multipath configuration information. Based on the RRC reconfiguration messages 743, 744, the remote UE 710 and relay node 730 both or either one initiates to release the sidelink. The remote UE 710 (and/or the relay node 730) may then transmit an RRC reconfiguration complete message 746 to the gNB 720 indicating that the remote UE 710 (and/or the relay node 730) has been reconfigured as directed, and has released the sidelink. Accordingly, a multipath arrangement may be modified to a single llu connection arrangement by releasing the sidelink.

Figure 8 illustrates an approach for releasing an existing llu connection between a remote UE 810 and a gNB 820, when an indirect connection between the remote UE 810 and gNB 820 via a relay node 830 using a sidelink exists. The remote UE 810, gNB 820 and relay node 830 may be substantially similar to the remote UE 510, 610, 710, gNB 520, 620, 720, and relay node 530, 630, 730 of Figures 5, 6 and 7 described above. In the approach of Figure 8, the gNB 820 may transmit a measurement configuration message 841 to the remote UE 810 and in reply receive measurement data 842 from the remote UE 810. This process may be substantially similar to that described above in relation to Figure 5, and the measurement configuration message 841 and measurement data 842 may each be transmitted over the sidelink or the direct Uu connection. Based on this measurement process, the gNB 820 may determine that the direct connection (and therefore the Uu connection) should be released. For example, the gNB 820 may determine that the signal quality of the Uu may be low (i.e. below a particular threshold), or that the quantity of traffic to be transmitted between the remote UE 810 and gNB 820 is expected to be comparatively low, such that the direct connection is not required.

After determining that the Uu connection should be released, the gNB 820 transmits an RRC message 843 to the remote UE 810. The RRC message 843 may be an RRC reconfiguration message directing (i.e. instructing or indicating) the remote UE 810 to release (i.e. remove) the Uu connection to the gNB 820, and the RRC reconfiguration message may include connection details to release for the Uu connection between the UE 810 and the gNB 820. The UE 810 then releases the Uu connection, and may subsequently transmit an RRC reconfiguration complete message to the gNB 820 confirming that the Uu connection has been released. This example is of particular use in examples where the remote UE 810 has another Uu connection to the gNB as a Pcell of the MN for the remote UE 810. That is, if the remote UE 810 has both a Pcell and an Scell Uu connection and the remote UE 810 is to maintain a Uu connection as Pcell, the remote UE 810 may release the Scell Uu connection. Alternatively, the RRC message 843 may be an RRCRelease message directing the UE 810 to change the Uu connection to an Idle/inactive state. In this way, the Uu connection may be maintained as a Pcell for the MN of the remote UE 810, while being set to an Idle/inactive state, meaning the sidelink is maintained as an Scell. Alternatively, the Uu connection may be released as the Pcell of the MN, such that there is no multi-path for the remote UE 810, and thus that the remote UE 810 only connects to the gNB 820 via the indirect link (i.e. via the sidelink).

While Figures 5-8 discussed above primarily relate to establishing and releasing (i.e. removing) sidelink and Uu connections, in some cases a gNB may deactivate a link (i.e. set the link to a deactiveated state) or reactivate (i.e. activate) an deactivated link (e.g. a link that has been deactivated). To achieve deactivation of the sidelink, the gNB may send a deactivation message to the remote UE. This deactivation message may indicate that the sidelink is deactivated; whether the sidelink is deactivated for only UL traffic, only DL traffic, or both UL and DL traffic; and/or an ID for the relay node. The gNB may also send a deactivation message to the relay node. This deactivation message may indicate that the sidelink is deactivated; whether the sidelink is deactivated for only UL traffic, only DL traffic, or both UL and DL traffic; and/or an ID for the remote UE. Similarly, to achieve (re)activation of the sidelink, the gNB may send a (re)activation message to the remote UE. The (re)activation message may indicate that the sidelink is (re)activated; whether the sidelink is (re)activated for only UL traffic, only DL traffic, or both UL and DL traffic; an ID for the relay node; and/or a traffic split ration between the direct llu connection and the sidelink. The gNB may also send a (re)activation message to the relay node, which may indicate that the sidelink is (re)activated; whether the sidelink is (re)activated for only UL traffic, only DL traffic, or both UL and DL traffic; an ID for the remote UE node; and/or a traffic split ration between the direct llu connection and the sidelink.

While the processes described above for establishing and releasing (i.e. removing) links rely on RRC signalling to provide adequate transmission space for configuration parameters for the connections, activating or deactivating links does not require transmitting as much data, as modifications to existing configurations may be identified in the signalling. For example, and activation/deactivation message may only require a comparatively small number of bits as the message may refer to a particular link ID and include an activation/deactivation bit indicating that a link with that ID should be activated or deactivated. As such, MAC/PHY signalling (such a MAC Control Element (MAC CE) or Downlink Control Information (DCI)) may be used instead of RRC signalling to provide for faster and more efficient activation/deactivation of connections. However, RRC signalling may still be used for activation/deactivation of connection, for example to provide additional security. This activation/deactivation process may be performed after the specific processes discussed in relation to Figures 5-10, or may in some cases be performed independently from any of the processes shown in Figures 5-10.

The activation/deactivation of links may be performed dynamically, e.g. in response to shortterm changes in traffic demands (e.g. reported from a remote UE or relay node, or measured by a gNB). As such, the use of MAC/PHY signalling is particularly beneficial as it allows established links to be quickly activated/deactivated to meet this changing demand in order to avoid overutilization or underutilisation of network resources.

While Figures 7 and 8 above illustrate processes for releasing existing links in a multipath arrangement, in some cases a handover may occur, such that a particular sidelink or Uu link is replaced with a new sidelink or Uu link. An example is shown in Figure 9, where a Uu connection between a remote UE 910 and a source cell 920 of a gNB is handed over to a target cell 925 of the gNB. An indirect connection between the remote UE 910 and the gNB for both the source and target cells exists via a relay node 930 using a sidelink connection. The remote UE 910, gNB and relay node 930 may be substantially similar to the remote UEs, gNBs and relay nodes discussed above in relation to the other figures. In the present example, the gNB includes multiple cells 920, 925, each provided by a different RAN nodes.

At step 941 , data is exchanged between the remote UE 910 and the source cell, e.g. via the existing Uu 440 link and sidelink 450. In steps 942 and 943, a measurement procedure is performed in a similar manner to that described above in relation to Figure 5. For example, the source cell 920 may request 942 measurement data 943 from the remote UE relating to the remote UE’s 910 signal strength for the Uu connection 440. In other words, the source cell 920 may request 942 that the remote UE 910 measure its signal strength (e.g. via an RSRP or RSSI measurement) with the source cell 920. The remote UE 910 then reports this measurement data 943 to the source cell 920. The measurement request 942 and measurement data 943 may be transmitted via the direct Uu 440 link or the sidelink 450. Moreover, the remote UE 910 may in some cases perform the measurement and transmit the measurement data 943 without instruction from the source cell 920. The measurement data 943 may also indicate the remote UE’s 910 signal strength with a target cell 925 of the gNB.

Based on the measurement data 943, the source cell 920 (or gNB) determines 944 that the Uu connection 440 (which may be a MN for the remote UE 910) should be handed over to a new, target cell 925 of the gNB. That is, the source cell 920 (or gNB) may determine that the remote UE’s 910 signal strength with the source cell 920 is below a particular threshold and/or that the UE’s 910 signal strength with the target cell 925 is above a particular threshold, and therefore determines 944 that handover should be performed. The source cell 920 therefore transmits a handover request (HO) to the target cell 925, which performs admission control 946 for the remote UE 910, and transmits a HO acknowledgement (ACK) 947 to the source cell 920.

Based on receiving the HO ACK from the target cell 925, the source cell 920 transmits an RRC reconfiguration message 948 to the remote UE 910. The RRC reconfiguration message 948 directs the remote UE 910 to release (i.e. delete) the Uu connection to the source cell 920 (in a similar manner to that described above in relation to Figure 8) and initiate a RACH procedure 949 with the target cell 925 to establish a new Uu connection to the target cell 925. The remote UE 910 and target cell 925 then execute the RACH procedure 949 to establish the new Uu connection, in the same way as discussed above in relation to Figure 6. The target cell 925 may optionally transmit one or more messages 950 to the remote UE 910 and/or relay node 930 to modify one or more configuration parameters of the sidelink between the remote UE 910 and the relay node 930, however any such modifications may alternatively or additionally be transmitted in the RRC reconfiguration message 948 transmitted by the source cell 920. After the remote UE 910 has completed the reconfiguration, the UE 910 may transmit an RRC reconfiguration complete message to the target cell 925 to confirm that the UE 910 has configured the new Uu connection to the target cell 925. As such, a remote UE 910 with a direct Uu connection and an indirect connection to a gNB via a sidelink may be handed over between different cells of the gNB.

Figure 10 illustrates handover of a sidelink for a remote UE 1010 from a source relay node 1030 to a target relay node 1035, where an existing Uu connection exists between the remote UE 1010 and a gNB 1020, and the gNB 1020 has Uu connections to both the source relay node 1030 and target relay node 1035. Initially, data may be exchanged by the remote UE 1010 and the gNB 1020 via one or both of the Uu link 440 and indirect connection via the sidelink 450 and Uu link 445 between the source relay node 1030 and the gNB 1020.

In steps 1042 and 1043, a measurement procedure is performed in a similar manner to that described above in relation to Figure 5 and Figure 9. For example, the gNB 1020 may request 1042 measurement data 1043 from the remote UE 1010 relating to the remote UE’s 1010 signal strength for the sidelink. In other words, the gNB 1020 may request 942 that the remote UE 1010 measure its signal strength (e.g. via an RSRP or RSSI measurement) with the source relay node 1030. The remote UE 1010 then reports this measurement data 943 to the gNB 1020. The measurement request 1042 and measurement data 1043 may be transmitted via the direct Uu link or the sidelink/indirect connection. Moreover, the remote UE 1010 may in some cases perform the measurement and transmit the measurement data 1043 without instruction from the gNB 1020. The measurement data 1043 may also indicate the remote UE’s 1010 signal strength with a target relay node 1035 having a Uu connection with the gNB 1020.

Based on the measurement data 1043, the gNB 1020 may determine that the sidelink for the remote UE 1010 should be handed over from the source relay node 1030 to the target relay node 1035. That is, the gNB 1020 may determine that the remote UE’s 1010 signal strength with the source relay node 1030 is below a particular threshold and/or that the UE’s 1010 signal strength with the target relay node 1035 is above a particular threshold, and therefore determines 1044 that handover of the sidelink should be performed.

The gNB 1020 therefore transmits a first RRC reconfiguration message 1045 to the remote UE 1030 indicating that the remote UE 1010 should release (i.e. delete) its sidelink to the source relay node 1030 and establish a new sidelink to the target relay node 1035. The first RRC reconfiguration message 1045 may indicate any details that may be included in the RRC configuration messages 744 and 545 of Figures 7 and 5 respectively. For example, the first RRC reconfiguration message 1045 may include details of the sidelink to be released, such as an identifier for the source relay node 1030 and/or the sidelink, and modifications to (or deletion of) multipath configuration information, as well as the configuration information for the indirect connection, including e.g. sidelink configurations for establishing the new sidelink between the remote UE 1010 and the target relay node 1030, and an identifier for the target relay node 1030.

The gNB also transmits a second RRC reconfiguration message 1046 to the source relay node 1030 directing (i.e. instructing or indicating) the source relay node 1030 to release the sidelink to the remote UE 1010. The second RRC reconfiguration message 1046 may be substantially similar to the RRC reconfiguration message 743 of Figure 7, and as such may include any information that may be included in the RRC reconfiguration message 743 of Figure 7. For example, the second RRC reconfiguration message 1046 may indicate details of the sidelink to be released, such as an identifier for the remote UE 710 and/or the sidelink, and modifications to (or deletion of) multipath configuration information. In addition, the gNB transmits a third RRC reconfiguration message 1047 to the target relay node 1035 to establish the new sidelink to the remote 1010. The third RRC reconfiguration message 1047 may be substantially similar to the RRC reconfiguration message 544 of Figure 5, and as such may include any information that may be included within RRC reconfiguration message 544 of Figure 5. For example, the third RRC reconfiguration message 1047may include configuration information for the sidelink connection, including e.g. sidelink configurations for establishing the sidelink450 between the remote UE 510 and the relay node 530, and an identifier of the remote UE 510.

After receiving the RRC reconfiguration messages 1045, 1046, 1047, the remote UE 1010 and the source relay node 1030 release the sidelink between them, and the remote UE 1010 and the target relay node 1030 establish a new sidelink. The remote UE 1010 and/or target relay node 1035 may then transmit an RRC reconfiguration complete message 1050 confirming that the existing sidelink was released and that the new sidelink has been established for the indirect connection. As such, it is possible for a stable sidelink connection to be maintained for a roaming remote UE or relay node.

While the examples of Figures 5-10 have been described separately, it should be appreciated that the techniques of these examples may be combined with one another in substantially any manner. Moreover, it should be understood that the processes described herein for managing arrangements having both a direct and indirect connection between a remote UE and a gNB may be performed independently from any of the methods discussed in relation to Figures 5- 10.

Thus, from one perspective, there has now been described methods, communications devices, relay node, and infrastructure equipment for establishing and managing a multipath connection between a communications device and an infrastructure equipment. The multipath connection includes a direct radio connection between the communications device and an infrastructure equipment, and an indirect connection including a sidelink connection between the communications device and a relay node, where the relay node has a connection to the infrastructure equipment. Direct radio connections and sidelink connection can be established, released and handed over using RRC signaling, while MAC/PHY or RRC signaling may be used for management of the multipath connection. Further examples of feature combinations taught by the present disclosure are set out in the following numbered clauses:

1. A method of operating an infrastructure equipment configured to transmit signals to and/or to receive signals from a communications device and a relay node of a wireless communications network via a wireless radio interface provided by the wireless communications network, the method comprising: transmitting, to a communications device with which the infrastructure equipment has an existing direct radio connection, a first radio resource control (RRC) reconfiguration message including one or more first configuration parameters for a new sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; transmitting, to the relay node, a second RRC reconfiguration message including one or more second configuration parameters for the new sidelink connection between the communications device and the relay node; and receiving an RRC reconfiguration complete message indicating that the new sidelink connection between the communications device and the relay node has been established for the indirect connection.

2. The method according to clause 1 , wherein the first RRC reconfiguration message additionally directs the communications device to release an existing sidelink connection with another relay node used for the indirect connection between the communications device and the infrastructure equipment; and wherein the method further comprises transmitting to the other relay node, a third RRC reconfiguration message directing the other relay node to release the existing sidelink connection between the communications device and the other relay node.

3. A method of operating an infrastructure equipment configured to transmit signals to and/or to receive signals from a communications device and a relay node of a wireless communications network via a wireless radio interface provided by the wireless communications network, the method comprising: transmitting, to a communications device using an indirect connection between the communications device and the infrastructure equipment via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and executing a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment according to the configuration parameters.

4. The method according to clause 3, wherein the infrastructure equipment has an existing direct radio connection to the communications device, wherein the existing direct radio connection is a primary cell connection for the communications device, and wherein the new direct radio connection is a secondary cell connection for the communications device.

5. A method of operating an infrastructure equipment configured to transmit signals to and/or to receive signals from a communications device and a relay node of a wireless communications network via a wireless radio interface provided by the wireless communications network, the method comprising: transmitting, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a first RRC reconfiguration message directing the communications device to release the sidelink connection between the communications device and the relay node; transmitting, to the relay node, a second RRC reconfiguration message directing the relay node to release the sidelink connection between the communications device and the relay node; and receiving an RRC reconfiguration complete message indicating that the connection between the communications device and the relay node has been released.

6. A method of operating an infrastructure equipment configured to transmit signals to and/or to receive signals from a communications device and a relay node of a wireless communications network via a wireless radio interface provided by the wireless communications network, the method comprising: transmitting, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; receiving an RRC reconfiguration complete message indicating that the connection between the communications device and the infrastructure equipment has been released.

7. The method of clause 6, wherein the infrastructure equipment provides a first cell for a base station, and wherein the method further comprises: transmitting a handover request to another infrastructure equipment of the wireless communications network, the other infrastructure equipment providing a second cell for the base station; and receiving a handover request acknowledgement from the other infrastructure equipment; wherein the RRC reconfiguration message is transmitted based on receiving the handover request acknowledgement and includes configuration parameters for establishing a new direct radio connection between the communications device and the other infrastructure equipment.

8. A method of operating an infrastructure equipment configured to transmit signals to and/or to receive signals from a communications device and a relay node of a wireless communications network via a wireless radio interface provided by the wireless communications network, wherein the infrastructure equipment provides a first cell for a base station, wherein the method comprises: receiving a handover request from another infrastructure equipment of the wireless communications network for a communications device, the other infrastructure equipment providing a second cell for the base station, and the other infrastructure equipment having an existing direct radio connection with the communications device and an existing indirect connection with the communications device via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node; and transmitting a handover request acknowledgement to the other infrastructure equipment; based on transmitting the handover request acknowledgement, executing a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment.

9. The method according to clause 8, further comprising: transmitting and/or receiving one or more signals to and/or from the communications device for modifying one or more configuration parameters for the connection between the communications device and the relay node.

10. The method according to any preceding clause, wherein the direct radio connection between the communications device and the infrastructure equipment is a llu connection, and wherein the sidelink connection between the communications device and the relay node is a PC5 connection, WiFi connection, or Bluetooth connection.

11 . The method according to any preceding clause, wherein the infrastructure equipment maintains a single medium access control (MAC) entity for both the RRC and indirect connections to the communications device.

12. The method according to any preceding clause, wherein the sidelink connection is a secondary cell connection for the communications device, and wherein the direct radio connection is a primary cell connection for the communications device.

13. The method of any preceding clause, further comprising: transmitting, to the communications device, an RRC reconfiguration message including one or more third configuration parameters for another sidelink connection between the communications device and another relay node for another indirect connection between the communications device and the infrastructure equipment; transmitting, to the other relay node, an RRC reconfiguration message including one or more fourth configuration parameters for the other sidelink connection between the communications device and the other relay node; and receiving another RRC reconfiguration complete message indicating that the other connection between the communications device and the other relay node has been established for the indirect connection.

14. The method according to any preceding clause, further comprising: transmitting, to the communications device and/or relay node, a deactivation message directing the communications device and/or relay node to deactivate the sidelink connection; and/or transmitting, to the communications device and/or relay node, a reactivation message directing the communications device and/or relay node to reactivate the sidelink connection.

15. The method according to clause 14, wherein the deactivation message and/or reactivation message are transmitted using one of MAC signalling, physical layer signalling, or RRC signalling.

16. The method according to clause 14 or clause 15, wherein the deactivation or reactivation of the sidelink connection is based on a determined traffic demand for the communications device and/or relay node. 17. The method according to clause 16, wherein the determined traffic demand for the communications device is based on a measured traffic demand for the communications device and/or relay node, and/or a reported traffic demand from the communications device and/or relay node.

18. The method according to any of clauses 14-17, wherein the deactivation message and/or reactivation message includes an identifier for the communications device and/or relay node.

19. The method according to any of clauses 14-18, wherein the deactivation message and/or reactivation message reactivates/deactivates the sidelink: only for uplink traffic, only for downlink traffic, or for both uplink and downlink traffic.

20. The method according to any of clauses 14-19, wherein the reactivation message includes an indication of a traffic split ratio between the direct radio connection and the sidelink connection.

21 . The method according to any preceding clause, further comprising: transmitting, to the communications device, an indication of a traffic split ratio between the direct radio connection and the sidelink connection.

22. An infrastructure equipment comprising: a transceiver configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and a controller configured in combination with the transceiver to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection, a first radio resource control (RRC) reconfiguration message including one or more first configuration parameters for a new sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; transmit, to the relay node, a second RRC reconfiguration message including one or more second configuration parameters for the new sidelink connection between the communications device and the relay node; and receive an RRC reconfiguration complete message indicating that the new sidelink connection between the communications device and the relay node has been established for the indirect connection.

23. An infrastructure equipment comprising: a transceiver configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and a controller configured in combination with the transceiver to: transmit, to a communications device using an indirect connection between the communications device and the infrastructure equipment via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and execute a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment according to the configuration parameters.

24. An infrastructure equipment comprising: a transceiver configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and a controller configured in combination with the transceiver to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a first RRC reconfiguration message directing the communications device to release the sidelink connection between the communications device and the relay node; transmit, to the relay node, a second RRC reconfiguration message directing the relay node to release the sidelink connection between the communications device and the relay node; and receive an RRC reconfiguration complete message indicating that the connection between the communications device and the relay node has been released.

25. An infrastructure equipment comprising: a transceiver configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and a controller configured in combination with the transceiver to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; receive an RRC reconfiguration complete message indicating that the connection between the communications device and the infrastructure equipment has been released.

26. An infrastructure equipment comprising: a transceiver configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and a controller configured in combination with the transceiver to: receive a handover request from another infrastructure equipment of the wireless communications network for a communications device, the other infrastructure equipment providing a second cell for the base station, and the other infrastructure equipment having an existing direct radio connection with the communications device and an existing indirect connection with the communications device via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node; and transmit a handover request acknowledgement to the other infrastructure equipment; based on transmitting the handover request acknowledgement, execute a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment.

27. Circuitry for an infrastructure equipment comprising: transceiver circuitry configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection, a first radio resource control (RRC) reconfiguration message including one or more first configuration parameters for a new sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; transmit, to the relay node, a second RRC reconfiguration message including one or more second configuration parameters for the new sidelink connection between the communications device and the relay node; and receive an RRC reconfiguration complete message indicating that the new sidelink connection between the communications device and the relay node has been established for the indirect connection.

28. Circuitry for an infrastructure equipment comprising: transceiver circuitry configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to: transmit, to a communications device using an indirect connection between the communications device and the infrastructure equipment via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and execute a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment according to the configuration parameters.

29. Circuitry for an infrastructure equipment comprising: transceiver circuitry configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a first RRC reconfiguration message directing the communications device to release the sidelink connection between the communications device and the relay node; transmit, to the relay node, a second RRC reconfiguration message directing the relay node to release the sidelink connection between the communications device and the relay node; and receive an RRC reconfiguration complete message indicating that the connection between the communications device and the relay node has been released.

30. Circuitry for an infrastructure equipment comprising: transceiver circuitry configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to: transmit, to a communications device with which the infrastructure equipment has an existing direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; receive an RRC reconfiguration complete message indicating that the connection between the communications device and the infrastructure equipment has been released.

31 . Circuitry for an infrastructure equipment comprising: transceiver circuitry configured to transmit signals to and/or receive signals from a communications device and a relay node via a wireless radio interface provided by the wireless communications network, and controller circuitry configured in combination with the transceiver circuitry to: receive a handover request from another infrastructure equipment of the wireless communications network for a communications device, the other infrastructure equipment providing a second cell for the base station, and the other infrastructure equipment having an existing direct radio connection with the communications device and an existing indirect connection with the communications device via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node; and transmit a handover request acknowledgement to the other infrastructure equipment; based on transmitting the handover request acknowledgement, execute a random access channel (RACH) procedure with the communications device to establish the new direct radio connection between the communications device and the infrastructure equipment.

32. A method of operating a communications device configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, the method comprising: receiving, from an infrastructure equipment having an existing direct radio connection with the communications device, an RRC reconfiguration message, the RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; establishing the sidelink connection with the relay node.

33. A method of operating a communications device configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, the method comprising: receiving, via a relay node and from an infrastructure equipment having an existing indirect connection with the communications device via the relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and executing a random access channel (RACH) procedure with the infrastructure equipment to establish the new direct radio connection with the infrastructure equipment according to the configuration parameters.

34. A method of operating a communications device configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, the method comprising: receiving, from an infrastructure equipment with which the communications device has a direct radio connection and a indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the connection sidelink between the communications device and the relay node; and releasing the sidelink connection with the relay node.

35. The method according to clause 34, wherein the RRC reconfiguration message additionally includes configuration parameters for establishing another sidelink connection between the communications device and another relay node for another indirect connection between the communications device and the infrastructure equipment; and wherein the method further comprises establishing the other sidelink connection to the other relay node for the other indirect connection.

36. A method of operating a communications device configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, the method comprising: receiving, from an infrastructure equipment with which the communications device has a direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; and releasing the direct radio connection with the infrastructure equipment.

37. The method according to clause 36, wherein the RRC reconfiguration message is received from a first cell of the infrastructure equipment, and wherein the RRC reconfiguration message additionally includes configuration parameters for establishing an direct radio connection between the communications device and a second cell of the infrastructure equipment; and wherein the method further comprises executing a random access channel (RACH) procedure with the infrastructure equipment to establish the direct radio connection between the communications device and the second cell of the infrastructure equipment according to the configuration parameters.

38. The method according to any of clauses 32-37, further comprising: identifying a first traffic split ratio between the direct radio connection and the sidelink connection; and determining that the first traffic split ratio should be modified; and transmitting network traffic at a second traffic split ratio different to the first traffic split ratio.

39. The method according to clause 38, wherein an indication of the first traffic split ratio is received from the infrastructure equipment.

40. The method according to any of clauses 37-39, further comprising: transmitting a buffer status report for the sidelink connection to relay node.

41 . A communications device, the communications device comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and a controller configured in combination with the one or more transceivers to: receive, from an infrastructure equipment having an existing direct radio connection with the communications device, an RRC reconfiguration message, the RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; establish the sidelink connection with the relay node.

42. A communications device, the communications device comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and a controller configured in combination with the one or more transceivers to: receive, via a relay node and from an infrastructure equipment having an existing indirect connection with the communications device via the relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and execute a random access channel (RACH) procedure with the infrastructure equipment to establish the new direct radio connection with the infrastructure equipment according to the configuration parameters.

43. A communications device, the communications device comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and a controller configured in combination with the one or more transceivers to: receive, from an infrastructure equipment with which the communications device has a direct radio connection and a indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the connection sidelink between the communications device and the relay node; and release the sidelink connection with the relay node.

44. A communications device, the communications device comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and a controller configured in combination with the one or more transceivers to: receive, from an infrastructure equipment with which the communications device has a direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; and release the direct radio connection with the infrastructure equipment.

45. Circuitry for a communications device comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, from an infrastructure equipment having an existing direct radio connection with the communications device, an RRC reconfiguration message, the RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and a relay node, the new sidelink connection forming part of an indirect connection between the communications device and the infrastructure equipment; establish the sidelink connection with the relay node.

46. Circuitry for a communications device comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, via a relay node and from an infrastructure equipment having an existing indirect connection with the communications device via the relay node, the indirect connection including a sidelink connection between the communications device and the relay node, a radio resource control (RRC) reconfiguration message, the RRC reconfiguration message including configuration parameters for establishing a new direct radio connection between the communications device and the infrastructure equipment; and execute a random access channel (RACH) procedure with the infrastructure equipment to establish the new direct radio connection with the infrastructure equipment according to the configuration parameters.

47. Circuitry for a communications device comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, from an infrastructure equipment with which the communications device has a direct radio connection and a indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the connection sidelink between the communications device and the relay node; and release the sidelink connection with the relay node.

48. Circuitry for a communications device comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a relay device of the wireless communications network, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, from an infrastructure equipment with which the communications device has a direct radio connection and an indirect connection via a relay node, the indirect connection including a sidelink connection between the communications device and the relay node, an RRC reconfiguration message directing the communications device to release the direct radio connection between the communications device and the infrastructure equipment; and release the direct radio connection with the infrastructure equipment.

49. A method of operating a relay node configured transmit signals to and/or receive signals from a communications device and an infrastructure equipment of a wireless communications network for a sidelink connection between the communications device and the infrastructure equipment, the method comprising: receiving, from an infrastructure equipment having an existing direct radio connection with a communications device, an RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and the infrastructure equipment via the relay node; and establishing a connection with the communications device for the sidelink connection.

50. A method of operating a relay node configured transmit signals to and/or receive signals from a communications device and an infrastructure equipment of a wireless communications network for a sidelink connection between the communications device and the infrastructure equipment, the method comprising: receiving, from an infrastructure equipment having an existing direct radio connection with a communications device and an existing sidelink connection with the communications device via the relay node, an RRC reconfiguration message directing the directing the communications device to release a connection between the communications device and the relay node forming part of the sidelink connection; and releasing the connection with the communications device.

51. The method according to clause 49 or clause 50, further comprising: determining a first buffer status report for reporting to the infrastructure equipment; receiving, from the communications device, a second buffer status report for the sidelink connection; based on the second buffer status report received from the communications device, modifying the first buffer status report to the infrastructure equipment, wherein modifying the first buffer status report includes increased an expected quantity of data to be transmitted using the sidelink connection; transmitting the modified first buffer status report to the infrastructure equipment.

52. A relay node comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a communications device, and a controller configured in combination with the one or more transceivers to: receive, from an infrastructure equipment having an existing direct radio connection with a communications device, an RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and the infrastructure equipment via the relay node; and establish a connection with the communications device for the sidelink connection.

53. A relay node comprising: one or more transceivers configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a communications device, and a controller configured in combination with the one or more transceivers to: receive, from an infrastructure equipment having an existing direct radio connection with a communications device and an existing sidelink connection with the communications device via the relay node, an RRC reconfiguration message directing the directing the communications device to release a connection between the communications device and the relay node forming part of the sidelink connection; and release the connection with the communications device.

54. Circuitry for a relay node comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, from an infrastructure equipment having an existing direct radio connection with a communications device, an RRC reconfiguration message including one or more configuration parameters for a sidelink connection between the communications device and the infrastructure equipment via the relay node; and establish a connection with the communications device for the sidelink connection.

55. Circuitry for a relay node comprising: one or more transceiver circuitries configured to transmit signals to and/or to receive signals from an infrastructure equipment of a wireless communications network via a wireless radio interface provided by the wireless communications network, and to transmit signals to and/or to receive signals from a communications device, and controller circuitry configured in combination with the one or more transceiver circuitries to: receive, from an infrastructure equipment having an existing direct radio connection with a communications device and an existing sidelink connection with the communications device via the relay node, an RRC reconfiguration message directing the directing the communications device to release a connection between the communications device and the relay node forming part of the sidelink connection; and release the connection with the communications device.

REFERENCES

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

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

Claims

2. The method according to claim 1 , wherein the first RRC reconfiguration message additionally directs the communications device to release an existing sidelink connection with another relay node used for the indirect connection between the communications device and the infrastructure equipment; and wherein the method further comprises transmitting to the other relay node, a third RRC reconfiguration message directing the other relay node to release the existing sidelink connection between the communications device and the other relay node.

4. The method according to claim 3, wherein the infrastructure equipment has an existing direct radio connection to the communications device, wherein the existing direct radio connection is a primary cell connection for the communications device, and wherein the new direct radio connection is a secondary cell connection for the communications device.

7. The method of claim 6, wherein the infrastructure equipment provides a first cell for a base station, and wherein the method further comprises: transmitting a handover request to another infrastructure equipment of the wireless communications network, the other infrastructure equipment providing a second cell for the base station; and receiving a handover request acknowledgement from the other infrastructure equipment; wherein the RRC reconfiguration message is transmitted based on receiving the handover request acknowledgement and includes configuration parameters for establishing a new direct radio connection between the communications device and the other infrastructure equipment.

9. The method according to claim 8, further comprising: transmitting and/or receiving one or more signals to and/or from the communications device for modifying one or more configuration parameters for the connection between the communications device and the relay node.

10. The method according to claim 1 , wherein the direct radio connection between the communications device and the infrastructure equipment is a llu connection, and wherein the sidelink connection between the communications device and the relay node is a PC5 connection, WiFi connection, or Bluetooth connection.

11. The method according to claim 1 , wherein the infrastructure equipment maintains a single medium access control (MAC) entity for both the RRC and indirect connections to the communications device.

12. The method according to claim 1 , wherein the sidelink connection is a secondary cell connection for the communications device, and wherein the direct radio connection is a primary cell connection for the communications device.

13. The method of claim 1 , further comprising: transmitting, to the communications device, an RRC reconfiguration message including one or more third configuration parameters for another sidelink connection between the communications device and another relay node for another indirect connection between the communications device and the infrastructure equipment; transmitting, to the other relay node, an RRC reconfiguration message including one or more fourth configuration parameters for the other sidelink connection between the communications device and the other relay node; and receiving another RRC reconfiguration complete message indicating that the other connection between the communications device and the other relay node has been established for the indirect connection.

14. The method according to claim 1 , further comprising: transmitting, to the communications device and/or relay node, a deactivation message directing the communications device and/or relay node to deactivate the sidelink connection; and/or transmitting, to the communications device and/or relay node, a reactivation message directing the communications device and/or relay node to reactivate the sidelink connection.

15. The method according to claim 14, wherein the deactivation message and/or reactivation message are transmitted using one of MAC signalling, physical layer signalling, or RRC signalling.

16. The method according to claim 14, wherein the deactivation or reactivation of the sidelink connection is based on a determined traffic demand for the communications device and/or relay node.

17. The method according to claim 16, wherein the determined traffic demand for the communications device is based on a measured traffic demand for the communications device and/or relay node, and/or a reported traffic demand from the communications device and/or relay node.

18. The method according to claim 14, wherein the deactivation message and/or reactivation message includes an identifier for the communications device and/or relay node.

19. The method according to claim 14, wherein the deactivation message and/or reactivation message reactivates/deactivates the sidelink: only for uplink traffic, only for downlink traffic, or for both uplink and downlink traffic.

20. The method according to claim 14, wherein the reactivation message includes an indication of a traffic split ratio between the direct radio connection and the sidelink connection.

21 . The method according to claim 1 , further comprising: transmitting, to the communications device, an indication of a traffic split ratio between the direct radio connection and the sidelink connection.

35. The method according to claim 34, wherein the RRC reconfiguration message additionally includes configuration parameters for establishing another sidelink connection between the communications device and another relay node for another indirect connection between the communications device and the infrastructure equipment; and wherein the method further comprises establishing the other sidelink connection to the other relay node for the other indirect connection.

37. The method according to claim 36, wherein the RRC reconfiguration message is received from a first cell of the infrastructure equipment, and wherein the RRC reconfiguration message additionally includes configuration parameters for establishing an direct radio connection between the communications device and a second cell of the infrastructure equipment; and wherein the method further comprises executing a random access channel (RACH) procedure with the infrastructure equipment to establish the direct radio connection between the communications device and the second cell of the infrastructure equipment according to the configuration parameters.

38. The method according to claim 32, further comprising: identifying a first traffic split ratio between the direct radio connection and the sidelink connection; and determining that the first traffic split ratio should be modified; and transmitting network traffic at a second traffic split ratio different to the first traffic split ratio.

39. The method according to claim 38, wherein an indication of the first traffic split ratio is received from the infrastructure equipment.

40. The method according to claims 37, further comprising: transmitting a buffer status report for the sidelink connection to relay node.

51. The method according to claim 49, further comprising: determining a first buffer status report for reporting to the infrastructure equipment; receiving, from the communications device, a second buffer status report for the sidelink connection; based on the second buffer status report received from the communications device, modifying the first buffer status report to the infrastructure equipment, wherein modifying the first buffer status report includes increased an expected quantity of data to be transmitted using the sidelink connection; transmitting the modified first buffer status report to the infrastructure equipment.