WO2025045333A1

WO2025045333A1 - Method, apparatus and computer program

Info

Publication number: WO2025045333A1
Application number: PCT/EP2023/073387
Authority: WO
Inventors: Timo Koskela; Juha Pekka Karjalainen; Sami-Jukka Hakola
Original assignee: Nokia Technologies Oy
Current assignee: Nokia Technologies Oy
Priority date: 2023-08-25
Filing date: 2023-08-25
Publication date: 2025-03-06
Anticipated expiration: 2026-02-25

Abstract

There is provided a user equipment comprising means for: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

Description

METHOD, APPARATUS AND COMPUTER PROGRAM

FIELD

The present application relates to a method, apparatus, system and computer program and in particular but not exclusively to reporting uplink beam information.

BACKGROUND

A communication system can be seen as a facility that enables communication sessions between two or more entities such as user terminals, base stations and/or other nodes by providing carriers between the various entities involved in the communications path. A communication system can be provided for example by means of a communication network and one or more compatible communication devices. The communication sessions may comprise, for example, communication of data for carrying communications such as voice, video, electronic mail (email), text message, multimedia and/or content data and so on. Nonlimiting examples of services provided comprise two-way or multi-way calls, data communication or multimedia services and access to a data network system, such as the Internet.

In a wireless communication system at least a part of a communication session between at least two stations occurs over a wireless link. Examples of wireless systems comprise public land mobile networks (PLMN), satellite based communication systems and different wireless local networks, for example wireless local area networks (WLAN). Some wireless systems can be divided into cells, and are therefore often referred to as cellular systems.

A user can access the communication system by means of an appropriate communication device or terminal. A communication device of a user may be referred to as user equipment (UE) or user device. A communication device is provided with an appropriate signal receiving and transmitting apparatus for enabling communications, for example enabling access to a communication network or communications directly with other users. The communication device may access a carrier provided by a station, for example a base station of a cell, and transmit and/or receive communications on the carrier.

The communication system and associated devices typically operate in accordance with a given standard or specification which sets out what the various entities associated with the system are permitted to do and how that should be achieved. Communication protocols and/or parameters which shall be used for the connection are also typically defined. One example of a communications system is UTRAN (3G radio). Other examples of communication systems are the long-term evolution (LTE) of the Universal Mobile Telecommunications System (UMTS) radio-access technology and so-called 5G or New Radio (NR) networks. NR is being standardized by the 3rd Generation Partnership Project (3GPP). Yet another example of a communications system is a so-called 6G system.

SUMMARY

According to an aspect, there is provided a user equipment comprising means for: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

Determining that the trigger condition has been satisfied may comprise determining that the user equipment has obtained a path loss estimate for one of: at least one downlink reference signal resource associated with the one or more uplink transmissions; or at least one pair of downlink reference signal resources associated with the one or more uplink transmissions, wherein the user equipment is configured for simultaneous uplink transmission.

The information related to one or more uplink transmissions may comprise: an indicator of the at least one downlink reference signal resource or the at least one pair of downlink reference signal resources for which the user equipment has obtained a path loss measurement; or information indicating that the at least one downlink reference signal resource or the at least one pair of downlink reference signal resources is maintained for path loss estimation.

The information indicating that the at least one downlink reference signal resource or the pair of downlink reference signal resources is maintained for path loss estimation may comprise information indicating a duration for which the path loss estimation is maintained.

The duration may be configured based on information received from a network entity. The information related to the one or more uplink transmissions may comprise an indication that two or more of the at least one downlink reference signal resources are associated with each other for simultaneous uplink transmission.

The information related to the one or more uplink transmissions may comprise information indicating that a reported pair of downlink reference signal resources associated with different downlink reference signal resource sets are maintained for path loss estimation.

The user equipment may be configured to operate in at least one of the following modes of operation: a first mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference signal resources, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference signal resource in the set; a second mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a third mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fourth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are not activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fifth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured as transmitted synchronization signal blocks, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set.

The means may be further for: receiving an indication from the access node indicating one of the modes of operation and activating the mode of operation based on the received indication.

The means may be further for: determining that the user equipment is configured with a unified transmission configuration indicator state or at least one unified transmission configuration indicator state is activated, wherein sending the uplink beam information reporting message may be further based on the determining that the user equipment is configured with the unified transmission configuration indicator state or the at least one unified transmission configuration indicator state is activated.

The information related to the one or more uplink transmission may comprise at least one of: an indication that a reported downlink reference signal resource is monitored for path loss estimation and/or that a path loss estimate has been obtained; an identifier reporting configuration that indicates that a reported downlink reference signal resource is monitored for path loss estimation or that a path loss estimation has been obtained; or a medium access control control element comprising information indicating the downlink reference signal resources that are monitored for path loss estimation or for which a path loss estimate has been obtained.

The means may be further for: receiving, from the access node, information indicating at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources.

The at least one downlink reference signal may comprise a synchronization signal block and/or channel state information reference signal.

The one or more downlink reference signals may be associated with one or more transmission configuration indicator states for uplink transmission

According to an aspect there is provided an access node comprising means for: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

The access node may further comprise means for: sending, to the user equipment, an indication of one of the modes of operation for performing uplink beam information reporting.

The access node may further comprise means for: based on the uplink beam information reporting message, performing uplink beam switching for the user equipment to determine at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources; and sending, to the user equipment, information indicating the determined at least one new uplink beam. According to an aspect, there is provided a user equipment comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the user equipment at least to: perform path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determine that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, send, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

The at least one processor may be configured to cause the user equipment to determine that the user equipment has obtained a path loss estimate for one of: at least one downlink reference signal resource associated with the one or more uplink transmissions; or at least one pair of downlink reference signal resources associated with the one or more uplink transmissions, wherein the user equipment is configured for simultaneous uplink transmission.

The duration may be configured based on information received from a network entity.

The information related to the one or more uplink transmissions may comprise an indication that two or more of the at least one downlink reference signal resources are associated with each other for simultaneous uplink transmission.

The information related to the one or more uplink transmissions may comprise information indicating that a reported pair of downlink reference signal resources associated with different downlink reference signal resource sets are maintained for path loss estimation. The user equipment may be configured to operate in at least one of the following modes of operation: a first mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference signal resources, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference signal resource in the set; a second mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a third mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fourth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are not activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fifth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured as transmitted synchronization signal blocks, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set.

The at least one processor may be configured to cause the user equipment to: receive an indication from the access node indicating one of the modes of operation and activate the mode of operation based on the received indication.

The at least one processor may be configured to cause the user equipment to: determine that the user equipment is configured with a unified transmission configuration indicator state or at least one unified transmission configuration indicator state is activated, wherein the at least one processor may be configured to cause the user equipment to send the uplink beam information reporting message further based on determining that the user equipment is configured with the unified transmission configuration indicator state or the at least one unified transmission configuration indicator state is activated.

The at least one processor may be configured to cause the user equipment to: receive, from the access node, information indicating at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources.

According to an aspect, there is provided an access node comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the access node at least to: receive, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

The at least one processor may be configured to cause the access node to: send, to the user equipment, an indication of one of the modes of operation for performing uplink beam information reporting.

The at least one processor may be configured to cause the access node to: based on the uplink beam information reporting message, perform uplink beam switching for the user equipment to determine at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources; and send, to the user equipment, information indicating the determined at least one new uplink beam.

According to an aspect, there is provided a method performed at a user equipment, the method comprising: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

The method may further comprise: receiving an indication from the access node indicating one of the modes of operation and activating the mode of operation based on the received indication.

The method may further comprise: determining that the user equipment is configured with a unified transmission configuration indicator state or at least one unified transmission configuration indicator state is activated, wherein sending the uplink beam information reporting message may be further based on the determining that the user equipment is configured with the unified transmission configuration indicator state or the at least one unified transmission configuration indicator state is activated.

The information related to the one or more uplink transmission may comprise at least one of: an indication that a reported downlink reference signal resource is monitored for path loss estimation and/or that a path loss estimate has been obtained; an identifier reporting configuration that indicates that a reported downlink reference signal resource is monitored for path loss estimation or that a path loss estimation has been obtained; or a medium access control control element comprising information indicating the downlink reference signal resources that are monitored for path loss estimation or for which a path loss estimate has been obtained. The method may further comprise: receiving, from the access node, information indicating at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources.

The one or more downlink reference signals may be associated with one or more transmission configuration indicator states for uplink transmission.

According to an aspect there is provided a method performed at an access node, the method comprising: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

The method may further comprise: sending, to the user equipment, an indication of one of the modes of operation for performing uplink beam information reporting.

The method may further comprise: based on the uplink beam information reporting message, performing uplink beam switching for the user equipment to determine at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources; and sending, to the user equipment, information indicating the determined at least one new uplink beam.

According to an aspect, there is provided a computer readable medium comprising instructions which, when executed by a user equipment, cause the user equipment to perform at least the following: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

The instructions, when executed by the user equipment, may further cause the user equipment to perform: receiving an indication from the access node indicating one of the modes of operation and activating the mode of operation based on the received indication.

The instructions, when executed by the user equipment, may further cause the user equipment to perform: determining that the user equipment is configured with a unified transmission configuration indicator state or at least one unified transmission configuration indicator state is activated, wherein sending the uplink beam information reporting message may be further based on the determining that the user equipment is configured with the unified transmission configuration indicator state or the at least one unified transmission configuration indicator state is activated.

The instructions, when executed by the user equipment, may further cause the user equipment to perform: receiving, from the access node, information indicating at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources.

The at least one downlink reference signal may comprise a synchronization signal block and/or channel state information reference signal. The one or more downlink reference signals may be associated with one or more transmission configuration indicator states for uplink transmission.

According to an aspect, there is provided a computer readable medium comprising instructions which, when executed by an access node, cause the access node to perform at least the following: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

The instructions, when executed by the access node, may further cause the access node to perform: sending, to the user equipment, an indication of one of the modes of operation for performing uplink beam information reporting.

The instructions, when executed by the access node, may further cause the access node to perform: based on the uplink beam information reporting message, performing uplink beam switching for the user equipment to determine at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources; and sending, to the user equipment, information indicating the determined at least one new uplink beam.

According to an aspect, there is provided a non-transitory computer readable medium comprising program instructions that, when executed by an apparatus, cause the apparatus to perform at least the method according to any of the preceding aspects.

In the above, many different embodiments have been described. It should be appreciated that further embodiments may be provided by the combination of any two or more of the embodiments described above.

DESCRIPTION OF FIGURES

Embodiments will now be described, by way of example only, with reference to the accompanying Figures in which:

Figure 1 shows a representation of a network system according to some example embodiments;

Figure 2 shows a representation of a control apparatus according to some example embodiments; Figure 3 shows a representation of an apparatus according to some example embodiments;

Figure 4 shows methods according to some examples.

DETAILED DESCRIPTION

In the following certain embodiments are explained with reference to mobile communication devices capable of communication via a wireless cellular system and mobile communication systems serving such mobile communication devices. Before explaining in detail the exemplifying embodiments, certain general principles of a wireless communication system, access systems thereof, and mobile communication devices are briefly explained with reference to Figures 1 , 2 and 3 to assist in understanding the technology underlying the described examples.

Figure 1 shows a schematic representation of a 5G system (5GS). The 5GS may be comprised by a terminal or user equipment (UE), a 5G radio access network (5GRAN) or next generation radio access network (NG-RAN), a 5G core network (5GC), one or more application function (AF) and one or more data networks (DN).

The 5G-RAN may comprise one or more gNodeB (GNB) or one or more gNodeB (GNB) distributed unit functions connected to one or more gNodeB (GNB) centralized unit functions. The 5GC may comprise the following entities: Network Slice Selection Function (NSSF); Network Exposure Function; Network Repository Function (NRF); Policy Control Function (PCF); Unified Data Management (UDM); Application Function (AF); Authentication Server Function (AUSF); an Access and Mobility Management Function (AMF); and Session Management Function (SMF). Figure 1 also shows the various interfaces (N1 , N2 etc.) that may be implemented between the various elements of the system.

Figure 2 illustrates an example of a control apparatus 200 for controlling a function of the 5GRAN or the 5GC as illustrated on Figure 1. The control apparatus may comprise at least one random access memory (RAM) 211 a, at least on read only memory (ROM) 211b, at least one processor 212, 213 and an input/output interface 214. The at least one processor 212, 213 may be coupled to the RAM 211a and the ROM 211 b. The at least one processor 212, 213 may be configured to execute an appropriate software code 215. The software code 215 may for example allow to perform one or more steps to perform one or more of the present aspects. The software code 215 may be stored in the ROM 211b. The control apparatus 200 may be interconnected with another control apparatus 200 controlling another function of the 5GRAN or the 5GC. In some embodiments, each function of the 5GRAN or the 5GC comprises a control apparatus 200. In alternative embodiments, two or more functions of the 5GRAN or the 5GC may share a control apparatus.

Figure 3 illustrates an example of a terminal 300, such as the terminal illustrated on Figure 1. The terminal 300 may be provided by any device capable of sending and receiving radio signals. Non-limiting examples comprise a user equipment, a mobile station (MS) or mobile device such as a mobile phone or what is known as a ’smart phone’, a computer provided with a wireless interface card or other wireless interface facility (e.g., USB dongle), a personal data assistant (PDA) or a tablet provided with wireless communication capabilities, a machine-type communications (MTC) device, an Internet of things (loT) type communication device or any combinations of these or the like. The terminal 300 may provide, for example, communication of data for carrying communications. The communications may be one or more of voice, electronic mail (email), text message, multimedia, data, machine data and so on.

The terminal 300 may receive signals over an air or radio interface 307 via appropriate apparatus for receiving and may transmit signals via appropriate apparatus for transmitting radio signals. In Figure 3 transceiver apparatus is designated schematically by block 306. The transceiver apparatus 306 may be provided for example by means of a radio part and associated antenna arrangement. The antenna arrangement may be arranged internally or externally to the mobile device.

The terminal 300 may be provided with at least one processor 301 , at least one memory ROM 302a, at least one RAM 302b and other possible components 303 for use in software and hardware aided execution of tasks it is designed to perform, including control of access to and communications with access systems and other communication devices. The at least one processor 301 is coupled to the RAM 302b and the ROM 302a. The at least one processor 301 may be configured to execute an appropriate software code 308. The software code 308 may for example allow to perform one or more of the present aspects. The software code 308 may be stored in the ROM 302a.

The processor, storage and other relevant control apparatus can be provided on an appropriate circuit board and/or in chipsets. This feature is denoted by reference 304. The device may optionally have a user interface such as key pad 305, touch sensitive screen or pad, combinations thereof or the like. Optionally one or more of a display, a speaker and a microphone may be provided depending on the type of the device. In some communication systems, such as 5G and 6G systems, communications between access node and user equipment may take place via one or more beams. As part of a beam management framework, beam reporting may be used to help the system align access node and UE side beams for both downlink and uplink. In some examples, beam reporting may comprise the UE measuring downlink reference signals that characterize different access node beams using a receive beam or different receive beams and providing measurement results (e.g. layer 1 -reference signal received power (L1-RSRP) measurements) to the network. The access node may use the measurements for downlink (DL) and uplink (UL) beam selection.

In some examples, the measurement results may be used for selecting UL and DL beams for beam management in a unified transmission configuration indicator (TCI) framework. The framework may support joint or separate DL/UL. In separate DL/UL the UE may be configured with TCI states separately for downlink and uplink. Thus separate beams may be used to communicate on uplink and downlink direction.

In some examples the UE may estimate and/or maintain pathloss information (e.g. for UL transmission for UL TCI state or for UL transmission for joint DL/UL TCI State) for a set of reference signals. The path loss estimate (and maintenance of the path loss estimate) for the set of reference signals may not be known to the network but may be known to the UE. In some examples the activated TCI state may be a joint TCI - for example when the UE monitors a DL reference signal (RS) for downlink synch and thus the UE may have path loss estimate corresponding to the RS indicated by the TCI state. In other examples, for some of the DL RS associated with TCI states the path loss estimation may not be maintained/estimated. In some examples the path loss estimation may be maintained for one or more DL RS associated with activated TCI States. In some examples, the path loss estimate may not be maintained for (all of the) DL RS associated with activated UL TCI states. In some examples, the path loss estimate may not be maintained for DL RS associated with TCI states that are not activated.

The path loss estimation for in any of the examples herein, may comprise of the UE performing a set of measurements on the DL RS for which the path loss is estimated. The number of measurements may be required to be performed within specific time window. The specific time window may be determined/calculated based on the reference signal periodicity. The specific time window may be determined/calculated based on additionally the assumption whether the UE RX beamforming is used. In some examples, the maintaining of path loss estimate may refer to UE having measured/estimated path loss and be continuously estimating (e.g. performing measurements) of the DL RS to maintain the estimate. In some cases it may be beneficial to enhance the beam reporting procedure to enable faster link switch or provide network additional information for scheduling. Some examples of the present disclosure may enhance beam management/reporting procedures by implementing UE event-based reporting. Some examples may relate to uplink beam switching considering single transmission and/or simultaneous UL transmission with respect to the path loss measurement.

Reference is made to Figure 4, which shows methods according to some examples.

At 400, a method comprises performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions.

At 402 the method comprises, based on the path loss measurements, determining that a trigger condition has been satisfied.

At 404 the method comprises, based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

In some examples steps 400-404 may be performed at or by a user equipment.

At 406, a method comprises receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

In some examples step 406 may be performed at or by an access node.

In some examples the UE may be configured with an event trigger that, when satisfied, triggers the UE to report UL beam information comprising information related to one or more UL TCI states. In some examples, the UE may report the UL beam information in a message (hereinafter referred to as a UL beam information reporting message). The event trigger may be associated with a set of one or more DL RS resources that are associated with the one or more UL TCI states or one or more joint DL/UL TCI states. The event trigger may for example be related to path loss measurement related information. As used herein, DL RS may refer to SSB and/or CSI-RS (including non-zero power (NZP)-CSI-RS), and/or positioning reference signal (PRS), tracking reference signals (TRS), or any other reference signal.

In any of the examples herein, the TCI state may refer to an UL TCI state or joint DL/LIL TCI state.

In some examples the UL beam information reporting message may comprise a DL RS resource indicator (and/or beam measurements, such as L1-RSRP) associated with (UL) TCI state(s) for which the UE has obtained a path loss estimate. As an example the DL RS resources for which the UE reports path loss estimation information (i.e. UL beam information) may be associated with a list of TCI states configured by RRC. The list of RRC TCI states may be activated for UL transmission using TCI State activation command. Thus the set of DL RS for which the path loss estimate/UL beam information is reported, may correspond to the RS included in the (UL) TCI states. In some examples the UL beam information reporting message may comprise a DL RS resource indicator (and/or beam measurements, such as L1-RSRP) associated with activated (UL) TCI state(s) for which the UE has obtained a path loss estimate.

In some examples the trigger may be that the UE has obtained a path loss measurement for at least one DL RS resource. In some examples the trigger may be that the UE has obtained a path loss measurement for at least one pair of DL RS resources (e.g. when the UE is configured for simultaneous UL transmission).

A Pair of DL RS resources may be used as reference for simultaneous UL transmission. Simultaneous UL transmission may comprise of transmitting on uplink using set of TCI states (e.g. first and second TCI state) where in the TCI states are associated with the DL RS resources of the resource pair (first resource and second resource respectively).

Thus in some examples the UE may determine that it has obtained a path loss measurement for at least one DL RS resource or pair of DL RS resources, and then send the UL beam information reporting message based on the determining.

In some examples the UL beam information reporting message may comprise information indicating whether the reported DL RS resource(s) (or the quasi-co-located (QCL) source RS) associated with the UL TCI state(s) is maintained for path loss estimation and/or information indicating whether the UE has performed the path loss estimation for the RS. In some examples, when the path loss estimation for one or more DL RS is maintained by the UE (and e.g. reported to network) the network may expect the UE to be able to perform uplink communication (and/or switch to the new uplink) using the one or more DL RS as reference for uplink transmission with less switch delay . If there is uncertainty whether the path loss is maintained or if the path loss is not maintained the switching delay may be longer.

As an example, in case of uncertainty or without information whether the UE maintains path loss for DL RS that is used as reference for UL transmission, the network, after switching the UE to use specific DL RS (associated with a TCI State) as reference for uplink communication, may need to wait the UE to perform the path loss estimate prior to the UL transmission. The path loss estimation may introduce a (or an additional) delay component for the switching time e.g. the time before the UE can be assumed to be able to use the uplink (beam) for transmission may be longer due to the path loss estimation.

By the UE sending the UL beam reporting message, the network’s uncertainty of whether the UE has path loss maintained for the one or more DL RS may be removed. Thus, when the path loss estimation for one or more DL RS is maintained by the UE (and e.g. reported to network) the UE may be expected or required to be able to perform uplink communication using the one or more DL RS as reference for uplink transmission with less switching delay (compared to the case where the path loss estimation is performed).

In some examples the UE may be configured to maintain or UE may be expected to maintain a path loss estimate for one or more of the reported DL RS resource(s) for a certain duration - for example the next X milliseconds or the next X symbol periods or the next X reference signal periods (e.g. SSB periods). The value of X may be specified (e.g. a preconfigured value) or it may be configured via signalling received from the network. The value of X may be applicable from the sending of the UL beam information reporting message - for example for X=5 the UE may maintain the path loss estimate for 5 seconds after sending the UL beam information reporting message.

In some examples the UE may be configured with value N that indicates a maximum number of the DL RS for which the path loss estimates are maintained are reported in the event-based reporting. For example, if N=4, the UE may be configured to report (and maintain) up to N=4 path loss estimates on DL RS resources that are reported in event-based reporting. In some examples, if the UE may be configured to report up to N, it may report less than N. For example, if N=4, the UE may report 1 , 2, 3, or 4 DL RS. In some examples the UL beam information reporting message may further comprise information related to set of uplink TX beams used for or available for simultaneous UL transmissions. The UL beam reporting message may comprise information indicating whether a reported pair of DL RS resources (or the QCL source RS) associated with different DL RS resource sets (e.g. non-zero point channel state information RS (NZP-CSI-RS) resource sets or SSB resource sets) associated with the (UL) TCI state(s) are also maintained for path loss estimation and/or information indicating whether the UE has performed the path loss estimation for the RS resources.

In some examples the UL beam information reporting message may include an indication that two or more of the reported DL RS resources are associated with each other. The indication may indicate that simultaneous UL transmission is valid and UE has performed path-loss estimation for the resource pair. For example, a reported DL RS resource pair may be associated as a pair with a bit-field, e.g. 1 -bit, to indicate whether the reported pair is valid for simultaneous UL transmission or not, if more than one resource is reported. In some examples, when a resource is not associated with any indication or resources are not indicated as pair, the resources may be indicated as single transmission resources. In some examples, the UE may be configured to report DL resource pair for which the path loss estimation is performed.

As mentioned previously, in some examples, after sending the UL beam information reporting message, the UE may maintain the path loss estimate for the reported DL RS resource for a certain amount of time. In such examples, the UE may consider the reported DL-RS as “known TCI state for UL switch” for the configured/specified TCI state corresponding to the reported DL-RS. Alternatively, the UE may consider the set of reported DL-RS resources as “known TCI states for the switch of set of TX beams for simultaneous UL transmissions” for the configured/specified TCI states corresponding to the reported DL-RS resources.

In some examples the event-based UL beam information reporting may be implemented when the UE is configured with unified TCI state or at least one unified TCI state is activated.

In some examples the event-based UL beam information reporting may comprise different event-based reporting modes. The different modes may be configured by the network or one mode may be used as a predefined or default mode.

In some examples, the one of the modes referred herein may be used for event-based reporting of UL beam information. In other words, there may be only one specific mode used, or only one mode may be configured to be active at a given time. A reporting mode and associated parameters may be configured (or configured and activated) based on signalling received at the UE from the network - for example using RRC signaling or RRC+MAC CE signaling.

In any of the examples herein, the set of DL RS for reporting UL beam information may be configured by the network (for example via RRC signalling) or configured and then activated by network via signalling, such as RRC and MAC CE signalling (e.g. using e.g. a MAC CE activating a specific set of RRC configured DL RS).

In some examples, the set of DL RS for reporting UL beam information may be implicitly determined. For example, the set of DL RS may correspond to the one or more (or all) of the DL RS configured for the L1-RSRP reporting. The set of DL RS may correspond to the one or more (or all) of the DL RS configured as DL RS in the TCI states. The set of DL RS may correspond to the one or more (or all) of the DL RS configured as DL RS in the activated TCI states.

In one of the modes (hereinafter referred to as a first mode) the UE may be configured with a set of DL RS, and the trigger condition for sending the UL beam information reporting message may be that the path-loss estimate has been performed for at least one DL RS in the set. The set of DL RS may be configured by the network (for example via RRC signalling) or activated by network via signalling (e.g. using e.g. a MAC CE).

In one of the modes (hereinafter referred to as a second mode), the UE may be configured to monitor a set of DL RS that are configured for measurement reporting, and the trigger condition may be that a path-loss estimate has been performed for at least one DL RS in the set.

In one of the modes (hereinafter referred to as a third mode) the UE may be configured to monitor a set of DL RS that are configured for measurement reporting and are activated TCI states for UL, and the trigger condition may be that a path-loss estimate has been performed for at least one DL RS in the set.

In one of the modes (hereinafter referred to as a fourth mode, the UE may be configured to monitor a set of DL RS that are configured for measurement reporting and are not activated TCI states for UL, and the trigger condition may be that a path-loss estimate has been performed for at least one DL RS in the set. In one of the modes (hereinafter referred to as a fifth mode) the UE may be configured to monitor a set of DL RS that are configured as transmitted SSBs for a cell, and the trigger condition may be that a path-loss estimate has been performed for at least one DL RS in the set.

In some examples all of the above modes may also be applicable for the reporting of simultaneous uplink transmission beams. In some examples in above modes, for simultaneous uplink transmission there may be multiple sets (e.g. M sets for N simultaneous uplink transmissions, where M=N in some examples) of DL RS.

In some examples the network may use an indication (e.g. a DCI indication) to activate the event based reporting mode. The indication may for example be a bit field indicating whether the UE is expected to report/initiate event-based evaluation for the reporting of UL information. In some examples the event-based reporting mode may be active/valid for a certain amount of time (e.g. K milliseconds or K symbol periods) or until the UE has reported at least one DL RS with UL information or until new UL TCI has been configured. In some examples, if the event criteria is not fulfilled within the certain amount of time, the event may become invalid.

In some examples the UL beam information reporting message may comprise an indication of whether: a reported DL RS resource indicator is monitored for path loss estimate/ and/or pathloss estimate is completed. Alternatively or additionally the indication may be part of a measurement report (such as L1-RSRP) that may comprise an indication whether or not the UE has estimated/maintains the path loss for the reported RS. This may be part of a measurement report (e.g. one additional bit); and/or an uplink control information (UCI) reporting configuration that reports DL RS for which the path loss is monitored and/or estimated; and/or a MAC CE that reports DL RS resource indicators and lists the DL RS indicators for which the path loss estimate has been obtained/and monitored.

Some examples may enable UE aided UL beam switch for faster UL switching, since the UE may indicate to the network that the UE has maintained path loss estimate for one or more DL RSs in a set of DL RS. Some examples may enable faster switching right after TCI state activation (for the DL RS(s) associated with TCI State(s) that UE has indicated that it has estimated or has estimated and maintains path loss) when the path loss estimation is known to be maintained by the UE. In some examples the network has assumption or information whether the UE has estimated or estimated and maintains path loss estimates for specific DL RS (that may be associated with a TCI state) used as reference for uplink transmission, and thus examples may enable faster switch of at least uplink communication (UL TCI state or joint DL and UL TCI ) since the uplink switching delay budget may not include the time needed for path loss estimation measurements.

If the network does not have assumption or information whether the UE has estimated or estimated and maintains path loss estimates for specific DL RS (that may be associated with a TCI state) used as reference for uplink transmission, the network may need to include the path loss estimation measurements for the switching delay budget. Longer delay may cause lower throughput, longer delays for data/control (e.g. the UE may use earlier TCI state for uplink communication that may have degraded quality) and/or it may reduce the network scheduling flexibility since the TCI state switch to another TCI State takes longer.

In some examples a user equipment may comprise means for: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

In some examples a user equipment may comprise at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the user equipment at least to: perform path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determine that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, send, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions

In some examples an access node may comprise means for: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions. In some examples an access node may comprise at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the access node at least to: receive, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

It should be understood that in some examples the apparatuses may comprise or be coupled to other units or modules etc., such as radio parts or radio heads, used in or for transmission and/or reception. Although in some examples the apparatuses have been described as one entity, different modules and memory may be implemented in one or more physical or logical entities.

It is noted that whilst some embodiments have been described in relation to 5G networks, similar principles can be applied in relation to other networks and communication systems. Therefore, although certain embodiments were described above by way of example with reference to certain example architectures for wireless networks, technologies and standards, embodiments may be applied to any other suitable forms of communication systems than those illustrated and described herein.

It is also noted herein that while the above describes example embodiments, there are several variations and modifications which may be made to the disclosed solution without departing from the scope of the present invention.

As used herein, “at least one of the following: <a list of two or more elements>” and “at least one of <a list of two or more elements>” and similar wording, where the list of two or more elements are joined by “and” or “or”, mean at least any one of the elements, or at least any two or more of the elements, or at least all the elements.

In general, the various embodiments may be implemented in hardware or special purpose circuitry, software, logic or any combination thereof. Some aspects of the disclosure may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device, although the disclosure is not limited thereto. While various aspects of the disclosure may be illustrated and described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that these blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof.

As used in this application, the term “circuitry” may refer to one or more or all of the following:

(a) hardware-only circuit implementations (such as implementations in only analog and/or digital circuitry) and

(b) combinations of hardware circuits and software, such as (as applicable):

(i) a combination of analog and/or digital hardware circuit(s) with software/firmware and

(ii) any portions of hardware processor(s) with software (including digital signal processor(s)), software, and memory(ies) that work together to cause an apparatus, such as a mobile phone or server, to perform various functions) and

(c) hardware circuit(s) and or processor(s), such as a microprocessor(s) or a portion of a microprocessor(s), that requires software (e.g., firmware) for operation, but the software may not be present when it is not needed for operation.”

This definition of circuitry applies to all uses of this term in this application, including in any claims. As a further example, as used in this application, the term circuitry also covers an implementation of merely a hardware circuit or processor (or multiple processors) or portion of a hardware circuit or processor and its (or their) accompanying software and/or firmware. The term circuitry also covers, for example and if applicable to the particular claim element, a baseband integrated circuit or processor integrated circuit for a mobile device or a similar integrated circuit in server, a cellular network device, or other computing or network device.

The embodiments of this disclosure may be implemented by computer software executable by a data processor of the mobile device, such as in the processor entity, or by hardware, or by a combination of software and hardware. Computer software or program, also called program product, including software routines, applets and/or macros, may be stored in any apparatus-readable data storage medium and they comprise program instructions to perform particular tasks. A computer program product may comprise one or more computerexecutable components which, when the program is run, are configured to carry out embodiments. The one or more computer-executable components may be at least one software code or portions of it.

Further in this regard it should be noted that any blocks of the logic flow as in the Figures may represent program steps, or interconnected logic circuits, blocks and functions, or a combination of program steps and logic circuits, blocks and functions. The software may be stored on such physical media as memory chips, or memory blocks implemented within the processor, magnetic media such as hard disk or floppy disks, and optical media such as for example DVD and the data variants thereof, CD. The physical media is a non-transitory media.

The term “non-transitory,” as used herein, is a limitation of the medium itself (i.e. , tangible, not a signal ) as opposed to a limitation on data storage persistency (e.g., RAM vs. ROM).

The memory may be of any type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as semiconductor based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory. The data processors may be of any type suitable to the local technical environment, and may comprise one or more of general purpose computers, special purpose computers, microprocessors, digital signal processors (DSPs), application specific integrated circuits (ASIC), FPGA, gate level circuits and processors based on multi core processor architecture, as non-limiting examples.

Embodiments of the disclosure may be practiced in various components such as integrated circuit modules. The design of integrated circuits is by and large a highly automated process. Complex and powerful software tools are available for converting a logic level design into a semiconductor circuit design ready to be etched and formed on a semiconductor substrate.

The scope of protection sought for various embodiments of the disclosure is set out by the independent claims. The embodiments and features, if any, described in this specification that do not fall under the scope of the independent claims are to be interpreted as examples useful for understanding various embodiments of the disclosure.

The foregoing description has provided by way of non-limiting examples a full and informative description of the exemplary embodiment of this disclosure. However, various modifications and adaptations may become apparent to those skilled in the relevant arts in view of the foregoing description, when read in conjunction with the accompanying drawings and the appended claims. However, all such and similar modifications of the teachings of this disclosure will still fall within the scope of this invention as defined in the appended claims. Indeed, there is a further embodiment comprising a combination of one or more embodiments with any of the other embodiments previously discussed.

Claims

1 . A user equipment comprising means for: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

2. The user equipment of claim 1 , wherein determining that the trigger condition has been satisfied comprises: determining that the user equipment has obtained a path loss estimate for one of: at least one downlink reference signal resource associated with the one or more uplink transmissions; or at least one pair of downlink reference signal resources associated with the one or more uplink transmissions, wherein the user equipment is configured for simultaneous uplink transmission.

3. The user equipment of claim 2, wherein the information related to one or more uplink transmissions comprises: an indicator of the at least one downlink reference signal resource or the at least one pair of downlink reference signal resources for which the user equipment has obtained a path loss measurement; or information indicating that the at least one downlink reference signal resource or the at least one pair of downlink reference signal resources is maintained for path loss estimation.

4. The user equipment of claim 3, wherein the information indicating that the at least one downlink reference signal resource or the pair of downlink reference signal resources is maintained for path loss estimation comprises information indicating a duration for which the path loss estimation is maintained.

5. The user equipment of claim 4, wherein the duration is configured based on information received from a network entity.

6. The user equipment of any of claims 2 to 5, wherein the information related to the one or more uplink transmissions comprises an indication that two or more of the at least one downlink reference signal resources are associated with each other for simultaneous uplink transmission.

7. The user equipment of any of claims 2 to 6, wherein the information related to the one or more uplink transmissions comprises information indicating that a reported pair of downlink reference signal resources associated with different downlink reference signal resource sets are maintained for path loss estimation.

8. The user equipment of any of claims 2 to 7, wherein the user equipment is configured to operate in at least one of the following modes of operation: a first mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference signal resources, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference signal resource in the set; a second mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a third mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fourth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured for measurement reporting and are not activated transmission configuration indicator states for uplink, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set; a fifth mode, wherein the one or more downlink reference signal resources comprises a set of downlink reference resources configured as transmitted synchronization signal blocks, and wherein the trigger condition comprises that a path loss estimate has been obtained for at least one downlink reference resource in the set.

9. The user equipment of claim 8, wherein the means is further for: receiving an indication from the access node indicating one of the modes of operation and activating the mode of operation based on the received indication.

10. The user equipment of any preceding claim, wherein the means is further for: determining that the user equipment is configured with a unified transmission configuration indicator state or at least one unified transmission configuration indicator state is activated, wherein sending the uplink beam information reporting message is further based on the determining that the user equipment is configured with the unified transmission configuration indicator state or the at least one unified transmission configuration indicator state is activated.

11. The user equipment of any preceding claim, wherein the information related to the one or more uplink transmission comprises at least one of: an indication that a reported downlink reference signal resource is monitored for path loss estimation and/or that a path loss estimate has been obtained; an identifier reporting configuration that indicates that a reported downlink reference signal resource is monitored for path loss estimation or that a path loss estimation has been obtained; or a medium access control control element comprising information indicating the downlink reference signal resources that are monitored for path loss estimation or for which a path loss estimate has been obtained.

12. The user equipment of any preceding claim, wherein the means is further for: receiving, from the access node, information indicating at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources.

13. The user equipment of any preceding claim, wherein the at least one downlink reference signal comprises a synchronization signal block and/or channel state information reference signal.

14. The user equipment of any preceding claim, wherein the one or more downlink reference signals are associated with one or more transmission configuration indicator states for uplink transmission

15. An access node comprising means for: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

16. The access node of claim 15, further comprising means for: sending, to the user equipment, an indication of one of the modes of operation for performing uplink beam information reporting.

17. The access node of claim 15 or 16, further comprising means for: based on the uplink beam information reporting message, performing uplink beam switching for the user equipment to determine at least one new uplink beam, wherein the at least one new uplink beam is associated with at least one of the one or more downlink reference signal resources; and sending, to the user equipment, information indicating the determined at least one new uplink beam.

18. A user equipment comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the user equipment at least to: perform path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determine that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, send, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

19. An access node comprising at least one processor and at least one memory storing instructions that, when executed by the at least one processor, cause the access node at least to: receive, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.

20. A method performed at a user equipment, the method comprising: performing path loss measurements on one or more downlink reference signal resources, wherein the one or more downlink reference signal resources are associated with one or more uplink transmissions; based on the path loss measurements, determining that a trigger condition has been satisfied; and based on determining that the trigger condition has been satisfied, sending, to an access node, an uplink beam information reporting message comprising information related to the one or more downlink reference signal resources for one or more uplink transmissions.

21. A method performed at an access node, the method comprising: receiving, from a user equipment, an uplink beam information reporting message comprising information related to one or more downlink reference signal resources for one or more uplink transmissions.