Uplink beam management with limited signaling overhead

Abstract

A method (700) in a wireless device (120) for facilitating determining at least one transmit beam to be used in connection with a transmit receive point (115a) or an access point in a wireless network (110), the method comprising: receiving (714) an uplink reference signal, UL RS, configuration grouped into a plurality of sets of UL RS resources; receiving (716) an activation trigger indicating at least one set of UL RS resources from the configured set of UL RS resources; transmitting on a plurality of UL RS resources in the one or more indicated UL RS resource sets (718); evaluating (718.1), for one or more indicated sets of UL RS resources, a predetermined implicit drop rule dependent on a characteristic of the wireless device and deciding to omit transmissions on at least one of the UL RS resources therein; and receiving (722) an instruction for using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources.

Description

Technical Field

[0001] This disclosure relates to the field of cellular communication between multiple antenna transceivers. Specifically, this disclosure proposes a technique for determining a beam suitable for communication from a wireless device capable of transmitting simultaneously at multiple antenna panels to a network node. Background Technology

[0002] In the high-frequency range (FR2), multiple RF beams can be used to transmit and receive signals at the base station (gNB) and user equipment (UE). For each downlink transmit (DL Tx) beam from the gNB or a transmit-receive point (TRP) associated with the gNB, there is typically an associated best-receive (Rx) beam used to receive signals from the DL beam at the UE. The DL Tx beam and the associated UE Rx beam form a beam pair. Beam pairs can be identified through a so-called beam management process in the NR.

[0003] Although not explicitly stated in the NR specification, beam management can be considered to consist of three distinct processes, such as... Figure 2 Schematic diagram:

[0004] P1: The objective is to use the wide gNB Tx beams 211, 212, and 213 from gNB 110, covering the entire corner sector, to find an approximate direction for UE 120. UE 120 can use a single Rx beam 221.

[0005] P2: The purpose is to refine the gNB Tx beam by performing a new beam search around the coarse direction found in P1, i.e., by transmitting the regular (narrow) Tx beams 214, 215, 216. UE 120 can use a single Rx beam 222.

[0006] P3: Used for UEs with simulated beamforming to allow them to find a suitable UE Rx beam. In P3, UE 120 receives on multiple beams 223, 224, and 225, while gNB 110 transmits on a constant beam 217, which is preferably a conventional (narrow) beam. During P3, aperiodic CSI-RS transmitted in a narrow gNB beam can be used.

[0007] A UE can be equipped with multiple different UE panels, and different UE panels can support different numbers of UE beams. In this sense, a panel is a set of associated transmit or receive antennas, as described in detail in the applicant's previous publication PCT / EP2022 / 076975. Furthermore, each panel can support a dynamically varying number of UE beams, i.e., if the beamwidth is configurable.

[0008] The current 3GPP NR specification does not support UL beam management in a manner suitable for UEs with multiple UE panels, especially when different UE panels support different numbers of beams and / or different numbers of ports. For example, according to the NR specification, it can be understood that if a UE can only transmit from one panel at a time, then it can only be configured on a Sounding Reference Signal (SRS) resource set used for beam management. Therefore, such an SRS resource set should then be used for all different UE panels, regardless of the UE panel's structure (e.g., the number of beams supported by the UE panel, the number of TX / TRX chains supported by the UE panel, etc.).

[0009] Furthermore, even if multiple SRS resource sets with beamManagement purposes are configured for UEs capable of transmitting using multiple UE panels at once, the network in NR currently cannot know which (or which) UE panels the UE will use for the UL beam management process; nor can the network rely on reported panel-related information to definitively determine which panel it is associated with. Therefore, in settings with different numbers of UE beams for different UE panels, the network cannot know how many beams the UE wants to transmit, and thus cannot know on how many SRS resources the UE wants to transmit on.

[0010] Furthermore, commercial NR time-division duplex (TDD) systems are known to suffer from persistent SRS capacity deficiencies to varying degrees. This SRS capacity issue is expected to become even more severe when UL beam management processes are used in millimeter-wave TDD systems. Therefore, there is a need to reduce SRS overhead in NR systems. Summary of the Invention

[0011] One object of this disclosure is to provide an uplink beam management procedure that utilizes available UL RS resources more efficiently. Another object is to provide an uplink beam management procedure in which a limited number of signaling signals are sufficient to configure the UL RS resources to be used. Another object is to provide an SRS-based uplink beam management procedure. Yet another object is to provide an uplink beam management procedure suitable for UEs equipped with multiple antenna panels. In particular, the uplink beam management procedure should be resource efficient, especially even in settings where the number of beams to be emitted varies between the UE's panels.

[0012] At least some of these objectives are achieved by the invention as defined in the independent claims. The dependent claims relate to advantageous embodiments.

[0013] In a first aspect of this disclosure, the inventors propose a method implemented in a wireless device suitable for facilitating the determination of at least one transmit beam to be used in association with a transmit-receive point (TRP) or access point (AP) in a wireless network. The method includes: receiving from the network a UL RS configuration grouped into a plurality of uplink reference signal (UL RS) resource sets; receiving from the network an activation trigger indicating at least one UL RS resource set from the configured UL RS resource sets; transmitting on a plurality of UL RS resources in one or more indicated UL RS resource sets; and receiving from the network instructions for communicating with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. According to the first aspect of this disclosure, the method further includes: evaluating a pre-agreed implicit drop rule for one or more indicated UL RS resource sets and determining to omit transmission on at least one UL RS resource in those UL RS resources.

[0014] Due to the implicit discarding rules pre-agreed between the wireless device and the wireless network, the network can broadly define the UL RS configuration to ensure determinism that redundant UL RS resources will be discarded. For example, the network can configure all UL RS resource sets with an equal number of UL RS resources, even though it has knowledge about the UE (e.g., the ability indicated by the UE) that it is clear from this knowledge that the full number will only be used in one of the UL RS resource sets. If all UL RS resource sets have an equal number of UL RS resources, then only the first UL RS resource set must be defined by explicit signaling, while the second, third, and other UL RS resource sets can reference the first UL RS resource set; the reference can be an explicit signaling element or can implicitly follow syntax rules.

[0015] In addition to lower signaling overhead, the method according to the first aspect is also used to release UL RS resources. Where the network is able to predict which UL RS resources a wireless device will discard based on implicit discard rules or explicit indications from the wireless device, these UL RS resources can be allocated to other devices served by the network.

[0016] The method described in the first aspect can also be a tool for reducing interference. In particular, omitting unnecessary transmissions on UL RS resources can slightly reduce inter-cell interference.

[0017] In a second aspect of this disclosure, a method implemented in a network node of a wireless network is provided, the method being adapted to facilitate the determination of at least one transmit beam to be used by a wireless device in relation to a transmit-receive point (TRP) or access point (AP) in the wireless network. The method includes: sending to the wireless device a UL RS configuration grouped into a plurality of uplink reference signal (UL RS) resource sets; sending to the wireless device an activation trigger indicating at least one UL RS resource set from the configured UL RS resource sets; performing measurements on a plurality of UL RS resources in one or more indicated UL RS resource sets; selecting one or more UL RS resources on which measurements have already been performed; and sending to the wireless device an instruction for communicating with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. According to the second aspect, measurements on at least one UL RS resource in one or more indicated UL RS resource sets are omitted based on a pre-agreed implicit discard rule depending on the characteristics of the wireless device.

[0018] Similar to the approach in the first aspect, the network-side approach outlined above reduces or limits the signaling overhead generated by UL RS configuration, and it frees up UL RS resources at the system level. Specifically, this enables the network to predict which UL RS resources a wireless device will discard and allocate them to other devices.

[0019] According to the third and fourth aspects of this disclosure, a wireless device and a network node operating according to the above-described methods are also provided. Generally, wireless devices and network nodes share the effects and advantages of these methods, and they can be implemented using corresponding degrees of technological variation.

[0020] This disclosure also describes a computer program containing instructions for causing a computer, or particularly a wireless device or network node, to perform the methods described above. The computer program may be stored or distributed on a data carrier. As used herein, "data carrier" can be a temporary data carrier, such as modulated electromagnetic waves or light waves, or it can be a non-temporary data carrier. Non-temporary data carriers include volatile and non-volatile memories, such as permanent and non-permanent storage media of magnetic, optical, or solid-state types. Still within the scope of "data carrier," such memory can be fixedly mounted or portable.

[0021] The implicit drop rules mentioned above can depend on the characteristics of the wireless device. In different embodiments, this characteristic can be the number of beams supported by the panel of the wireless device, the number of beams of a given type supported by the panel, the number of ports supported by the panel, or other attributes known directly or indirectly to the network and the wireless device.

[0022] In some embodiments, a special uplink beam management capability is provided, namely a data structure through which a wireless device can instruct it to apply implicit drop rules to any UL RS configuration it will receive from the network. This informs the network that it can satisfy a broad definition of the UL RS configuration and hands over fine-tuning (tweening) of the action of the drop rules. The special uplink beam management capability may also include information related to the wireless device's panel.

[0023] In some embodiments, the wireless device indicates to the network the association between the TRP / AP and the wireless device's panel, where each panel represents a set of antennas. This can guide the network's allocation of UL RS resources and can further help it more accurately predict which UL RS resources implicit drop rules will affect.

[0024] In some embodiments, the activation trigger includes an indication of the beam type to be used to transmit UL RS resources. Since the number of beams (per panel) supported by the wireless device can differ for different beam types, an indication of the beam type to be used helps network nodes allocate UL RS resources with greater accuracy, particularly regarding their total number.

[0025] For the purposes of this disclosure, a “beam” can be defined by UL RS resources. More specifically, a UE may need to emit a set of UL RS resources, where each UL RS resource is emitted on a separate beam. The network can then schedule the UE on one of the emitted UL RS resources, for example, based on a UL RS index that has a one-to-one relationship with the corresponding beam.

[0026] Furthermore, in this disclosure, the terms User Equipment (UE) and Radio Equipment are used interchangeably.

[0027] Generally, all terms used in the claims should be interpreted according to their ordinary meaning in the technical field, unless otherwise expressly defined herein. All references to “a / the element, device, component, apparatus, step, etc.” should be openly interpreted as referring to at least one instance of an element, device, component, apparatus, or step, etc., unless otherwise expressly stated. The steps of any method disclosed herein need not be performed in the exact order described unless expressly stated otherwise. Attached Figure Description

[0028] Various aspects and embodiments will now be described by way of example with reference to the accompanying drawings, in which:

[0029] Figure 1 This shows wireless devices in the coverage area of ​​a single TRP base station and a multi-TRP base station;

[0030] Figure 2 The diagram illustrates three example beam management processes;

[0031] Figure 3 The diagram illustrates uplink beam management;

[0032] Figure 4 This is a perspective view of a UE with four panels;

[0033] Figure 5 This is a schematic diagram of a UE with three panels orthogonally oriented to improve coverage, wherein the UE has a baseband chain available for use and can be connected to one of the panels at a time;

[0034] Figure 6 An example use case of this disclosure is described, namely a communication setup of a four-panel UE operating in a multi-TRP / D-MIMO millimeter-wave deployment;

[0035] Figure 7 This is a sequence diagram illustrating the method for determining the beams used for communication between network nodes and UEs; and

[0036] Figures 8 to 10 An example handover network is shown for a UE with four panels, where up to two panels can be used for simultaneous transmission. Detailed Implementation

[0037] Aspects of this disclosure will now be described more fully below with reference to the accompanying drawings, which illustrate certain embodiments of the invention. However, these aspects may be embodied in many different forms and should not be construed as limiting; rather, these embodiments are provided by way of example so that this disclosure will be thorough and complete, and will fully convey the scope of all aspects of the invention to those skilled in the art. Throughout the description, the same numerals refer to the same elements.

[0038] System Overview

[0039] Figure 1 In the first deployment, wireless device 120 is located at a base station 110 with a single TRP 115. Figure 1 The upper part) and a base station 110 with two TRP 115a and 115b ( Figure 1The lower part of the coverage area. Base station 110 is configured as a network node in the radio access network within a cellular telecommunications system (such as a 3GPP NR system).

[0040] This figure schematically illustrates the components of a wireless device 120 according to an embodiment in the form of multiple functional units. The processing circuitry 122 is provided using any combination of one or more of a suitable central processing unit (CPU), multiprocessor, microcontroller, digital signal processor (DSP), etc., capable of executing software instructions stored in a computer program product 124 (e.g., in the form of storage medium 123). The processing circuitry 122 may also be provided as at least one application-specific integrated circuit (ASIC) or field-programmable gate array (FPGA). Specifically, the processing circuitry 122 is configured to cause the wireless device 120 to perform the following references. Figure 7 A set of publicly disclosed operations or steps. For example, storage medium 123 may store this set of operations, and processing circuitry 122 may be configured to retrieve the set of operations from storage medium 123 to cause wireless device 120 to execute the set of operations. This set of operations may be provided as a set of executable instructions. Therefore, processing circuitry 122 is arranged to execute instructions that will be referenced to... Figure 7 The described method facilitates the determination of the beam to be used when the wireless device 120 communicates with the network node 110. Storage medium 123 may also include persistent storage devices, which may be any single or combination of magnetic storage, optical storage, solid-state storage, or even remotely mounted storage.

[0041] Wireless device 120 may also include a communication interface 125 for communicating with network node 110. Thus, communication interface 125 may include one or more transmitters and receivers, comprising analog and digital components. Processing circuitry 122 controls the general operation of wireless device 120, for example by sending data and control signals to communication interface 125 and storage medium 123, by receiving data and reports from communication interface 125, and by retrieving data and instructions from storage medium 123. Other components and related functions of wireless device 120 are omitted so as not to obscure the concepts presented herein.

[0042] Figure 1The components of the network node 110 according to the embodiment are also illustrated in the form of multiple functional units. Each network node 110 includes a front-end unit 111 and at least one TRP 115. The front-end unit 111 may be located at the same location as or away from the TRP 115. In the front-end unit 111, processing circuitry 112 is provided using any combination of one or more of a suitable CPU, multiprocessor, microcontroller, DSP, etc., capable of executing software instructions stored in a computer program product 114 (e.g., in the form of storage medium 113). The processing circuitry 112 may also be provided as at least one ASIC or FPGA. In particular, the processing circuitry 112 is configured to cause each network node 110 to perform the following reference Figure 7 A set of publicly disclosed operations or steps. For example, storage medium 113 may store this set of operations, and processing circuitry 112 may be configured to retrieve the set of operations from storage medium 113 to cause wireless device 110 to execute the set of operations. This set of operations may be provided as a set of executable instructions. Therefore, processing circuitry 112 is arranged to execute instructions that will be referenced to... Figure 7 The method described is for determining the beam to be used when the network node 110 communicates with the wireless device 120. The storage medium 113 may also include persistent storage, as illustrated above.

[0043] Network node 110 may also include a communication interface, which includes a TRP 115, for communicating with wireless device 120. Thus, the communication interface may include one or more transmitters and receivers, comprising analog and digital components. Processing circuitry 112 controls the general operation of network node 110, for example by sending data and control signals to the communication interface (which has TRP 115) and storage medium 113, by receiving data and reports from the communication interface, and by retrieving data and instructions from storage medium 113. Other components and related functions of network node 110 are omitted so as not to obscure the concepts presented herein.

[0044] SRS

[0045] Before describing the inventors' contributions, some background concepts will be reviewed. In 3GPP NR, the Sounding Reference Signal (SRS) is used to provide Channel State Indication (CSI) to the gNB in ​​the UL. Uses of the SRS include, for example, deriving appropriate transmit / receive beams and / or performing link adaptation (i.e., setting the transmission rank and MCS). The SRS can also be used to select MIMO precoding for DL ​​(e.g., for PDSCH transmissions) and UL (e.g., for PUSCH transmissions).

[0046] In LTE and NR, SRS is configured via the Radio Resource Control (RRC) protocol, a portion of which can be updated via MAC-CE signaling (to reduce latency). This configuration includes, for example, SRS resource allocation (physical mapping and the sequence to be used) and temporal behavior (aperiodic, semi-persistent, or periodic). For aperiodic SRS transmissions, the RRC configuration does not activate SRS transmissions from the UE; instead, a dynamic activation trigger is sent from the gNB in ​​the DL via a DCI in the PDCCH, instructing the UE to transmit SRS once at a predetermined time.

[0047] When configuring SRS transport, gNB configures the collection of SRS resources and the collection of SRS resource sets through the SRS-Config IE, where each SRS resource set contains one or more SRS resources.

[0048] The resource usage configured by the RRC parameter "usage" sets constraints and assumptions about resource attributes (see 3GPP TS38.214 for further details). SRS resource sets can be configured with one of four different uses assigned to the parameter "usage": "antennaSwitching", "codebook", "nonCodebook", and "beamManagement".

[0049] 1. An SRS resource set configured for “antenna switching” is used for reciprocity-based DL precoding (i.e., for broadcasting the channel in the UL so that the gNB can use reciprocity to set up the appropriate DL precoder). It is expected that the UE will transmit one SRS port for each UE antenna port.

[0050] 2. The SRS resource set configured with a purpose "codebook" is used for codebook-based UL transmission (i.e., for transmitting signals to different UE antennas and helping the gNB determine / signal the appropriate UL precoder, transmission rank, and MCS for PUSCH transmission). Up to two SRS resources exist in the SRS resource set with the purpose "codebook." However, how the SRS ports are mapped to the UE antenna ports depends on the UE implementation and is unknown to the gNB.

[0051] 3. A set of SRS resources configured for "non-codebook" use is employed for NCB-based UL transmissions. Specifically, the UE transmits one SRS resource for each candidate beam (the suitable candidate beam is determined by the UE based on CSI-RS measurements in the DL, and therefore reciprocity needs to be maintained). The gNB can then determine which (or which) UL beams the UE should apply for PUSCH transmissions by indicating a subset of these SRS resources. One UL layer is transmitted for each indicated SRS resource. Note that how the UE maps SRS ports to antenna ports depends on the UE implementation and is unknown to the gNB.

[0052] 4. An SRS resource set configured for "beam management" is used (primarily for bands above 6 GHz, i.e., for FR2) to evaluate different UE beams for the analog beamforming array. The UE transmits one SRS resource for each analog beam, and the gNB performs RSRP measurements for each transmitted SRS resource, thereby determining the appropriate UE beam to be reported to the UE.

[0053] SRS antenna switching

[0054] Ideally, the gNB would sound all UE antennas, meaning it transmits SRS from that antenna, allowing the gNB to estimate the channel between the UE antenna and the antenna at the gNB. However, since equipping a UE with numerous transmit ports is typically costly, SRS antenna switching was introduced in 3GPP NR Release 15 for several different UE architectures with a greater number of receive chains than transmit chains. If a UE supports antenna switching, it will report this via UE capability signaling.

[0055] As specified in 3GPP TS 38.306, version 15 UEs can use IE supportedSRS-TxPortSwitch to report the following antenna switching capabilities:

[0056] -t1r2,

[0057] -t1r4,

[0058] -t2r4,

[0059] -t2r2,

[0060] -t4r4,

[0061] -t1r4-t2r4.

[0062] For example, if a UE reports t1r2 in its UE capability signaling, it means that it has two receive antennas (i.e., two receive chains), but can only transmit from one of those antennas (i.e., one transmit chain) at a time with support for antenna switching. In this case, two single-port SRS resources can be configured for the UE, allowing it to transmit from both receive ports using a single transmit port with an antenna switch in between.

[0063] Additional UE capabilities were introduced in NR Rel-16, where the IE supportedSRS-TxPortSwitch-r1610 (supported SRS-Tx port switching-r1610) can have the following values:

[0064] -t1r1–t1r2,

[0065] -t t1r1–t1r2–t1r4,

[0066] -t1r1–t1r2–t2r2–t2r4,

[0067] -t1r1–t2r2,

[0068] -t1r1–t2r2–t4r4,

[0069] -t1r1–t1r2–t2r2–t1r4–t2r4.

[0070] This IE can be used to indicate that a UE is configured with one or more SRS resource sets for the purpose of "antenna switching," but only a subset of all UE antennas are activated. For example, the UE capability t1r1-t1r2 means that the gNB can configure one single-port SRS resource for each SRS resource set for the purpose of "antenna switching" (same as without antenna switching capability) or two single-port SRS resources (same as the aforementioned capability "t1r2"). In this case, if the UE is configured with a single SRS resource (without antenna switching), it will only activate one of its two antennas, which will save UE power consumption at the cost of reduced channel knowledge at the gNB (because the gNB can only estimate the channel between itself and the UE based on one of the two UE antennas).

[0071] For SRS resources used for "antenna switching" by UEs with fewer transmit chains than receive chains, a guard period must be configured between SRS resources to account for Tx handover transients. For subcarrier spacing below 120 kHz, the guard period is one OFDM symbol, while for subcarrier spacing of 120 kHz, the guard period is two OFDM symbols. This means that the UE is expected to be able to switch antennas within one or two OFDM symbols depending on the subcarrier spacing.

[0072] Multibeam operation

[0073] Beam management process

[0074] In the high-frequency range (FR2), multiple RF beams can be used to transmit and receive signals at the gNB and the UE. For each DL Tx beam from the gNB, there is typically an associated optimal UE Rx beam used to receive signals from the DL beam. The DL beam and the associated UE Rx beam form a beam pair. Beam pairs can be identified through a so-called beam management process in the NR.

[0075] DL beams are typically identified by associated DL reference signals (RS) transmitted periodically, semi-persistently, or aperiodically within the beam. DL RSs used for this purpose can be synchronization signals (SS) and physical broadcast channel (PBCH) blocks (SSBs) or channel state information RSs (CSI-RS), or replacements for any of these signals in future 6G specifications. By measuring all DL RSs, the UE can determine and report the optimal DL beam for DL ​​transmission to the gNB. The gNB can then transmit bursts of DL-RS within the reported optimal DL beam to allow the UE to evaluate candidate UE Rx beams.

[0076] Although not explicitly stated in the NR specification, beam management has been divided into three processes, such as Figure 2 Schematic diagram:

[0077] P-1: The objective is to use the wide gNB Tx beams 211, 212, and 213 from gNB 110, covering the entire corner sector, to find an approximate direction for UE 120. UE 120 can use a single Rx beam 221.

[0078] P-2: The purpose is to refine the gNB Tx beam by performing a new beam search around the coarse direction found in P-1, i.e., by transmitting the regular (narrow) Tx beams 214, 215, 216. UE 120 can use a single Rx beam 222.

[0079] P-3: For UEs with simulated beamforming to allow them to find a suitable UE Rx beam. In P-3, UE120 receives on multiple beams 223, 224, 225, while gNB 110 transmits on a constant beam 217, which is preferably a conventional (narrow) beam.

[0080] P-1 is expected to utilize a beam with a relatively large beamwidth, where a beam reference signal is periodically transmitted and shared among all UEs in the cell. Typically, the reference signal used for P-1 is a periodic CSI-RS or SSB. The UE then reports N optimal beams and their corresponding RSRP values ​​to the gNB.

[0081] It is expected that P-2 will use a non-periodic / or semi-persistent CSI-RS transmitted in narrow beams 214, 215, and 216 around the rough direction found in P-1.

[0082] P-3 is expected to use non-periodic or semi-persistent CSI-RS, repeatedly transmitted in a narrow gNB beam 217. An alternative approach is to allow the UE to determine the appropriate UE Rx beam based on periodic SSB transmissions. Since each SSB consists of four OFDM symbols, up to four UE Rx beams 223, 224, and 225 can be evaluated during each SSB burst transmission. One advantage of using SSBs instead of CSI-RS is that the additional overhead of CSI-RS transmissions is eliminated.

[0083] Beam indication

[0084] In NR, several signals can be transmitted from different antenna ports of the same base station. These signals can have the same large-scale properties, such as Doppler shift / spread, average delay spread, or average delay. These antenna ports are then referred to as quasi-co-located (QCL).

[0085] If the UE knows that both antenna ports are QCL for a certain parameter (e.g., Doppler spread), the UE can estimate that parameter based on one antenna port and apply that estimate to receive signals on the other antenna port. For example, a QCL relationship can exist between the Tracking RS (TRS) and the PDSCH DMRS. When the UE receives the PDSCH DMRS, it can use measurements already taken on the TRS to assist in DMRS reception.

[0086] Information regarding assumptions made regarding QCL is signaled from the network to the UE. In NR, four types of QCL relationships are defined between the source RS and the destination RS:

[0087] Type A: {Doppler frequency shift, Doppler spread, average delay, delay spread}

[0088] Type B: {Doppler frequency shift, Doppler spread}

[0089] Type C: {Average delay, Doppler shift}

[0090] Type D: {Spatial Rx parameter}

[0091] QCL Type D was introduced in 3GPP NR to facilitate beam management using analog beamforming and is referred to as Spatial QCL. There is currently no strict definition of Spatial QCL, but it is understood that if two transmit antenna ports are spatially QCL, the UE can use the same Rx beam to receive them. This is helpful for UEs using analog beamforming to receive signals, as the UE needs to adjust its Rx beam in a certain direction before receiving a specific signal. If the UE knows that the signal is spatially QCL with some other signal it has previously received, then it can safely use the same Rx beam to also receive that signal.

[0092] In NR, a "beam indicator" can be used to indicate to the UE the spatial QCL relationship for DL ​​or UL signals / channels. The "beam indicator" is used to help the UE find the appropriate Rx beam for DL ​​reception and / or the appropriate Tx beam for UL transmission. In NR, the "beam indicator" for DL ​​is transmitted to the UE by indicating the Transmission Configuration Indicator (TCI) status, while in UL, the "beam indicator" can be transmitted by indicating DL-RS or UL-RS as a spatial relationship (in NR Releases 15 / 16) or a TCI status (in NR Release 17).

[0093] UL Beam Management

[0094] Some UEs may have analog beamformers that lack beam correspondence or have poor beam correspondence (i.e., Tx / Rx correspondence), implying that DL / UL reciprocity cannot always be used to determine the beams used for these beamformers. For such UEs, the UE beams used for UL cannot be derived from the DL reference signal-based beam management process described above. To address such UEs, UL beam management has been included in the NR standard specification since version 15. The main difference between regular beam management and UL beam management is that UL beam management utilizes an uplink reference signal instead of a DL reference signal. The UL reference signal already agreed upon for UL beam management is the Sounding Reference Signal (SRS) in 3GPP NR; other reference signals may be used for this purpose according to future 6G specifications.

[0095] Figure 3The diagram schematically illustrates two UL beam management procedures supported in NR: U2 and U3. The U2 procedure (upper half) is performed by the UE 120 transmitting a burst of SRS resources in a UE Tx beam 321 and having the gNB's TRP 110 evaluate different TRP Rx beams 311, 312, 313, 314, and 315. The U3 procedure (lower half) allows the UE to find a suitable UE Tx beam by transmitting different SRS resources in different UE Tx beams 322, 323, 324, 325, and 326 while maintaining a constant beam 316 in TRP 110.

[0096] Even if the UE has a beam mapping, UL beam management can still be useful. More precisely:

[0097] - It can be argued that the combined DL beam management process and UL beam management process require less overhead and latency compared to using the DL beam management process alone.

[0098] The so-called "uplink-only" node deployment is a hot topic in 3GPP discussions, as such deployments are said to improve UL coverage in a cost-efficient manner, especially at higher frequencies. "UL-only" network nodes are equipped with UL capabilities but lack or have very limited downlink capabilities. In this case, since "UL-only" nodes cannot transmit DL reference signals, the beampup link between the UE and the "UL-only" node must be based on the UL beam management process.

[0099] In D-MIMO, there will be many different access points (APs) or transmit points (TRPs) in a small area, and each AP / TRP may be equipped with multiple different beams. If DL beam management is used to determine the suitable AP / TRP and the corresponding AP / TRP beam to the UE, a significant amount of reference signal overhead is required, which has been identified as a problem for D-MIMO. Therefore, it has been internally recommended that AP / TRP selection and corresponding beam selection should preferably be based on ULSRS transmissions from the UE (which can then be used to determine the suitable AP / TRP and corresponding AP / TRP beam for that UE).

[0100] Therefore, it is possible that UL beam management will play a more significant role in advanced 5G and 6G applications.

[0101] UE Simulated Beamforming Architecture

[0102] For a UE, signals can arrive and be emitted from all different directions, which makes it advantageous to have an antenna implementation at the UE that, in addition to a high-gain narrow beam, has the potential to produce near-omnidirectional coverage. One way to increase omnidirectional coverage at the UE is to install multiple panels and point these panels in different directions, which is typical of commercial UEs. However, to reduce cost and energy consumption, some of these UEs can only transmit from one UE panel at any given time.

[0103] Figure 4 An example of a real-world UE 120 with two baseband chains (one baseband chain per polarization) 122 is illustrated, which are used to switch between four different dual-polarized panels 126. Each panel 126 is operable to transmit a beam in a direction typically corresponding to a half-plane of the main transmit direction entering the panel. More specifically, antennas in a panel 126 can be oriented parallel to each other in a common direction. Often, although not necessary, antennas in a panel 126 are physically close together; for example, the distance between antennas in a panel 126 is less than the distance to antennas in any other panel. Furthermore, antennas in a panel 126 can be fed RF signals at a common input point, which can be both connected to and disconnected from baseband chains 122.

[0104] Figure 5 A wireless device 120 is shown, having three panels 126 orthogonally oriented to improve spherical coverage. The wireless device has two baseband chains 122 available, which can be connected to one of the panels 126 at a time. This capability is... Figure 5 The diagram illustrates an analog switch. Furthermore, panels 126 differ from each other in the maximum number of TX / RX chains and the number of antenna elements. In the diagram, the diagonal symbols within panel 126 indicate antenna elements with a first polarization, and the anti-diagonal symbols indicate antenna elements with a second polarization different from the first polarization.

[0105] Regarding a similar UE architecture, the following demonstration document describes how antenna switching can be used to switch between three UE panel modules M1, M2, and M3:

[0106] - Qualcomm Technologies, Inc., Breaking the Wireless Barriers to Mobilize 5G NR mmWave, May 2019, downloaded from https: / / www.qualcomm.com / content / dam / qcomm-martech / dm-assets / documents / breaking_the_wireless_barriers_to_mobilize_5g_nr_mmwave.pdf

[0107] Commercial UEs can generate beams with different beamwidths on their UE panels, as illustrated in Table 1.

[0108]

[0109] A widely adopted solution in commercial UEs is to generate a wider beam by temporarily disabling one or more power amplifiers (PAs) on the panel. This obviously has a negative impact on available output power. However, it is possible to mitigate the output power loss when generating a wide beam by applying dual-polarization beamforming, such as array-size-invariant (ASI) beamforming. What is useful for the UE is to generate a wide beam for the panel during the beam scanning process in order to first find a coarse direction to the serving AP / TRP, which will allow the UE to select and activate the appropriate UE panel. In the example in Table 1, the UE can generate one wide beam, five half-width (or half-width) beams, and nine narrow beams for each panel.

[0110] Because different UEs may have panel switching networks with different layouts, UEs may differ in terms of the UE panels / beams that can be used for simultaneous transmission or simultaneous reception. Figure 8 , 9 Figures 1 and 10 schematically depict three examples illustrating this variation among UEs.

[0111] exist Figure 8 In this configuration, the two upper UE panels 126a and 126b cannot be used for simultaneous DL / UL transmit / receive because they share the upper transceiver chain 122a. Similarly, the two lower UE panels 126c and 126d cannot be used for simultaneous DL / UL transmit / receive because they share the lower transceiver chain 122b. Therefore, the exhaustive list of all simultaneous transmit / receive panel pairs is: {126a, 126c}, {126b, 126c}, {126a, 126d}, and {126b, 126d}. All other UE panel combinations are excluded. Figure 8 The panel switching network in the model can be characterized as a balanced panel switching network.

[0112] exist Figure 9 In the middle, the upper UE panel 126a has an upper transceiver chain 122a leading to itself. However, the three lower UE panels 126b, 126c, and 126d cannot be used for simultaneous DL / UL transmission / reception because they share the lower transceiver chain 122b. Considering the unequal association between the panels and the transceiver chain, Figure 9 The panel switching network in the model can be characterized as an unbalanced panel switching network.

[0113] Finally, Figure 10 The diagram illustrates a panel switching network with a central universal switch 127, operable to connect any UE panel 126 to any transceiver chain 122. Therefore, Figure 10 The panel switching network in the model can be characterized as a fully flexible panel switching network.

[0114] Simultaneous transmission from multiple UE panels

[0115] In the current NR, the UE can signal support for the UL beam management process by indicating the uplink beam management capability during UE capability signaling. This capability is defined in 3GPP TS 38.331 as follows:

[0116] "Support for beam management for UL is defined. This capability signaling includes the following parameters:"

[0117] `maxNumberSRS-ResourcePerSet-BM` indicates the maximum number of SRS resources configurable for beam management per SRS resource set supported by the UE.

[0118] As part of this capability, the UE can use the parameter maxNumberSRS-ResourcePerSet-BM to indicate the maximum number of supported SRS resources for each SRS resource set with purpose beam management. This parameter can be used as an indication of the number of narrow beams the UE panel has. However, note that only a single value can be reported, so it is not possible to indicate different numbers of supported beams for different UE panels or different numbers of beams for different beamwidths.

[0119] Up to Release 17 of 3GPP NR, discussions regarding UL transmissions for FR2 primarily focused on UEs capable of single-panel transmission, i.e., transmission from a single UE panel rather than multiple panels at each time instance. However, Release 18 has agreed to support two different simultaneous multi-panel transmission (STxMP) schemes: Spatial Domain Multiplexing (SDM), where different layers are transmitted from two different UE panels, and Single Frequency Network (SFN) transmission, where the same layer is transmitted from two different UE panels.

[0120] Uplink beam management method

[0121] Figure 6 An example use case of this disclosure is depicted, in which a UE 120 with four panels operates in a multi-TRP / D-MIMO millimeter-wave deployment. More specifically, the UE 120 with four panels is located at the intersection of the coverage areas of TRPs 115a, 115b, 115c, and 115d. The radio device 120 is configured to operate in a millimeter-wave (or Asia-Pacific Hertz) band, or more generally in any band using analog beamforming. Each panel is operable to transmit beams 621, 622, 623, and 624 in directions typically corresponding to the half-plane of the main transmission direction entering each panel. Specifically, different UE panels are associated with different TRPs / APs 115 in the sense that a particular UE panel is optimally positioned to receive from that TRP / AP, and / or the UE 120 has indicated such an association to the network (without specifying a reason).

[0122] Among other things, this disclosure addresses the stage where the network has already determined suitable TRPs / APs for the UE and / or at least one suitable beam for each TRP / AP, for example by relying on some degree of channel reciprocity when processing transmitted UL signals / channels, or based on TRP / AP beam reports (e.g., associated with previously performed P1 or P2 procedures). Following this, the next step is to determine suitable UE beams for each identified serving TRP / AP. Note that even if the UE can only transmit simultaneously on a subset of its available panels—which may have a cardinality smaller than the number of TRPs—the UE can still benefit from determining beam pairs for all candidate TRPs / APs. This is because the more TRPs used, the more reliable the communication between the network and the UE is improved. In fact, current NR specifications include a time-division multiplexing (TDM) repetition scheme for all DL and UL channels on two different TRPs, which has already shown improved reliability compared to single TRP repetition due to improved spatial diversity.

[0123] refer to Figure 7This is a sequence diagram illustrating a method for determining one or more transmit beams, which will be used for communication between a wireless device 120 (or UE) and at least one network node 110 (e.g., a TRP or AP or a node controlling one of these) in a wireless network. From the perspective of the wireless device 120, Figure 7 A method is provided for facilitating the determination of one or more transmit beams to be used by wireless device 120 for communication with network node 110. From the perspective of network node 110, Figure 7 A method is provided for determining one or more transmit beams to be used by a wireless device 120 for communicating with the wireless device 120; additionally, a network node 110 may determine one or more beams for its own use in the communication. Preferably, the wireless device 120 is a wireless device having simulated beamforming.

[0124] In the first of method 700 Step 710 In this process, wireless device 120 indicates "special uplink beam management capability" to network node 110, which involves implicit drop rules, meaning that the wireless device supports and applies implicit drop rules. Step 710 may not be necessary in method 700 if implemented in a technical context where applicable specifications imply that all served wireless devices 120 must support implicit drop rules.

[0125] In some embodiments, “special uplink beam management capabilities” (which may have different names) include one or more of the following:

[0126] 1. Wireless devices support implicit dropping of UL RS resources in triggered UL RS resource sets that have been configured for UL beam management;

[0127] 2. The wireless device supports the indication of implicitly dropping the UL RS port of the UL RS resource in the triggered UL RS resource set that has been configured for UL beam management;

[0128] 3. The number of panels 126 of the wireless device, each panel 126 representing a set of associated antennas;

[0129] 4. The number of beam types supported by each panel 126, with each beam type associated with a different beamwidth;

[0130] 5. Approximate beamwidth of the supported beam types;

[0131] 6. The number of supported beams for the supported beam type;

[0132] 7. The number of beams supported for panel 126;

[0133] 8. The supported beam types and the number of supported beams for panel 126;

[0134] 9. The number of narrow beams supported for panel 126;

[0135] 10. The number of ports supported for panel 126;

[0136] 11. The number or identifier of those panels 126 that can be emitted simultaneously;

[0137] 12. The number of available emission chains for panel 126.

[0138] Regarding items 8-9, the number of supported beams for a given type refers to the number of unique transmit beams of that type that the wireless device 120 wishes to evaluate. The wireless device 120 may indicate in its special beam scanning capability the number of beams of that type it can support, or fewer. In a different manner, the number of supported beams in the special beam scanning capability does not need to be a technically exhaustive description of the wireless device 120's hardware or software, but rather refers to the number of beams that the wireless device 120 wishes to evaluate with network assistance. The number of supported beams indicated in the special uplink beam management capability can be understood as the preferred number of beams.

[0139] For example, information from Project 11 can be used by network node 110 to provide a UL RS configuration that includes a set of UL RS resources for UL beam management configurations as many as the panels capable of transmitting simultaneously.

[0140] In the optional second Step 712 In this process, which may be part of method 700 together with or separately from step 710, the wireless device 120 indicates to the network node 110 an association between at least one of its panels 126 and the TRP / AP 115. This association may be used when the wireless device 120 deems it necessary, for example, to indicate that a particular panel 126 currently has a favorable orientation relative to the TRP / AP 115. Furthermore, according to some embodiments, it is understood that if the wireless device 120 indicates two such associations—one between the first panel 126 and the first TRP / AP 115, and another between the second panel 126 and the second TRP / AP 115—the wireless device 120 should support simultaneous beam scanning on the first and second panels 26, i.e., the UL RS resources for these first and second panels 126 may partially overlap in time.

[0141] It should be understood that step 712 is typically performed in advance. For example, the indication 712 of the association between panel 126 and TRP / AP 115 is performed in a different beam management process than the transmission to be performed on the UL RS resource (see step 718 below). Alternatively, indication 712 and measurement 718 are two instantiations of the same type of beam management process.

[0142] Method 700 includes Step 714 The network node 110 transmits—and the wireless device 120 receives—a UL RS configuration containing UL RS resources grouped into multiple UL RS resource sets. Functionally, the UL RS configuration indicates multiple UL RS resources forming several groups (UL RS resource sets). The fact that a group of UL RS resources belongs to a specific UL RS resource set can be identifiable because they carry UL RS resource set indices with equal values ​​and / or they occupy certain positions in the data structure representing the UL RS configuration. UL RS resource sets may all have an equal number of UL RS resources, or the number may vary across UL RS resource sets. UL RS resource sets may all have an equal number of UL RS ports, or the number of ports may vary across UL RS resource sets.

[0143] UL RS configuration can be sent from TRP 115a to wireless device 120. UL RS configuration can be transmitted using semi-static signaling, such as RRC signaling.

[0144] UL RS resources can correspond to probe reference signal (SRS) resources. A set of UL RS resources can consist of UL RS resources used for non-periodic transmission relative to the time domain; possible alternatives include semi-persistent or periodic transmissions.

[0145] In the 3GPP NR implementation, the optional purpose is beamManagement, which indicates the evaluation of different UE beams used to simulate beamforming arrays. An equivalent purpose can be indicated in the 6G implementation of method 700.

[0146] Method 700 also includes Step 716 The wireless device 120 receives an activation trigger from the network node 110. The activation trigger indicates at least one UL RS resource set from the configured UL RS resource set. (The activation trigger can be considered associated with one or more UL RS resource sets.) The activation trigger can be transmitted in downlink control information (DCI), in MAC layer control elements (MAC-CE), or via RRC signaling. In a 6G implementation, another suitable signal carrier may be relied upon.

[0147] In some embodiments, activation triggering includes an indication of the beam type used by the wireless device for transmission over UL RS resources in the indicated UL RS resource set. The indicated beam type may have been selected from a plurality of predefined beam types, each having two or more unique beamwidths relative to the others. Additionally or alternatively, activation triggering may include an indication of the number of UL RS resources in the indicated UL RS resource set to be used for transmission.

[0148] In another embodiment, activation triggering includes the number of UL RS resources to be emitted on the indicated UL RS resource set.

[0149] In another embodiment, the activation trigger includes the identifier of one or more UL RS resources to be transmitted on the indicated UL RS resource set. From a signaling perspective, equivalently and possibly more economically, the activation trigger may include the identifier of one or more UL RS resources to be discarded. In either case, the implicit discard rule simply specifies that the content of the activation trigger will be observed.

[0150] After the wireless device 120 has received the activation trigger, Step 718 In this process, it transmits on multiple UL RS resources within one or more indicated UL RS resource sets. (Using language closer to some paragraphs of 3GPP TS 38.214, it can be said that the wireless device 120 transmits the multiple UL RS resources.) Simultaneously, the network node 110 performs measurements on the transmitted UL RS resources. This measurement can be an SRS measurement according to the 3GPP NR specification or according to the 6G specification.

[0151] Step 718 includes Sub-step 718.1The network node 110 evaluates the indicated UL RS resource set(s) based on a pre-agreed implicit discard rule depending on the characteristics of the wireless device, and decides to omit transmissions on at least one of the UL RS resources(s)(s). Omitting transmissions on UL RS resources(s) ...

[0152] In the next Step 720 In step 718, based on the measurements, network node 110 can select one or more of the most suitable transmit beams for use by wireless device 120. Network node 110 can select one or more transmit beams from first panel 126 and one or more transmit beams from second panel 126. The transmit beams can be identified based on UL RS resources, typically UL RS resources where network node 110 receives UL RS with the highest signal energy or the highest signal-to-interference-and-noise ratio (SINR).

[0153] exist Step 722 In this process, one or more selected beams are then used for communication by uplink transmission of data and signaling from network node 110 and wireless device 120. Step 722 may optionally include simultaneous downlink reception and / or simultaneous uplink transmission from multiple UE panels 126.

[0154] We will now discuss some specific embodiments and further developments of the basic method 700 described above.

[0155] In one embodiment, all UL RS resource sets configured for UL beam management in the UL RS resource configuration have an equal number of UL RS resources. The specific uplink beam management capability (indicated in step 710) includes the number of supported beams for at least two panels 126, and the UL RS resource sets configured for UL beam management in the UL RS resource configuration include as many UL RS resources as the maximum number of supported beams for the panels. Through the action of implicit drop rules, the UL RS resources corresponding to the panel(s) that do not support the full number of beams are dropped. In particular, the maximum number of supported beams for the panel can be the maximum value among all beam types, typically the number of beams with the minimum width.

[0156] In one embodiment, at least two UL RS resource sets in the UL RS resource configuration have different numbers of UL RS resources, and the indicated specific uplink beam management capability includes identifiers of panels capable of simultaneous transmission and the number of supported beams for each of these panels. Network node 110 can then define a UL RS resource configuration with n UL RS resource sets for use by an n-tuple of simultaneously transmitting panels, with the first to nth UL RS resource sets having a corresponding number of UL RS resources corresponding to the maximum number of supported beams for the subgroup of panels. This embodiment may include a similar optimization process where the panels 126 of wireless device 120 are intentionally categorized as “small,” “medium,” “large,” and “very large” panels with respect to the number of beams they support. This method can also be applied to each supported beam type. As a result, the same UL RS resource sets (four in this example) can be reused. A similar optimization process can further attempt to minimize the number of dropped resources. As a result, although implicit drop rules will be active, the number of dropped UL RS resources remains low or even minimal.

[0157] Continuing with the example in Table 1, the following input data is provided.

[0158] Panel 1, beamwidth A1 beams

[0159] Panel 1, beamwidth B5 beams

[0160] Panel 1, beamwidth C9 beams

[0161] Panel 2, beamwidth A1 beams

[0162] Panel 2, beamwidth B4 beams

[0163] Panel 2, beamwidth C12 beams

[0164] Panel 3, beamwidth A1 beams

[0165] Panel 3, beamwidth B4 beams

[0166] Panel 3, beamwidth C10 beams

[0167] The following UL RS configuration can be achieved under this embodiment.

[0168] UL RS resource set S11 beams

[0169] UL RS resource set S25 beams

[0170] UL RS resource set S312 beams

[0171] Among them, n = 3 can be identified. If UL RS resource sets S1, S2 and S3 are used for beamwidths A, B and C for all panels respectively, then no UL RS resources will be discarded in UL RS resource set S1, at most one (=5-4) UL RS resources will be discarded in UL RS resource set S2, and at most three (=12-9) UL RS resources will be discarded in UL RS resource set S3.

[0172] Another embodiment addresses a case where the specific uplink beam management capability includes the number of supported ports for at least two panels. Then, all UL RS resource sets configured for UL beam management in the UL RS resource configuration can be assigned an equal number of UL RS ports, and the UL RS resource sets configured for UL beam management in the UL RS resource configuration have as many UL RS ports as the maximum number of supported ports. When the specific uplink beam management capability includes the number of available transmit chains for at least two panels, all UL RS resource sets configured for UL beam management in the UL RS resource configuration can be assigned an equal number of UL RS ports, and the UL RS resource sets configured for UL beam management in the UL RS resource configuration can have as many UL RS ports as the maximum number of available transmit chains for said at least two panels. In each case, an implicit drop rule will ensure that those UL RS resources exceeding the maximum number of supported ports and the maximum number of transmit chains, respectively, are dropped.

[0173] The implicit drop rule can be defined differently in different embodiments of method 700. For example, the implicit drop rule can specify that any UL RS resource in the UL RS resource set that exceeds the number of beams supported by the panel associated with the UL RS resource set (as indicated in step 712) should be dropped (as indicated in step 710). Specifically, the implicit drop rule can specify that all such excessive UL RS resources should be dropped.

[0174] When this teaching is applied to the UL RS resource set including Each UL RS resource and its specific uplink beam management capability indicates the panel associated with the UL RS resource set that supports the type of beam to be used. In the case of a single beam, the implicit drop-off rule stipulates that the number of UL RS resources that should be dropped in the UL RS resource set is equal to the difference. The beam type to be used can have a specific width, such as narrow, half-width, or wide, and the beam type can be transmitted during activation triggering (step 716).

[0175] In another embodiment, where the association between the TRP / AP and the panel of the wireless device has been indicated, an implicit drop rule stipulates that any UL RS port in the UL RS resource set exceeding the number of ports supported by the panel associated with the UL RS resource set should be dropped. Alternatively or additionally, the implicit drop rule may stipulate that any UL RS port in the UL RS resource set exceeding the number of transmit chains available for said panel should be dropped. In some implementations, transmit chains correspond to ports such that the number of supported ports equals the number of available transmit chains.

[0176] In one example applying the teachings of this embodiment, the UL RS resource set includes having Each port's UL RS resources, special uplink beam management capabilities, and panel support associated with the UL RS resource set. Ports (and / or One launch chain can be used for this panel), and the implicit discard rule stipulates that UL resource centralization has ULRS resources for a given port should be discarded. To express this differently, knowing that one ULRS resource can specify one port and two or more ULRS resources can specify the same port, this example specifies that the set of ULRS resources before discarding includes those specifying a total of... A unique port of UL RS resources, and the total number of UL RS resources to be discarded are specified together. A unique port. Under one option, the implicit discard rule specifies which ports should be discarded. A ULRS resource is one of those ULRS resources with the lowest port index. Alternatively, an implicit discard rule specifies which ULRS resources should be discarded. Each UL RS resource is one of those UL RS resources with the highest port index.

[0177] In some embodiments, an implicit drop rule may specify that any UL RS resource in the indicated UL RS resource set exceeding the number of beams of the indicated beam type supported by the panel used by wireless device 120 for transmission on the UL RS resource set should be dropped. What the wireless device will use is likely known to network node 110. In one example, the activation trigger sent in step 716 may include an indication of the beam type to be used by the wireless device for transmission on UL RS resources(s) in the indicated UL RS resource set. In another example, the beam type may be inferred from the current operating state or similar conditions, or only a single beam type may exist for wireless device 120 to select from. Furthermore, what the network node 110 will use for which UL RS resource set, and this knowledge allows network node 110 to predict which UL RS resources to drop, i.e., which UL RS resources wireless device 120 will omit for transmission.

[0178] In such an embodiment of method 700 (where the activation trigger includes an indication of the number of UL RS resources to be emitted on the indicated UL RS resource set), an implicit drop rule may specify that any UL RS resource exceeding the indicated number of UL RS resources in the indicated UL RS resource set should be dropped. Specifically, the implicit drop rule may specify that if the indicated UL RS resource set includes... A set of UL RS resources, and activation triggers include the transmission to be performed on the indicated UL RS resource set. The indication of a UL RS resource, then the UL RS resource set One UL RS resource will be discarded. Quantity It can be equal to the number of beams supported by the associated panel 126.

[0179] Furthermore, in these embodiments, the implicit discard rule can also specify which UL RS resources in the UL RS resource set will be discarded. Some envisioned options are:

[0180] - UL RS resources that should be discarded are those that are the first in the indicated UL RS resource focus time;

[0181] - UL RS resources that should be discarded are those that are the last in the indicated UL RS resource timeframe;

[0182] - The UL RS resources that should be discarded have the lowest UL RS resource index in the indicated UL RS resource set;

[0183] - UL RS resources that should be discarded have the highest UL RS resource index in the indicated UL RS information set.

[0184] In some embodiments of method 700, step 718 includes another Sub-step 718.2 In this embodiment, wireless device 120 sends an indication to network node 110 of at least one UL RS resource, on which the wireless device will omit transmission. Due to this advance indication, the network is free to reallocate the indicated UL RS resource to different wireless devices (not shown) served by the network, which can contribute to efficient use of the UL RS resource at the system level. Even if the indicated UL RS resource is not reallocated to a different wireless device, network node 110 itself can benefit from indication 718.2 by saving measurement effort (e.g., activation of the receiver circuitry) on the UL RS resource in question.

[0185] Summarizing this disclosure in general terms, numerous standard enhancements for UL beam management have been described for UEs equipped with different types of UE panels. In a first instance, the UE signals to the gNB enhanced information associated with the attributes of its antenna panel, such as the number of panels, the beams of each panel, etc. The gNB then uses said information to configure a suitable set of UL RS resources parameterized for the UE. Next, the gNB triggers the UE to transmit the configured UL RS resources. The UE then transmits the triggered UL RS resources (from different panels / beams) and discards one or more of the triggered UL RS resources. For panels supporting fewer beams than the number of configured UL RS resources, discarding may occur.

[0186] The aspects of this disclosure have been described above primarily with reference to some embodiments. However, as will be readily understood by those skilled in the art, other embodiments besides those disclosed above may also be within the scope of the invention as defined by the appended claims.

Claims

1. A method (700) implemented in a wireless device (120) for facilitating the determination of at least one transmit beam to be used in association with a transmit / receive point TRP (115) or access point AP in a wireless network (110), the method comprising: Receive (714) from the network a UL RS configuration that is grouped into multiple uplink reference signal UL RS resource sets; Receive (716) an activation trigger from the network, the activation trigger indicating at least one UL RS resource set from the configured UL RS resource set; Transmission is performed on multiple UL RS resources within one or more indicated UL RS resource sets (718); and Receive (722) instructions from the network for communicating with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. The method further includes: evaluating (718.1) a pre-agreed implicit drop rule for one or more indicated UL RS resource sets, depending on the characteristics of the wireless device, and deciding to omit transmissions on at least one of the UL RS resources therein.

2. The method of claim 1, further comprising: Indicate to the network the special uplink beam management capability involving the implicit drop rule (710).

3. The method as described in claim 1 or 2, wherein, Omitting a transmission on a UL RS resource corresponds to transmitting at a maximum of 10% of the nominal transmission energy, preferably transmitting at zero energy, and more preferably abandoning the transmission altogether.

4. The method as described in any of the preceding claims, further comprising: Send to the network an indication that the wireless device will omit at least one UL RS resource transmitted thereon (718.2).

5. The method as described in any one of the preceding claims, further comprising: The network is instructed (712) to associate the TRP / AP with the panels of the wireless device, each panel representing a set of antennas.

6. A method (700) implemented in a network node of a wireless network (110) for facilitating the determination of at least one transmit beam to be used by a wireless device (120) in association with a transmit / receive point TRP (115) or an access point AP in the wireless network, the method comprising: Send (714) a UL RS configuration that is grouped into multiple uplink reference signal UL RS resource sets to the wireless device; Send an activation trigger (716) to the wireless device, the activation trigger indicating at least one UL RS resource set from the configured UL RS resource set; Perform (718) measurements on multiple UL RS resources in one or more indicated UL RS resource sets; Select (720) one or more of the UL RS resources on which measurements have already been performed; and Send (722) instructions to the wireless device for communicating with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. Measurements on at least one UL RS resource in one or more indicated UL RS resource sets are omitted according to a pre-agreed implicit discard rule that depends on the characteristics of the wireless device.

7. The method of claim 6, further comprising: Instructions are obtained regarding the specific uplink beam management capabilities (710) related to the implicit drop rules.

8. The method of claim 6 or 7, further comprising: The wireless device receives an indication (718.2) that it will omit at least one UL RS resource transmitted thereon, and omits the measurement on the at least one UL RS resource.

9. The method of any one of claims 6 to 8, further comprising: Indication (712) is obtained between the TRP / AP and the panels of the wireless device, each panel representing a set of antennas.

10. The method of claim 2 or 7, wherein, The special uplink beam management capability (710) includes one or more of the following: The wireless device supports an indication of implicit discarding of UL RS resources in a triggered UL RS resource set that has been configured for UL beam management. The wireless device supports an indication for implicit discarding of UL RS ports of UL RS resources in a triggered UL RS resource set that has been configured for UL beam management. The number of panels in the wireless device, where each panel represents a set of associated antennas; The number of beam types supported by each panel, with each beam type associated with a different beamwidth; Approximate beamwidth of supported beam types; The number of supported beams for the supported beam type; The number of beams supported by the panel; This refers to the type of beams supported and the number of beams supported by the panel. The number of narrow beams supported for the panel; The number of ports supported by the panel; The number or identifier of those panels that can be launched simultaneously; The number of available emission chains for the panel.

11. The method of claim 10, wherein: The specific uplink beam management capability (710) includes the number or identifier of those panels that can be transmitted simultaneously, each panel representing a set of associated antennas; and The UL RS configuration includes a set of UL RS resources for UL beam management configurations, as many as the panels capable of simultaneous transmission.

12. The method as described in any of the preceding claims, wherein, In the UL RS resource configuration, all UL RS resource sets configured for UL beam management have an equal number of UL RS resources.

13. The method of claim 12, as referred to in claim 2 or 7, wherein: The special uplink beam management capability (710) includes the number of supported beams for at least two panels, each panel representing a set of associated antennas; as well as The UL RS resource set configured for UL beam management in the UL RS resource configuration includes as many UL RS resources as the maximum number of supported beams for the panel.

14. The method according to any one of claims 1 to 11, wherein, At least two ULRS resource sets in the UL RS resource configuration have a different number of UL RS resources.

15. The method as described in claim 14, as cited in claim 2 or 7, The special uplink beam management capability (710) includes: Identifiers of the panels that can transmit simultaneously, each panel representing a set of associated antennas, and the number of supported beams for each of these panels; The UL RS resource configuration consists of n UL RS resource sets for use by n-tuples of simultaneously transmitting panels; and The first to nth UL RS resource sets have a corresponding number of UL RS resources corresponding to the maximum number of supported beams in the subgroup of the panel.

16. The method as described in any of the preceding claims, wherein, In the UL RS resource configuration, all UL RS resource sets configured for UL beam management have an equal number of UL RS ports.

17. The method of claim 16 as referred to in claim 2 or 7, wherein... The special uplink beam management capability (710) includes the number of supported ports for at least two panels and / or the number of available transmit chains for at least two panels, each panel representing a set of associated antennas; and The UL RS resource set configured for UL beam management in the UL RS resource configuration has as many UL RS ports as the maximum number of supported ports and / or the maximum number of available transmit chains for the at least two panels.

18. The method as described in any of the preceding claims, including claim 5 or 9, wherein, The implicit discard rule states that any UL RS resource in the UL RS resource set that exceeds the number of beams supported by the panel associated with the UL RS resource set should be discarded.

19. The method of claim 18 as referred to by claim 2 or 7, wherein: The UL RS resource set includes One UL RS resource; The special uplink beam management capability (710) indicates the type of beam to be used by the panel associated with the UL RS resource set. One beam; and The implicit discard rule specifies that, in the UL RS resource set Each UL RS resource should be discarded.

20. The method of claim 19, wherein, The beam type to be used corresponds to a narrow beam.

21. The method as described in any of the preceding claims, including claim 5 or 9, wherein, The implicit discard rule stipulates that any UL RS port in the UL RS resource set that exceeds the number of ports supported by the panel associated with the UL RS resource set should be discarded, and / or any UL RS port in the UL RS resource set that exceeds the number of transmit chains available for the panel should be discarded.

22. The method as described in claim 21 of claims 2 and 5 or 7 and 9, wherein: The UL RS resource set includes having UL RS resources for each port; The special uplink beam management capability (710) indicates panel support associated with the UL RS resource set. One port, and / or A single emission chain is available for the panel; as well as The implicit discard rule stipulates that, in the UL resource set, there are The UL RS resources for each port should be discarded.

23. The method of claim 22, wherein, The implicit discard rule specifies that the items that should be discarded... The UL RS resources are those UL RS resources with the lowest port index, or those that, according to the implicit discard rule, should be discarded. Each UL RS resource is one of those UL RS resources with the highest port index.

24. The method as described in any of the preceding claims, wherein, The activation trigger is transmitted in the downlink control information (DCI).

25. The method as described in any of the preceding claims, wherein, The activation trigger includes an indication of the beam type to be used by the wireless device for transmission on the UL RS resources in the indicated UL RS resource set, wherein, optionally, the beam type is selected from a variety of beam types with different beamwidths.

26. The method of claim 25, wherein, The implicit discard rule states that any UL RS resource in the indicated UL RS resource set that exceeds the number of beams of the indicated beam type supported by the panel used by the wireless device for transmission on the indicated UL RS resource set should be discarded.

27. The method of claim 25, as cited in claim 19, wherein, The beam type to be used is the beam type indicated in the activation trigger.

28. The method as described in any of the preceding claims, wherein, The activation trigger includes an indication of the number of UL RS resources to be emitted on the indicated UL RS resource set.

29. The method of claim 28, wherein, The implicit discard rule states that any UL RS resource exceeding the indicated number of UL RS resources in the indicated UL RS resource set should be discarded.

30. The method of claim 28 or 29, wherein: The indicated UL RS resource set includes One UL RS resource; The activation trigger includes the emission to be carried out on the indicated UL RS resource set. Indication of UL RS resources; and The implicit discard rule specifies that, in the UL RS resource set Each UL RS resource should be discarded.

31. The method of claim 19, 20, 26 or 29, wherein, The implicit discard rule specifies that the UL RS resource to be discarded is either the first in time or the last in time of the indicated UL RS resource cluster.

32. The method of claim 19, 20, 26 or 29, wherein, The implicit discard rule specifies that the UL RS resource to be discarded has the lowest or highest UL RS resource index in the indicated UL RS resource set.

33. The method as described in any of the preceding claims, wherein, The activation trigger includes the identifier of one or more UL RS resources to be emitted on the indicated UL RS resource set.

34. The method as described in any of the preceding claims, wherein, The UL RS resources consist of UL RS resources used for non-periodic transmission.

35. The method as described in any of the preceding claims, wherein, The UL RS resource corresponds to the detection reference signal SRS resource.

36. A wireless device (120) for facilitating the determination of at least one transmit beam to be used in association with a transmit / receive point TRP (115) or access point AP in a wireless network (110), the wireless device including processing circuitry (122) configured to: Receive UL RS configuration from the network, which is grouped into multiple uplink reference signal UL RS resource sets; Receive an activation trigger from the network, the activation trigger indicating at least one UL RS resource set from the configured UL RS resource set; Transmission is performed on multiple UL RS resources within one or more indicated UL RS resource sets; and Receive instructions from the network for communicating with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. in, The processing circuitry is further configured to: evaluate, for one or more indicated UL RS resource sets, a pre-agreed implicit drop rule depending on the characteristics of the wireless device, and determine to omit transmissions on at least one of the UL RS resources therein.

37. A network node of a wireless network (110) for facilitating the determination of at least one transmit beam to be used by a wireless device (120) in association with a transmit / receive point TRP (115) or access point AP in the wireless network, the network node including processing circuitry (112) configured to: Send the UL RS configuration, which is grouped into multiple uplink reference signal UL RS resource sets, to the wireless device; Send an activation trigger to the wireless device, the activation trigger indicating at least one UL RS resource set from the configured UL RS resource set; Perform measurements on multiple UL RS resources within one or more indicated UL RS resource sets; Select one or more of the UL RS resources on which measurements have already been performed; and The wireless device is sent instructions to communicate with the network using at least one transmit beam, each transmit beam corresponding to one of the transmitted UL RS resources. in, Measurements on at least one of the UL RS resources in one or more indicated UL RS resource sets are omitted according to a pre-agreed implicit discard rule that depends on the characteristics of the wireless device.

38. A computer program (124) comprising instructions which, when executed on a processing circuit (122) of a wireless device (120), cause the wireless device to perform the method (700) as claimed in any one of claims 1 to 5 and 10 to 35.

39. A computer program (114) comprising instructions which, when executed on a processing circuit (112) of a network node, cause the network node to perform the method (700) as claimed in any one of claims 6 to 35.

40. A computer program product comprising the computer program (114, 124) as described in claim 38 or 39 and a computer-readable storage medium thereon storing the computer program.

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