Techniques for indicating a preferred beam in a multi-transmission and reception point (multi-trp) system based on a default operating frequency (DOF) mismatch

Abstract

The present disclosure provides systems, methods, and apparatuses for selection of one or more transmission and reception points (TRPs) within a multi-TRP system. In one aspect, a user equipment (UE) can transmit an indication of a selected TRP and an indication of one or more beams that the selected TRP can use to communicate with the UE based on a mismatch between a default operating frequency (DOF) of each TRP within the multi-TRP system and a DOF of the UE. For example, the UE can receive an indication of a DOF for each antenna port of a TRP within the multi-TRP system, and the UE can compare the indicated DOF to a DOF of each antenna module of the UE. The UE can select a TRP to communicate with and select one or more ports that the selected TRP can use to communicate with the UE based on the comparison.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] The present Application for Patent claims the benefit of U.S. Patent Application No. 17 / 104,435 by Raghavan et al., entitled “TECHNIQUES FOR INDICATING PREFERRED BEAMS IN MULTI-TRANSMISSION AND RECEPTION POINT (MULTI-TRP) SYSTEMS BASED ON DEFAULT OPERATING FREQUENCY (DOF) MISMATCH,” filed November 25, 2020, assigned to the assignee hereof and expressly incorporated by reference herein in its entirety. TECHNICAL FIELD

[0003] The following relates to wireless communications, including techniques for indicating beams in multi-transmission and reception point (multi-TRP) systems based on default operating frequency (DOF) mismatch. BACKGROUND

[0004] Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems can be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power). Examples of such multiple- access systems include fourth generation (4G) systems (e.g., Long Term Evolution (LTE) systems, LTE-Advanced (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems, which can be referred to as New Radio (NR) systems. These systems can employ technologies such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal frequency division multiple access (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple-access communications system can include one or more base stations or one or more network access nodes, each simultaneously supporting communication for multiple communication devices, which can be otherwise known as user equipment (UE).

[0005] In some wireless communications systems, a UE can communicate with multiple transmission and reception points (TRPs) in a multi-TRP deployment. The UE can communicate with the multiple TRPs in accordance with beamforming techniques by which the UE and the multiple TRPs communicate with one another via one or more directional beams. SUMMARY

[0006] The systems, methods, and devices of the present disclosure each have several innovative aspects, no single one of which is solely responsible for the desirability of the present disclosure.

[0007] One innovative aspect of the subject matter described in this disclosure can be implemented in a method for wireless communication at a user equipment (UE). The method can include receiving a control message that indicates a first set of default operation frequencies (DOFs) for a first set of ports associated with a first transmission and reception point (TRP) and a second set of DOFs for a second set of ports associated with a second TRP, and transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0008] Another innovative aspect of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication at a UE. The apparatus can include a first interface, a second interface, and a processing system. The first interface can be configured to obtain a control message that indicates a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP. The first interface or the second interface can also be configured to output or obtain beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0009] Another innovative aspect of the subject matter described in this disclosure can be implemented in another apparatus for wireless communication at a UE. The apparatus can include a processor, a memory coupled with the processor, and instructions stored in the memory. The instructions can be executable by the processor to cause the apparatus to receive a control message that indicates a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP, and transmit or receive beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0010] Another innovative aspect of the subject matter described in this disclosure can be implemented in another apparatus for wireless communication at a UE. The apparatus can include means for receiving a control message indicating a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP; and means for transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0011] Another innovative aspect of the subject matter described in this disclosure can be implemented in a non-transitory computer-readable medium storing code for wireless communication at a UE. The code can include instructions executable by a processor to receive a control message indicating a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP; and transmit or receive beam selection signaling based on the control message, where the beam selection signaling indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0012] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving an indication of a first mismatch between a first DOF associated with the first port and a DOF of the UE and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within a threshold mismatch.

[0013] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving an indication of a first mismatch between a first DOF associated with the first port and a DOF of the UE and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within a threshold mismatch.

[0014] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving the beam selection signaling indicating a pair of receive beams of the UE for receiving a multi-TRP transmission from the first TRP and the second TRP.

[0015] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for receiving the multi-TRP transmission from the first TRP and the second TRP via the pair of receive beams of the UE.

[0016] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, receiving the multi-TRP transmission from the first TRP and the second TRP can include operations, features, means, or instructions for receiving the multi-TRP transmission from the first TRP via at least the first beam on a first frequency band and from the second TRP via at least the second beam on a second frequency band, where the first frequency band and the second frequency band include an ultra-wideband frequency band.

[0017] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving the beam selection signaling indicating a pair of transmit beams of the UE for transmitting a multi-TRP transmission to the first TRP and the second TRP.

[0018] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for transmitting the multi-TRP transmission to the first TRP via a first transmit beam of the pair of transmit beams and to the second TRP via a second transmit beam of the pair of transmit beams.

[0019] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for receiving, from the first TRP via a first one or more ports of the first set of ports, a first one or more downlink reference signals and receiving, from the second TRP via a second one or more ports of the second set of ports, a second one or more downlink reference signals, where the beam selection signaling can be based on the first one or more downlink reference signals and the second one or more downlink reference signals.

[0020] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for transmitting, to the first TRP, a first one or more uplink reference signals and transmitting, to the second TRP, a second one or more uplink reference signals, where the beam selection signaling can be based on the first one or more uplink reference signals and the second one or more uplink reference signals.

[0021] In some implementations, as implemented in the methods, apparatuses, and non- transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emission.

[0022] One innovative aspect of the subject matter described in this disclosure can be implemented in a method for wireless communications at a first TRP. The method can include transmitting, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP, and transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0023] Another innovative aspect of the subject matter described in this disclosure can be implemented in an apparatus for wireless communication at a first TRP. The apparatus can include a first interface, a second interface, and a processing system. The first interface can be configured to transmit, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP. The first interface or the second interface can also be configured to transmit or receive, based on the control message, beam selection signaling indicating a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0024] Another innovative aspect of the subject matter described in this disclosure can be implemented in another apparatus for wireless communication at a first TRP. The apparatus can include a processor, a memory coupled with the processor, and instructions stored in the memory. The instructions can be executable by the processor to cause the apparatus to transmit, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP, and transmit or receive, based on the control message, beam selection signaling indicating a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0025] Another innovative aspect of the subject matter described in this disclosure can be implemented in another apparatus for wireless communication at a first TRP. The apparatus can include means for transmitting, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP, and means for transmitting or receiving, based on the control message, beam selection signaling indicating a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0026] Another innovative aspect of the subject matter described in this disclosure can be implemented in a non-transitory computer-readable medium storing code for wireless communication at a first TRP. The code can include instructions executable by a processor to transmit, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP, and transmit or receive beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0027] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based on a first mismatch between a DOF associated with the first port and a DOF of the UE being within a threshold mismatch and a second mismatch between a DOF associated with the second port and the DOF of the UE being within the threshold mismatch.

[0028] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving an indication of a first mismatch between a DOF associated with the first port and a DOF of the UE and a second mismatch between a DOF associated with the second port and the DOF of the UE.

[0029] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving the beam selection signaling indicating a pair of receive beams of the UE for receiving a multi-TRP transmission from the first TRP and the second TRP.

[0030] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for outputting, jointly with the second TRP, the multi-TRP transmission to the UE via a receive beam of the pair of receive beams at the UE using at least the first beam associated with the first port.

[0031] In some implementations, as implemented in the methods, apparatuses, and non- transitory computer-readable media described herein, transmitting the multi-TRP transmission to the UE can include operations, features, means, or instructions for transmitting the multi-TRP transmission on a first frequency band, the first frequency band being different from a second frequency band on which the second TRP transmits the multi-TRP transmission, wherein the first frequency band and the second frequency band comprise a super wideband frequency band.

[0032] In some implementations, as implemented in the methods, apparatuses, and non- transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving the beam selection signaling indicating a pair of transmit beams of the UE for transmitting multi-TRP transmissions to the first TRP and the second TRP.

[0033] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for receiving, from the UE, the multi-TRP transmission via a transmit beam of the pair of transmit beams of the UE using at least the first beam associated with the first port.

[0034] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for transmitting one or more downlink reference signals via one or more ports of the first set of ports, wherein the beam selection signaling can be based on the one or more downlink reference signals.

[0035] In some implementations, the methods, apparatuses, and non-transitory computer- readable media described herein can further include operations, features, means, or instructions for receiving one or more uplink reference signals from the UE at one or more ports of the first set of ports, wherein the beam selection signaling can be based on the one or more uplink reference signals.

[0036] In some implementations, as embodied in the methods, apparatuses, and non-transitory computer-readable media described herein, transmitting or receiving the beam selection signaling can include operations, features, means, or instructions for transmitting or receiving the indication of the first beam associated with the first port and the second beam associated with the second port based on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold on out-of-band emission.

[0037] Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims. Note that the relative dimensions of the following figures can not be drawn to scale. BRIEF DESCRIPTION OF DRAWINGS

[0038] Figure 1 AND Figure 2 An example of a wireless communications system that supports techniques for indicating beams in a multi-transmit and receive point (multi-TRP) system based on default operational frequency (DOF) mismatch is shown.

[0039] Figure 3 An example of a beam selection diagram that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown.

[0040] Figure 4 An example of a process flow that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown.

[0041] Figure 5 AND Figure 6 A block diagram of an example device that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown.

[0042] Figure 7 AND Figure 8 A flow diagram illustrating a method that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown.

[0043] Like reference numbers and designations in the various drawings indicate like elements. DETAILED DESCRIPTION

[0044] For the purpose of describing the innovative aspects of this disclosure, the following description relates to certain implementations. However, those skilled in the art will readily recognize that the teachings herein can be applied in a variety of different ways. The described implementations can be implemented in any device, system, or network capable of transmitting and receiving radio frequency signals according to any one of the Institute of Electrical and Electronics Engineers (IEEE) 16.11 standards or any of the following: IEEE 802.11 standard, Standard, Code Division Multiple Access (CDMA), Frequency Division Multiple Access (FDMA), Time Division Multiple Access (TDMA), Global System for Mobile Communications (GSM), GSM or General Packet Radio Service (GPRS), Enhanced Data GSM Environment (EDGE), Terrestrial Trunking Radio (TETRA), Wideband-CDMA (W-CDMA), Evolved Data Optimized (EV-DO), 1xEV-DO, EV-DO Rev A, EV-DO Rev B, High-Speed ​​Packet Access (HSPA), High-Speed ​​Downlink Packet Access (HSDPA), High-Speed ​​Uplink Packet Access (HSUPA), Evolved High-Speed ​​Packet Access (HSPA+), Long Term Evolution (LTE), AMPS, or other known signals used for communication in wireless, cellular, or Internet of Things (IoT) networks (e.g., systems utilizing 3G, 4G, or 5G, or other implementations or technologies thereof).

[0045] In some wireless communication systems, a UE can communicate with multiple TRPs in a multiple transmit and receive point (TRP) deployment. For example, a UE can communicate with at least two TRPs, including a first TRP and a second TRP, based on multi-TRP communication techniques. In some examples, the UE can communicate with the first and second TRPs on various radio frequency spectrum bands supporting ultra-wideband operation, such as FR2 (which may include frequencies between 24.25–52.6 GHz) or FR4 (which may include frequencies between 52.6 GHz–114.25 GHz) radio frequency spectrum bands. In such examples, the UE, the first TRP, or the second TRP can tune the radio frequency chain of their respective antenna subarrays, panels, ports, or modules to a default operating frequency (DOF). For example, the UE, the first TRP, or the second TRP can tune or optimize a corresponding analog or radio frequency beamforming codebook for a carrier frequency within the ultra-wideband (on which the UE, the first TRP, and the second TRP can communicate). Such a carrier frequency may be referred to herein as the DOF (the frequency to which the antenna array is tuned or optimized relative to other frequencies within the ultra-wideband). In addition, each of the UE, the first TRP, and the second TRP can configure multiple antenna ports, antenna modules, or antenna elements at the corresponding device with different DOFs, so that each device can support different DOFs at different antenna ports, antenna modules, or antenna elements.

[0046] In some implementations of the disclosure, a UE can select to communicate with one or both of a first TRP or a second TRP and can indicate a set of beams that the first TRP or the second TRP, or both, can use to communicate with the UE based on a DOF mismatch between an antenna port of the first TRP or the second TRP and at least one antenna module of the UE. For example, the UE can receive an indication of a DOF for each antenna port of the first TRP or the second TRP from one or both of the first TRP or the second TRP, and the UE can select a set of beams corresponding to (e.g., formed by) an antenna port having a DOF that is within a threshold DOF mismatch of a DOF of at least one antenna module of the UE. In other words, if a first TRP transmits a first beam from a first port having a first DOF, the first beam is received at a first antenna module of the UE having a second DOF that is within a threshold DOF mismatch of the first DOF, the UE can select the first beam for communication between the first TRP and the UE. The UE can similarly select and indicate beams for the second TRP to use for communication between the second TRP and the UE, and in some implementations, the first TRP and the second TRP can use the indicated beams for joint communication between the TRPs and the UE.

[0047] In some aspects, the UE can select and indicate the set of beams during a synchronization / initial acquisition or access or beam refinement procedure with the first TRP and the second TRP. For example, the UE can receive a number of downlink reference signals (e.g., synchronization signal blocks (SSBs) or channel state information reference signals (CSI-RSs), etc.) from the first TRP and the second TRP via each of the antenna ports of the first TRP and the second TRP. Based on the indication of the DOF for each antenna port of the first TRP and the second TRP and a signal strength of the downlink reference signals at at least one antenna module of the UE, the UE can identify a set of beams that the first TRP and the second TRP can use for joint communication with the UE. For example, the UE can receive a first SSB (which can correspond to a first beam) from a first port of the first TRP at a first antenna module of the UE, the first port is configured with a first DOF, and the first antenna module of the UE is configured with a second DOF, and if the UE determines that the first DOF and the second DOF are similar (e.g., within a threshold DOF mismatch or within a threshold range of each other), the UE can transmit an indication of the first port to indicate to the first TRP to use the first beam to communicate with the UE. In some implementations, the UE can indicate the first port based on transmitting an indication of a transmission configuration indicator (TCI) state corresponding to the first port.

[0048] Particular aspects of the subject matter described in this disclosure can be implemented to realize one or more of the following potential advantages. The described techniques can be implemented to establish a more robust and reliable communication link between a UE, a first TRP, and a second TRP in a multi-TRP deployment. For example, based on indicating a set of beams that the first TRP and the second TRP can use for joint communication with the UE according to a DOF mismatch between antenna ports of the first TRP and the second TRP and antenna modules of the UE, the UE and the TRPs can communicate using beams from antenna ports or modules with similarly tuned radio frequency chains. Such use of similarly tuned radio frequency chains can increase signal strength of communications between the UE and the TRPs, which in turn can increase the likelihood of successful communications between the UE and the TRPs. Thus, the UE, the first TRP, and the second TRP can experience greater connectivity, higher data rates, increased throughput, or higher spectral efficiency, among other benefits. Some aspects of the subject matter described in this disclosure can also be used for more reliable information transfer, as diversity benefits can be improved through DOF matching at the TRPs and the UE.

[0049] Figure 1 An example of a wireless communications system 100 that supports techniques for indicating beams in a multi-TRP point system based on DOF mismatch is shown. The wireless communications system 100 can include one or more base stations 105, one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 can be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, or a New Radio (NR) network. In some examples, the wireless communications system 100 can support enhanced broadband communications, ultra-reliable (e.g., mission critical) communications, low-latency communications, or communications with low-cost and low-complexity devices, or any combination thereof.

[0050] The base stations 105 can be dispersed throughout the geographic area 100 and can be devices in different forms or having different capabilities. The base stations 105 and the UEs 115 can wirelessly communicate with one another via one or more communication links 125. Each base station 105 can provide a coverage area 110 over which

[0051] The UEs 115 can be dispersed throughout the coverage areas 110 of the wireless communications system 100, and each UE 115 can be stationary, or mobile, or both. The UEs 115 can be devices in different forms or having different capabilities. Some example UEs 115 illustrated in FIG. 1A include a cellular phone 115a, a wearable device 115b (such as a smart watch), a tablet 115c, a laptop computer 115d, and a vehicle 115e (such as an autonomous vehicle).Figure 1 Some example UEs 115 are illustrated. The UEs 115 described herein can be able to communicate with various types of devices, such as other UEs 115, base stations 105, or network equipment (e.g., core network nodes, relay devices, integrated access and backhaul (IAB) nodes, or other network equipment), as shown in Figure 1 .

[0052] The base stations 105 can communicate with the core network 130, or with one another, or both. For example, the base stations 105 can interface with the core network 130 through one or more backhaul links 120 (e.g., via an SI, N2, N3, or another interface). The base stations 105 can communicate with one another over the backhaul links 120 (e.g., via an X2, Xn, or other interface) either directly (e.g., directly between base stations 105), or indirectly (e.g., via core network 130), or both, in some examples, the backhaul links 120 can be or include one or more wireless links.

[0053] One or more of the base stations 105 described herein can include or can be referred to as a base transceiver station, a radio base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB), a next-generation NodeB or giga-NodeB (either of which can be referred to as a gNB), a Home NodeB, a Home eNodeB, or some other suitable terminology.

[0054] A UE 115 can include or can be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable terminology, where the “device” can also be referred to as a unit, a station, a terminal, or a client, among other examples. A UE 115 can also include or can be referred to as a personal electronic device such as a cellular phone, a personal digital assistant (PDA), a tablet computer, a laptop computer, or a personal computer. In some examples, a UE 115 can include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which can be implemented in various objects such as appliances, or vehicles, or meters, among other examples.

[0055] The UEs 115 described herein can be able to communicate with various types of devices, such as other UEs 115 that can sometimes act as relays or the base stations 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, as shown in Figure 1

[0056] ​The UEs 115 and the base stations 105 can wirelessly communicate with one another via one or more communication links 125 over one or more carriers. The term “carrier” refers to a set of radio frequency spectrum resources (e.g., frequency channels) with a defined physical layer structure used for communicating communications links 125. For example, a carrier used for a communication link 125 can include a portion of an operating band (e.g., a bandwidth part (BWP)) that is conformant with one or more physical layer structures defined for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer structure can carry acquisition signaling (e.g., synchronization signals, system information), control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 can support communication with a UE 115 using carrier aggregation or multi-carrier operation. According to carrier aggregation, a UE 115 can be configured with multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation can be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers.

[0057] In some examples (e.g., in carrier aggregation configurations), a carrier can also have acquisition signaling or control signaling that coordinates operations for other carriers. A carrier can be associated with a frequency channel (e.g., an evolved universal mobile telecommunication system terrestrial radio access (E-UTRA) absolute radio frequency channel number (EARFCN)) and can be positioned according to a channel raster to facilitate discovery by UEs 115. A carrier can be operated in a standalone mode where initial acquisition and connection occur via the carrier, or the carrier can be operated in a non-standalone mode where a connection is anchored through a different carrier (e.g., of the same or a different radio access technology).

[0058] The communication links 125 shown in wireless communications system 100 can include uplink transmissions from a UE 115 to a base station 105, or downlink transmissions from a base station 105 to a UE 115. Carriers can carry downlink or uplink communications (e.g., in an FDD mode) or can be configured to carry downlink and uplink communications (e.g., in a TDD mode).

[0059] A carrier can be associated with a particular bandwidth of the radio frequency spectrum, and in some examples the carrier bandwidth can be referred to as a “system bandwidth” of the carrier or wireless communications system 100. For example, the carrier bandwidth can be one of a number of determined bandwidths for carriers of a particular radio access technology (e.g., 1.4, 3, 5, 10, 15, 20, 40, or 80 megahertz (MHz)). Devices of wireless communications system 100 (e.g., base stations 105, UEs 115, or both) can have hardware configurations that support communications over a particular carrier bandwidth or can be configurable to support communications over one of a set of carrier bandwidths. In some examples, wireless communications system 100 can include base stations 105 or UEs 115 that support simultaneous communications via carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 can be configured for operating over portions (e.g., sub-bands, BWPs) or all of a carrier bandwidth.

[0060] Signal waveforms transmitted over a carrier can be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM)). In OFDM systems, a resource element can consist of one symbol period (e.g., the duration of one modulation symbol) and one subcarrier, where the symbol period and subcarrier spacing are inversely related. The number of bits carried by each resource element can depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both). Thus, the more resource elements that a UE 115 receives and the higher the order of the modulation scheme, the higher the data rates for the UE 115 can be. A wireless communications resource can refer to a combination of a radio frequency spectrum resource, a time resource, and a spatial resource (e.g., spatial layers or beams), and the use of multiple spatial layers can further increase the data rate for communications with a UE 115.

[0061] One or more numerologies can be supported for a carrier, where a numerology can include a subcarrier spacing (Δf) and a cyclic prefix. A carrier can be partitioned into one or more BWPs with the same or different numerologies. In some examples, a UE 115 can be configured with multiple BWPs. In some examples, a single BWP for a carrier can be active at a given time, and communications for a UE 115 can be restricted to one or more active BWPs.

[0062] Time can be partitioned into units of time that can, for example, be referred to as a T s = 1 / (Δf max · N f ) seconds, where Δf maxNscsmax f may represent a multiple of the maximum supported Discrete Fourier Transform (DFT) size) to represent time intervals for base stations 105 or UEs 115. Time intervals for the communications resources can be organized as radio frames, each

[0063] Each frame can include a plurality of sequentially numbered subframes or slots, and each subframe or slot can have the same duration. In some examples, a frame can be partitioned (e.g., in the time domain) into subframes, and each subframe can be further partitioned into a plurality of slots. Alternatively, each frame can include a variable number of slots, and the number of slots can depend on the subcarrier spacing. Each slot can include a plurality of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period). In some wireless communications systems 100, slots can be further partitioned into mini-slots containing one or more symbols. Excluding the cyclic prefix, each symbol period can contain one or more (e.g., N f The duration of a symbol period can depend on the subcarrier spacing or the operating band.

[0064] A subframe, a slot, a mini-slot, or a symbol can be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and can be referred to as a transmission time interval (TTI). In some examples, the TTI duration (e.g., the number of symbol periods in a TTI) can be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communications system 100 (e.g., in the time domain) can be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs)).

[0065] Physical channels can be multiplexed on a carrier according to various techniques. A physical control channel and a physical data channel can be multiplexed on a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET)) for a physical control channel can be defined by a number of symbol periods and can extend for one or more symbol periods in a time period of a carrier. One or more control regions (e.g., CORESETs) can be configured for a set of UEs 115. For example, one or more of the UEs 115 can monitor or search control regions for control information according to one or more search space sets, and each search space set can include one or more control channel candidates arranged in a cascaded manner for one or more aggregation levels. An aggregation level for a control channel candidate can refer to a number of control channel resources (e.g., control channel elements (CCEs)) associated with encoded information for a control information format having a given payload size. Search space sets can include common search space sets configured for sending control information to multiple UEs 115 and UE-specific search space sets configured for sending control information to a specific UE 115.

[0066] Each base station 105 can provide communication coverage for one or more cells (e.g., macro cells, small cells, hot spots, or other types of cells, or various combinations thereof). The term “cell” can refer to a logical communication entity used for communication with a base station 105 (e.g., through a carrier) and can be associated with a identifier, such as a physical cell identifier (PCID), a virtual cell identifier (VCID), or otherwise. In some examples, a cell can also refer to a geographical area 110 or a subset of a geographical area 110 (e.g., a sector) over which a logical communication entity operates. The size of such a cell can vary, depending on various factors such as capacity requirements, coverage requirements, and the like. For example, a cell can be or include a structure, a subset of a structure, an outdoor space between or overlapping with geographical coverage areas 110, and the like.

[0067] Macro cells can typically cover relatively large geographic areas (e.g., 5-10 miles in radius) and can allow for unrestricted access by UEs 115 with service subscriptions with the network provider supporting the macro cell. Small cells can include pico, femto, and micro cells. Small cells can be deployed indoors and / or outdoors to provide local area coverage over a relatively small geographic region (e.g., a home, a business, a campus, a municipal area, etc.). A UE 115 can be able to access a small cell through a restricted access group (RAG) that is not allowed to access the macro cell. Small cells can support higher performance and / or higher capacity, lower power consumption, and / or increased coverage compared to macro cells. A UE 115 can be associated with, or restricted to access, only a single RAG. A small cell can support a single RAG. A base station 105 can support one or multiple cells, and can also support communication with UEs 115 using one or more component carriers.

[0068] In some examples, a carrier can support multiple cells, and different cells can be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) providing access for different types of devices.

[0069] In some examples, base stations 105 can be movable and therefore provide communication coverage for a moving geographic coverage area 110. In some examples, different geographic coverage areas 110 associated with different technologies can overlap, but the different geographic coverage areas 110 can be supported by the same base station 105. In other examples, the overlapping geographic coverage areas 110 associated with different technologies can be supported by different base stations 105. The wireless communications system 100 can include, for example, a heterogeneous network in which different types of base stations 105 provide coverage for various geographic coverage areas 110 using the same or different radio access technologies.

[0070] The wireless communications system 100 can support synchronous or asynchronous operation. For synchronous operation, the base stations 105 can have similar frame timings, and transmissions from different base stations 105 can be approximately aligned in time. For asynchronous operation, the base stations 105 can have different frame timings, and transmissions from different base stations 105 can not be aligned in time. The techniques described herein can be used for either synchronous or asynchronous operation.

[0071] Some UEs 115, such as MTC or IoT devices, can be low cost or low complexity devices, and can provide for automated communication between machines (e.g., via Machine-to-Machine (M2M) communication). M2M communication or MTC can refer to data communication technologies that allow devices to communicate with one another or a base station 105 without human intervention. In some examples, M2M communication or MTC can include communications from devices that integrate sensors or meters to measure or capture information and relay such information to a central server or application program that makes use of the information or presents the information to humans in an intuitive manner. Some UEs 115 can be designed to collect information or enable automated behavior of machines or other devices. Examples of applications for MTC devices include smart metering, inventory monitoring, water level monitoring, equipment monitoring, healthcare monitoring, wildlife monitoring, climate and geological event monitoring, fleet management and tracking, remote security sensing, physical access control, and transaction-based business processes.

[0072] Some UEs 115 can be configured to employ operating modes that reduce power consumption, such as a half-duplex communications (e.g., a mode that supports one-way communication via transmission or reception, but not simultaneously). In some examples, half-duplex communications can be performed at a reduced peak rate. Other power conservation techniques for UEs 115 include entering a power saving deep sleep mode when not engaging in active communications, entering a power saving shallow sleep mode when not engaging in active communications, operating over a limited bandwidth (e.g., according to a narrowband

[0073] The wireless communications system 100 can be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 can be configured to support ultra-reliable low-latency (URLLC) or mission critical communications. UEs 115 can be designed to support ultra-reliable, low-latency, or critical functions (e.g., mission critical functions). Ultra-reliable communications can include private communications or group communications and can be supported by one or more mission critical services such as mission critical push-to-talk, mission critical video (MCVideo), or mission critical data (MCData). Support for mission critical functions can include prioritization of services, and mission critical services can be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, mission critical, and ultra-reliable low- latency can be used interchangeably herein.

[0074] In some examples, UE 115 can also be able to communicate directly with other UEs 115 over device-to-device (D2D) communication link 135 (e.g., using a peer-to-peer (P2P) or D2D protocol). One or more UEs 115 utilizing D2D communications can be within the geographic coverage area 110 of a base station 105. Other UEs 115 in such a group can be outside the geographic coverage area 110 of a base station 105 or be otherwise unable to receive transmissions from a base station 105. In some examples, groups of UEs 115 communicating via D2D communications can utilize a one-to-many (1 :M) system in which each UE 115 transmits to every other UE 115 in the group. In some examples, a base station 105 facilitates the scheduling of resources for D2D communications. In some other examples, D2D communications are carried out between UEs 115 without the involvement of a base station 105.

[0075] In some systems, D2D communication link 135 can be an example of a communication channel, such as a sidelink communication channel, between vehicles (e.g., UEs 115). In some examples, vehicles can communicate using vehicle-to-everything (V2X) communications, vehicle-to-vehicle (V2V) communications, or some combination of these. A vehicle can signal information related to traffic conditions, signal scheduling, weather, safety, emergencies, or any other information related to V2X systems. In some examples, vehicles in a V2X system can communicate with roadside infrastructure, such as roadside units, or with the network via one or more network nodes (e.g., base stations 105) using vehicle-to-network (V2N) communications, or both.

[0076] The core network 130 can provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing, or mobility functions. The core network 130 can be an evolved packet core (EPC) or 5G core (5GC), which can include at least one control plane entity that can manage access and mobility (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) and at least one user plane entity that can route packets or interconnect to external networks (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)). The control plane entity can manage non-access stratum (NAS) functions, such as mobility, authentication, and bearer management for UEs 115 served by base stations 105 associated with the core network 130. User IP packets can be transferred through the user plane entity, which can provide IP address allocation as well as other functions. The user plane entity can be connected to the IP services 150 of the Internet 155. The IP services 150 can include access to the Internet, Intranet(s), an IP multimedia subsystem (IMS), or a packet-switched streaming service.

[0077] Some of the network devices, such as a base station 105, can include subcomponents such as an access network entity 140, which can be an example of an access node controller (ANC). Each access network entity 140 can communicate with UEs 115 through one or more other access network transmission entities 145, which can be referred to as radio heads, smart radio heads, or TRPs. Each access network transmission entity 145 can include one or more antenna panels. In some configurations, various functions of each access network entity 140 or base station 105 can be distributed across various network devices (e.g., radio heads and ANCs) or consolidated into a single network device (e.g., a base station 105).

[0078] The wireless communications system 100 can operate using one or more frequency bands, typically in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band, since the wavelengths range from approximately one decimeter to one meter in length. UHF waves can be blocked or redirected by buildings and environmental features, but the waves can penetrate structures sufficiently for a macro cell to provide service to UEs 115 located indoors. Transmission of UHF waves can be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to transmission using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.

[0079] The wireless communications system 100 can also operate in a super high frequency (SHF) region, also known as the centimeter band, from 3 GHz to 30 GHz, or in an extremely high frequency (EHF) region, also known as the millimeter band, from 30 GHz to 300 GHz, for example. In some examples, the wireless communications system 100 can support millimeter wave (mmW) communications between UEs 115 and base stations 105, and EHF antennas can be even smaller and more closely spaced than UHF antennas. In some examples, this can facilitate using antenna arrays that can provide directional routing. However, the propagation of EHF transmissions can be subject to even greater atmospheric attenuation and shorter range than SHF or UHF transmissions. Techniques disclosed herein can be employed across transmissions that use one or more different frequency regions, and designated use of bands across these frequency regions can differ by country or regulating body.

[0080] The wireless communications system 100 can utilize both licensed and unlicensed radio frequency spectrum bands. For example, the wireless communications system 100 can employ License Assisted Access (LAA), LTE-Unlicensed (LTE-U) radio access technology, or NR technology in an unlicensed frequency spectrum band, such as the 5 GHz industrial, scientific, and medical (ISM) band. When operating in unlicensed frequency spectrum bands, devices such as base stations 105 and UEs 115 can perform listen-before talk (LBT) procedures prior to communicating with one another over those bands. In some examples, operations in unlicensed frequency spectrum bands can be based on a carrier aggregation configuration in which a primary component carrier (PCC) operates in a licensed frequency spectrum band, and one or more secondary component carriers (SCCs) operate in an unlicensed frequency spectrum band. Operations in unlicensed spectrum may, in some examples, include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.

[0081] The base stations 105 or UEs 115 can be equipped with multiple antennas, which can be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a base station 105 or a UE 115 can be co-located within one or more antenna arrays or antenna panels, which can support MIMO operations or transmit or receive beamforming. In some examples, one or more base station antennas or antenna arrays can be co-located with a antenna assembly, for example, an antenna tower. In some examples, the antennas of a base station 105 can be located in diverse geographic locations, such as on different support structures, buildings, or other structures. A base station 105 can have antenna arrays with a number of rows and columns of antenna ports that the base station 105 can use to support beamforming of communications to UEs 115. Similarly, a UE 115 can have one or more antenna arrays that can support various MIMO or beamforming operations. Additionally or alternatively, antenna panels can support radio frequency beamforming of signals transmitted via the antenna ports.

[0082] The base stations 105 or the UEs 115 can use MIMO communications to exploit multipath signal propagation and increase the spectral efficiency. Such techniques can be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Similarly, the multiple signals can be received by the receiving device via different antennas or different combinations of antennas. Each of the multiple signals can be referred to as a spatial stream, and can carry bits associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers can be associated with different antenna ports used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO), where multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO), where multiple spatial layers are transmitted to multiple devices.

[0083] Beamforming, which can also be referred to as spatial filtering, directional transmission, or directional reception, is a signal processing technique that can be used at a transmitting device or a receiving device (e.g., a base station 105 or a UE 115) to shape or steer a beam of energy in a specific direction. Beamforming can be achieved by combining the signals of multiple antennas, which can include as few as one transmitter or receiver. The combination of signals can be done in such a way that the antenna elements act as a phased antenna array, with the signals from different antenna elements being phase-shifted in a way that the signals constructively interfere with each other, resulting in a signal that is strong in a particular direction. The different phase-shifts can be achieved by adjusting the timing, and / or the amplitude, of the signal transmitted by each of the antenna elements. The adjustments associated with each of the antenna elements can be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the base station 105 or UE 115 antenna array, or with respect to some other orientation).

[0084] As part of the beamforming operations, the base stations 105 or UEs 115 can use beam sweeping techniques. For example, a base station 105 can use multiple antennas or antenna arrays (e.g., antenna panels) to conduct beamforming operations for directional communications with a UE 115. The base station 105 can transmit multiple signals in different directions, each with a respective beam. For example, the base station 105 can transmit a signal according to different beamforming weight sets associated with different transmission directions. The transmissions in the different beam directions can be used, e.g., by a transmitting device such as a base station 105 or by a receiving device such as a UE 115, to identify a beam direction for subsequent transmission or reception by the base station 105.

[0085] Base stations 105 can transmit some signals (e.g., data signals associated with a particular receiving device, such as a UE 115) in a single beam direction (e.g., associated with the receiving device). In some examples, the beam direction associated with transmissions along a single beam direction can be determined based on a signal that was transmitted in one or more beam directions. For example, a UE 115 can receive one or more of the signals transmitted by the base station 105 in different directions, and can report to the base station 105 an indication of the signal it received with a highest signal quality, or otherwise acceptable to the UE 115.

[0086] In some examples, transmissions by a device (e.g., by a base station 105 or a UE 115) can be performed using multiple beam directions, and the device can use a combination of digital precoding or radio frequency beamforming to generate a combined beam for transmissions (e.g., from a base station 105 to a UE 115). The UE 115 can report feedback indicating precoding weights for one or more beam directions, and the feedback can correspond to a configured number of beams across a system bandwidth or one or more sub-bands. The base station 105 can transmit reference signals (e.g., cell-specific reference signals (CRS), CSI-RS) that can be precoded or unprecoded. The UE 115 can provide feedback for beam selection, which can be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel type codebook, a linear combination type codebook, a port selection type codebook). Although these techniques are described with reference to signals transmitted in one or more directions by the base station 105, a UE 115 can employ similar techniques for transmitting signals multiple times in different directions (e.g., for identifying beam directions for subsequent transmissions or receptions by the UE 115) or transmitting a signal in a single direction (e.g., for transmitting data to a receiving device).

[0087] When receiving various signals from a base station 105 (such as synchronization signals, reference signals, beam selection signals, or other control signals), a receiving device (e.g., a UE 115) can try multiple receive configurations (e.g., directional listening). For example, the receiving device can try multiple receive directions by receiving via different antenna subarrays, by processing received signals according to different antenna subarrays, by receiving according to different receive beamforming weight sets applied individually to signal streams received at multiple antenna elements of an antenna array, or by processing received signals according to different receive beamforming weight sets applied individually to signal streams received at multiple antenna elements of an antenna array, any of which can be referred to as “listening” according to different receive configurations or receive directions. In some examples, the receiving device can use a single receive configuration to receive along a single beam direction (e.g., when receiving a data signal). The single receive configuration can be aligned in a beam direction determined based on listening according to different receive configuration directions.

[0088] Wireless communications system 100 can be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or Packet Data Convergence Protocol (PDCP) layer can be IP -based. A Radio Link Control (RLC) layer can perform packet segmentation and reassembly to communicate over logical channels. A Medium Access Control (MAC) layer can perform priority handling and multiplexing of logical channels into transport channels. The MAC layer can also use error detection techniques, error correction techniques, or both, to support retransmissions at the MAC layer to improve link efficiency. In the control plane, the Radio Resource Control (RRC) protocol layer can provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a base station 105 or core network 130, which can support radio bearers for user plane data. At the physical layer, transport channels can be mapped to physical channels.

[0089] The UEs 115 and the base stations 105 can support retransmissions of data to increase the likelihood that data is received successfully. HARQ feedback is one technique of increasing the likelihood that data is received correctly over a communication link 125. HARQ can include a combination of error detection (e.g., using a cyclic redundancy check (CRC)), forward error correction (FEC), and retransmission (e.g., automatic repeat request (ARQ)). HARQ can improve throughput at the MAC layer in poor radio conditions (e.g., low signal-to-noise conditions). In some examples, a device can support same-slot HARQ feedback, where the device can provide HARQ feedback in a specific time slot for data received in a previous time slot. In some other examples, the device can provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0090] As more wireless devices communicate over available spectrum, the demand for communication resources increases, and techniques for efficiently and reliably increasing throughput are desirable. Communication devices, such as UEs 115 and base stations 105, can use additional frequency ranges, and communication devices can achieve greater throughput based on using such additional frequency ranges. In some aspects, such additional frequency ranges can refer to relatively higher frequency ranges. Higher frequency ranges, such as FR2 radio frequency spectrum bands including millimeter wave (mmW) frequency ranges (e.g., frequencies above 6 GHz, such as frequencies between 24.25 - 52.6 GHz) and FR4 radio frequency spectrum bands including higher mmW frequency ranges, such as frequencies between 52.6 GHz - 114.25 GHz, can be used for wireless communication between multiple devices, and transmitting at these higher frequencies can include transmitting at shorter wavelengths, and in some examples, according to beamforming techniques. For example, based on transmitting at shorter wavelengths, signals carried by FR2 or FR4 radio frequency spectrum bands can be more susceptible to interference or path loss, and a transmitting device or a receiving device, or both, can employ beamforming techniques to increase signal strength of such signals carried by FR2 and FR4 radio frequency spectrum bands. Moreover, the present disclosure does not exclude frequency ranges other than FR4, such as 114.25 - 300 GHz, which can be referred to as a “sub-THz” band.

[0091] The UE 115 can employ such beamforming techniques at one or more antenna modules of the UE 115. For example, the UE 115 can directionally transmit or receive a signal at an antenna module based on tuning a radio frequency chain connected to or coupled with the antenna module using a set of phase shifters and gain control stages. In some examples, the UE 115 can use a single set of phase shifters and gain control for each antenna module of the UE 115, and thus, analog or radio frequency beamforming can be constrained (e.g., can be limited by the single set of phase shifters), which can result in poor performance at some frequencies in examples where the UE 115 is communicating on a FR2 or FR4 radio frequency spectrum band. For example, such constrained analog or radio frequency beamforming can result in poor performance in examples where the UE 115 is communicating over a super wide bandwidth. In some examples, the UE 115 can tune or optimize an analog or radio frequency beamforming codebook of the UE 115 or an antenna module of the UE 115 for a certain carrier frequency on a FR2 or FR4 radio frequency spectrum band (over a super wide bandwidth of interest), and such a carrier frequency can be referred to herein as a DOF. In some examples, the UE 115 can operate multiple antenna modules, each having a different analog or radio frequency beamforming codebook, and the UE 115 can configure each antenna module with a DOF (such that the DOFs of the multiple antenna modules of the UE can be the same or can be different).

[0092] Similarly, a base station 105 (which can be an example of or operate as a TRP) can employ such beamforming techniques at one or more antenna panels or antenna ports of the base station 105 based on tuning a radio frequency chain connected or coupled to an antenna panel or antenna port using a set of phase shifters and gain controls. The base station 105 can tune or optimize an analog or radio frequency beamforming codebook of the base station 105 or an antenna panel or port of the base station 105 for a certain carrier frequency on a FR2 or FR4 radio frequency spectrum band (over a super wide bandwidth of interest), and such a carrier frequency can be referred to herein as a DOF, as described herein. In some examples, the base station 105 can operate multiple antenna panels or ports, and the base station 105 can configure each antenna panel or port with a DOF (such that the DOFs of the multiple antenna panels or ports of the base station 105 can be the same or can be different).

[0093] The UE 115 and the base station 105 can configure their respective radio frequency chains or ports with varying DOFs, such that a first DOF configured at a first antenna module of the UE 115 can be different than a second DOF of a first port of the base station 105. Such variation in DOFs between the UE 115 and the base station 105 can impact the likelihood of the UE 115 and the base station 105 successfully communicating with each other. For example, if the first DOF of the first antenna module of the UE 115 is greater than a threshold difference from the second DOF of the first port of the base station 105, the UE 115 or the base station 105 can fail to detect or receive signaling (due to signal strength distortion) in an example in which they are communicating via the first antenna module of the UE 115 and the first port of the base station 105, which can result in a failure in communication or loss in performance (such as data rate or reliability and other examples) between the UE 115 and the base station 105.

[0094] In some implementations of the disclosure, a UE 115 in a multi-TRP deployment can select two or more TRPs for communication with the network based on DOFs configured at ports of the TRPs. Additionally, in some examples, the UE 115 can transmit beam selection signaling based on variation in DOFs between the UE 115 and the TRPs to indicate one or more beams for each TRP to use for joint / multi-TRP communication with the UE 115. For example, the UE 115 can transmit an indication of a set of candidate beams to one or more of the two or more selected TRPs, and each beam in the set of candidate beams can be associated with a port of a selected TRP that has a DOF within a threshold difference of a DOF of the UE 115. The UE 115 can apply this technique to refine a beam training or selection process based on DOF mismatches between the UE 115 and the TRPs to scenarios in which the UE 115 communicates with multiple TRPs in a multi-TRP deployment, where the UE 115 can receive joint transmissions from the multiple TRPs or perform joint transmissions to the multiple TRPs. Additional details related to this extension of DOF mismatch based beam selection to multi-TRP deployments are described herein (including with reference to Figure 2 and 3 ).

[0095] Figure 2 An example of a wireless communications system 200 that supports techniques for indicating beams in a multi-TRP system based on DOF mismatches is shown. The wireless communications system 200 can implement aspects of the wireless communications system 100. For example, the wireless communications system 200 shows a UE 115-a, a TRP 205, a TRP 210, and a TRP 215, which can be in a multi-TRP deployment as described herein (including with reference to FIG. 1). The UE 115-a can be configured to communicate with the TRPs 205, 210, and 215 via a set of beams 220, 225, and 230, respectively. The beams 220, 225, and 230 can be associated with a set of DOFs 235, 240, and 245, respectively, that are configured at the UE 115-a. The beams 220, 225, and 230 can also be associated with a set of DOFs 250, 255, and 260, respectively, that are configured at the TRPs 205, 210, and 215, respectively. Figure 1communication between the UE 115-a and the corresponding device described above. In some implementations, the UE 115-a can transmit beam selection signaling to one or more TRPs in the wireless communication system 200 based on a DOF mismatch between a beam (or corresponding antenna port) of a TRP and at least one antenna module of the UE 115-a to indicate a selection of two or more of the TRPs for joint / multi-TRP communication with the UE 115-a and which beams the selected TRPs can use for the joint / multi-TRP communication with the UE 115-a.

[0096] According to the selection, the UE 115-a can communicate with one or more of the TRP 205, the TRP 210, or the TRP 215. The TRPs in the wireless communication system 200 can be examples of different entities in the network or can be different entities mapped to the same (or similar) logical identifier (ID) or logical entity. For example, in examples where the TRPs in the wireless communication system 200 are different entities and are mapped to the same logical ID, the connection between the UE 115-a and the TRP 205 and the connection between the UE 115-a and the TRP 210 can be understood as connections to the same logical ID. In such examples where the TRP 205 and the TRP 210 are mapped to the same logical ID, the TRP 205 and the TRP 210 can communicate via a fiber connection (such as a “high-end” fiber or wired backhaul connection) and can coordinate via the fiber connection. In some other examples, the TRPs in the wireless communication system 200 can be mapped to different logical IDs and thus can not be able to coordinate via such “high-end” fiber or wired backhaul connections. In other words, coordination between TRPs mapped to different logical IDs can be less (share less information or share information less frequently, among other examples) than coordination between TRPs mapped to the same logical ID.

[0097] In some examples, UE 115-a can receive joint / multi-TRP transmissions from, or transmit joint / multi-TRP transmissions to, two or more of TRP 205, TRP 210, or TRP 215. For example, in examples where UE 115-a operates in a multi-TRP deployment or multi-TRP system, UE 115-a can simultaneously receive joint transmissions from multiple (two or more) TRPs. In such examples, the multiple TRPs participating in the multi-TRP transmissions can coordinate (via wired or wireless backhaul links) the multi-TRP transmissions from each TRP such that UE 115-a simultaneously receives the multi-TRP transmissions from the multiple TRPs. Similarly, UE 115-a can simultaneously transmit to multiple TRPs. Such joint transmissions within a multi-TRP system can increase the likelihood of successful communication between UE 115-a and any of the multiple TRPs with which UE 115-a communicates. For example, in examples where UE 115-a communicates at a higher radio frequency (such as mmW radio frequencies), some systems can support denser TRPs, and joint transmissions from multiple TRPs can increase the signal strength at UE 115-a based on a combining effect at the receive antennas of UE 115-a. Additionally, in some examples, such joint transmissions from multiple TRPs can increase the reliability of communications between UE 115-a and the multiple TRPs.

[0098] UE 115-a, TRP 205, TRP 210, and TRP 215 can communicate over one or more radio frequency spectrum bands, such as FR2 or FR4 radio frequency spectrum bands. The FR4 radio frequency spectrum band (which can be referred to as “upper mmW bands” or “sub-THz range” radio frequencies) can have shorter wavelengths λ than the FR2 radio frequency spectrum band. For example, the FR2 radio frequency spectrum band can include frequencies between 24.25 - 52.6 GHz, and the FR4 radio frequency spectrum band can include frequencies between 52.6 GHz - 114.25 GHz. The frequency range from 114.25 - 300 GHz is sometimes labeled as “sub-THz.” In some implementations, because frequencies in the FR4 radio frequency spectrum band have shorter wavelengths than frequencies in the FR2 radio frequency spectrum band, more antenna elements can be packed into the same physical aperture in examples where a device is configured to communicate over the FR4 radio frequency spectrum band than in examples where a device is configured to communicate over the FR2 radio frequency spectrum band, which can result in a larger antenna array (a larger number of antenna elements) in examples where a device is configured to communicate over the FR4 radio frequency spectrum band. As the demand for greater throughput and capacity continues, it is possible to extend to higher radio frequency spectrum bands, such as the FR5 radio frequency spectrum band, which can result in an even larger antenna array.

[0099] Devices operating in FR2 or FR4 radio frequency spectrum bands can use a portion or subset of the entire radio frequency spectrum band. For example, a device operating on the FR4 radio frequency spectrum band can receive an allocation of a subset frequency range within the 52.6-114.25 GHz frequency range. Such a subset frequency range in FR2 or FR4 radio frequency spectrum bands can be relatively wide compared to frequency allocations in other radio frequency spectrum bands, and thus, can be referred to herein as an ultra-wide bandwidth. For example, a bandwidth of approximately 14 GHz, such as the 14 GHz subset of the FR4 radio frequency spectrum band, can be available to devices across multiple geographic locations, and in some examples, devices communicating over such an ultra-wide bandwidth can experience performance and beamforming gain, such as greater throughput. In some aspects, a device can receive an allocation of such a 14 GHz wide bandwidth from 57-71 GHz.

[0100] Some devices can communicate over an ultra-wide bandwidth, such as an approximately 14 GHz bandwidth range, using a single radio frequency chain, and since such devices can use a single set of phase shifters for a single radio frequency chain, analog or radio frequency beamforming can be constrained (or limited to some carrier frequencies) based on using a single radio frequency link, which can result in poorer performance at some frequencies. Such poorer performance at some frequencies due to limited analog or radio frequency beamforming can be referred to as “beam squinting.” Further, some devices can adjust or optimize their radio frequency chain (e.g., analog or radio frequency beamforming codebook) for a certain carrier frequency (which can be referred to herein as a DOF) on an ultra-wide bandwidth of interest, such as the 14 GHz wide bandwidth from 57-71 GHz.

[0101] Accordingly, a device can experience a greater likelihood of successful communication with another device also using the same or similar DOF. In other words, a DOF can correspond to a frequency for which a radio frequency chain is tailored for peak (or increased) beamforming array gain relative to other frequencies within an ultra-wide bandwidth frequency allocation. Additionally, a DOF of a node or device can also be referred to as a measure of a frequency for which a half-wavelength is equal to an inter-element spacing on an antenna array or panel in operation. For example, for a certain wavelength λ, an inter-element spacing can be d = λ / 2, and a corresponding DOF can equal c / λ = c / 2d, where c refers to the speed of light. Accordingly, an antenna panel of a device can have a DOF based on an inter-element spacing of the antenna panel’s design or configuration, and the device can adjust or tailor the DOF of the antenna panel based on a radio frequency chain configured or tuned to the antenna array or panel.

[0102] The DOFs can be specific to a device and radio frequency chain and can be unknown at a device on the other end of the link. For example, UE 115-a can tune or optimize an analog or radio frequency codebook of UE 115-a for a first DOF, and TRPs 205, 210, and 215 can not be aware of the first DOF used by UE 115-a. Thus, in some examples, a communicating device can signal (e.g., broadcast) or otherwise share information related to configured DOFs. In some aspects, the signaling can be from a TRP or base station to a UE 115. In some other aspects, the signaling can be from a UE 115 to a TRP or base station.

[0103] However, using more specific or more fine-grained DOFs to communicate over such ultra-wide bandwidths can potentially result in DOF mismatches between devices (e.g., between UE 115-a, TRPs 205, 210, and 215). For example, different devices or nodes (such as base stations, TRPs, UEs 115, customer premises equipment (CPE), relay nodes, repeater nodes, or IAB nodes) can have different DOFs. For example, UE 115-a, TRPs 205, 210, and 215 can each configure ports at the respective devices with different (at least partially) DOFs. For example, TRP 205 can configure a first port of TRP 205 with DOF 235 and can configure a second port of TRP 205 with DOF 240. Similarly, TRP 210 can configure a first port of TRP 210 with DOF 245 and can configure a second port of TRP 210 with DOF 240, and TRP 215 can configure a first port of TRP 225 with DOF 245 and can configure a second port of TRP 215 with DOF 235. Further, although TRPs 205, 210, and 215 are shown as each sharing some common DOFs, TRPs 205, 210, and 215 can configure respective ports of TRPs 205, 210, and 215 such that the configured DOFs are all different from each other without departing from the scope of the present disclosure.

[0104] In some examples, intra-cell multi-TRP communications and inter-cell multi-TRP communications with the same cell identifier (ID) can operate on the same radio frequency spectrum band or the same component carrier. For example, intra-cell or inter-cell multi-TRP communications can operate on the same FRx (where x = 1, 2, 3, 4, or 5) such that FR3 can include 7.125 - 24.25 GHz, and FR4 can include 52.6 - 114.25 GHz. Further, the FR4 radio frequency band can include a subset band referred to as FR4-la, which can include frequencies between 52.6 - 71 GHz out of the 52.6 - 114.25 GHz included within the FR4 radio frequency spectrum band. The TRPs (such as two or more of the TRPs 205, 210, and 215) can coordinate via a wired or wireless backhaul connection and transmit the same symbol from different (non-co-located) TRPs in different ways. Such same symbol transmission from different TRPs based on backhaul coordination can be referred to herein as joint transmission or joint / multi-TRP transmission. In such examples where multi-TRP communications operate on the same FR, the TRP or UE 115-a can select which beams to use for communications between the TRP and the UE 115-a based on one or more signal strength measurements, such as reference signal received power (RSRP) measurements. However, in some examples, RSRP measurements can be narrowband-based measurements, and the UE 115-a can have difficulty measuring RSRP for wide bandwidth communications, such as ultra-wideband communications that can exist in FR2, FR4, or FR5 / “sub-THz” radio frequency spectrum bands.

[0105] However, in some other examples, the TRPs can communicate on different radio frequency spectrum bands or different component carriers (rather than the same radio frequency spectrum band or the same component carrier) such that joint / multi-TRP communications can be carried on different radio frequency spectrum bands. For example, in some scenarios, the TRPs can communicate on different radio frequency spectrum bands such that some TRPs can communicate on FRx and some other TRPs can communicate on FRy (where x or y = 1, 2, 3, 4, or 5). Similarly, the TRPs can communicate on multiple radio frequency spectrum bands (such that one TRP can operate a first antenna panel or port at FRx and a second antenna panel or port at FRy).

[0106] In examples where FRx or FRy is supported or otherwise includes ultra-wide bandwidth operation, such as 24-48 GHz which can occur on FR2 or 57-71 GHz which can occur on FR4-la, the corresponding TRP can configure each of the sub-arrays or panels used to transmit or receive signals at the TRP side of the communication link with DOF. At the other end of the link, UE 115-a can also configure each of the number of antenna modules with DOF within any of the FRx or FRy radio frequency spectrum bands (e.g., based on the capabilities of UE 115-a) for communication (transmission or reception) operations at UE 115-a. Thus, based on the multiple TRPs and the radio frequency spectrum bands over which UE 115-a can communicate, the selection or configuration of DOF can vary across the radio frequency chains or ports at the multiple TRPs and can vary across the radio frequency chains, ports, or antenna modules at UE 115-a.

[0107] Thus, and based on ultra-wide bandwidth operation over one or both of the FRx or FRy radio frequency spectrum bands, the DOF and beams used for communication between UE 115-a and the multiple TRPs can be mismatched, which can result in a lower likelihood of successful communication between UE 115-a and the multiple TRPs. For example, in an example where TRP 205 is operating with DOF 235 and DOF 240 within the FRx radio frequency band and a first antenna module of UE 115-a is operating with DOF within the FRy radio frequency band, and if the communication link between TRP 205 and UE 115-a is via the first antenna module, the communication between TRP 205 and UE 115-a can have a lower likelihood of being successfully received and decoded compared to an example where DOF 235 or DOF 240 and the DOF of UE 115-a are relatively similar or within a threshold range of each other. In other words, the mismatch of DOF can result in a degradation of array gain in the communication relative to an example of DOF matching (or being within a threshold difference of each other).

[0108] In some implementations of the disclosure, the UE 115-a can determine which TRPs to connect to based on a DOF mismatch between each of the multiple TRPs and the UE 115-a. For example, the UE 115-a can receive one or more control messages from one or more of the TRP 205, the TRP 210, or the TRP 215 indicating DOFs supported at each of the TRP 205, the TRP 210, and the TRP 215, and the UE 115-a can select to communicate with one or more of the TRP 205, the TRP 210, or the TRP 215 based on which of the TRPs support DOFs within a threshold range of or mismatched to the one or more DOFs supported at the UE 115-a. Additionally, in some examples, the UE 115-a and the multiple TRPs can perform a beam sweep (on both the FRx and FRy radio frequency spectrum bands) and can signal or otherwise indicate a selected set of beams for joint / multi-TRP communication based on the DOF mismatch between each of the multiple TRPs and the UE 115-a and the beam sweep.

[0109] For example, each of the TRPs 205, 210, and 215 can transmit one or more downlink reference signals (such as SSBs or CSI-RSs, among other examples) to the UE 115-a via different directional beams, and the UE 115-a can determine which beams the TRPs can use to communicate with the UE 115-a based on the signal strength of the received downlink reference signals and the DOF of the ports of the TRP from which the downlink reference signals were transmitted. For example, the TRP 205 can operate two ports, including a first port configured as DOF 235 and a second port configured as DOF 240, and the TRP 205 can transmit one or more SSBs via each port through various beams 220, such as beam 220-a from the first port and beam 220-b from the second port. Similarly, the TRP 210 can operate two ports, including a first port configured as DOF 245 and a second port configured as DOF 240, and the TRP 210 can transmit one or more SSBs via each port through various beams 225, such as beam 225-a from the first port and beam 225-b from the second port. Similarly, the TRP 215 can operate two ports, including a first port configured as DOF 245 and a second port configured as DOF 235, and the TRP 215 can transmit one or more SSBs via each port through various beams 230, such as beam 230-a from the first port and beam 230-b from the second port. In other words, each of the multiple TRPs within the multi-TRP system can scan across several SSBs within a certain frequency range or around some DOFs.

[0110] In some examples, the UE 115-a can receive a mapping (such as a logical mapping) between SSBs from one or more of the plurality of TRPs, and the UE 115-a can determine a cell ID based on receiving and decoding the SSBs. For example, each SSB can include a primary synchronization signal (PSS), a secondary synchronization signal (SSS), and a physical broadcast channel (PBCH) including a master information block (MIB) and one or more system information blocks (SIBs) (such as SIB1, SIB2, etc.). The cell ID can be a function of the MIB, SIB1, and SIB2, and the UE 115-a can determine the cell ID corresponding to the TRP from which the UE 115-a receives the SSBs based on decoding the MIB, SIB1, and SIB2. Thus, the UE 115-a can determine or otherwise identify which TRP the UE 115-a is receiving SSBs from, and the UE 115-a can use the received SSBs to identify which beam the TRP is using to transmit to the UE 115-a if the UE 115-a determines that the TRP is one of the TRPs that the UE 115-a selects for communication based on the DOF mismatch.

[0111] For example, each SSB can include an SSB index associated with a beam direction of the SSB, and the UE 115-a can identify the beam used by the TRP based on the SSB index. In some implementations, the UE 115-a can determine which port the TRP uses to transmit the beam to the UE 115-a, and the UE 115-a can refine its beam selection based on a mismatch between the DOF of the port and the DOF of the receive antenna modules of the UE 115-a. Thus, the UE 115-a can select a TRP with which the UE 115-a can connect, and on which ports the UE 115-a and the selected TRP can communicate based on the DOF mismatch.

[0112] For example, in some examples, UE 115-a can have a DOF that approximates or is similar to DOF 240 (within a threshold mismatch from DOF 240), and accordingly, can determine to communicate with TRP 205 and TRP 210 (as TRP 205 and TRP 210 operate at DOF 240 for at least one port). In such examples, UE 115-a can transmit beam selection signaling that indicates that UE 115-a can establish a connection with TRP 205 and TRP 210, and that TRP 205 can use beam 220-b and TRP 210 can use beam 225-b to communicate with UE 115-a. Additionally, in some examples, UE 115-a can transmit an indication of a difference between the DOF of UE 115-a and DOF 240 supported by TRP 205 and TRP 210 within or in addition to the beam selection signaling. Accordingly, TRP 205 and TRP 210 can identify an existing mismatch between DOF 240 and the DOF of UE 115-a, and in some examples, can make scheduling decisions (e.g., involving other nodes with DOFs closer to DOF 240 than DOF 240) or can determine to tune their respective radio frequency chains (to reduce the difference between DOF 240 and the DOF of UE 115-a) based on the indication of the mismatch.

[0113] UE 115-a can accordingly communicate with the selected TRP on the indicated beams. In some implementations, UE 115-a can receive multi-TRP transmissions from the selected TRP via the beams indicated by the beam selection signaling and using the receive beams identified at UE 115-a. In some other implementations, UE 115-a can transmit multi-TRP transmissions to the selected TRP using the transmit beams identified at UE 115-a, and the selected TRP can receive the multi-TRP transmissions via the beams indicated by the beam selection signaling. Based on dynamically selecting which TRPs to connect with according to DOF mismatch across multiple TRPs and UE 115-a, UE 115-a can experience greater likelihood of successful communication because UE 115-a and the selected TRP can communicate via ports, antenna panels, or antenna modules, etc. that are configured for relatively high beamforming array gain at similar frequencies (frequencies within a threshold range of each other). Additionally or alternatively, UE 115-a can select which beams to use to communicate with the selected TRP based on interference considerations. For example, UE 115-a can select which beams the selected TRP can use to communicate with UE 115-a, and which beams UE 115-a can use to communicate with the selected TRP, based on selecting beams associated with out-of-band emissions (or out-of-band emission metrics) that are below an out-of-band emission threshold.

[0114] Additionally, in some examples, the UE 115-a can identify beams from the UE 115-a to use for communicating with the TRPs based on SSB indices, which can indicate beam directions associated with corresponding SSBs. For example, the UE 115-a can identify one or more receive beams (such as a pair of receive beams) to use for receiving a multi-TRP transmission (such as a spatial division multiplexing (SDM) multi-TRP transmission) in the downlink. In examples where the selected TRPs operate on different radio frequency spectrum bands (e.g., on FRx and FRy, where FRx or FRy can be FR2, FR3, FR4, or FR5), the pair of receive beams can include a first beam that the UE 115-a can use to receive the multi-TRP transmission on FRx and a second beam that the UE 115-a can use to receive the multi-TRP transmission on FRy. Additionally or alternatively, the UE 115-a can identify one or more transmit beams (such as a pair of transmit beams) to use for transmitting a multi-TRP transmission (such as an SDM multi-TRP transmission) in the uplink. In examples where the selected TRPs operate on different radio frequency spectrum bands (e.g., on FRx and FRy, where FRx or FRy can be FR2, FR4, or FR5), the pair of transmit beams can include a first beam that the UE 115-a can use to transmit the multi-TRP transmission on FRx and a second beam that the UE 115-a can use to transmit the multi-TRP transmission on FRy.

[0115] Accordingly, the UE 115-a can select which of the TRPs 205, 210, and 215 the UE 115-a can connect with based on a mismatch between the DOF of each TRP and the DOF of the UE 115-a, and can determine which beams the selected TRPs can use to communicate with the UE 115-a based on a beam sweeping procedure that can cover various radio frequency spectrum bands, such as FR2 and FR4 radio frequency spectrum bands, based on the radio frequency spectrum bands that the UE 115-a and the TRPs operate on. The UE 115-a can transmit beam selection signaling to one or more of the TRPs (the selected TRPs) indicating which TRPs the UE 115-a selects to communicate with and the beams that the selected TRPs can use to communicate with the UE 115-a. Further, in some implementations, the UE 115-a can include an indication of the beams that the UE 115-a can use to communicate with the selected TRPs in the beam selection signaling.

[0116] In some examples, UE 115-a can dynamically change or adjust the codebook of UE 115-a to dynamically change the DOF for one or more antenna modules of UE 115-a. In such examples, UE 115-a can determine to reselect which TRPs to communicate with (e.g., if another TRP than the TRP that UE 115-a is currently connected to has a DOF that is closer to the new DOF of UE 115-a). Accordingly, UE 115-a can transmit additional signaling (another instance of beam selection signaling) to indicate the newly selected TRP based on the adjusted DOF (new DOF) of UE 115-a. UE 115-a can also transmit an indication of which beams (or antenna panels or ports) the newly selected TRP can use to communicate with UE 115-a, and in some implementations, can indicate the DOF mismatch for each indicated beam.

[0117] Further, although described herein in the context of UE 115-a selecting a TRP and beams of the selected TRP that can be used to communicate with UE 115-a, one or more TRPs can perform similar operations or functions to determine (between them) which TRPs can communicate with UE 115-a based on DOF mismatch between the TRPs and UE 115-a. In such examples where the TRPs can determine which TRPs can establish a connection with UE 115-a, the TRPs can coordinate the determination based on exchanging signaling via backhaul links between the TRPs. For example, UE 115-a can transmit an indication of one or more DOFs supported by UE 115-a to one or more of the TRPs, the TRPs can exchange signaling associated with the one or more DOFs supported by UE 115-a, and the TRPs can determine which of the TRPs can establish a connection with UE 115-a based on a difference between DOFs supported by each of the TRPs and the one or more DOFs supported by UE 115-a.

[0118] Additionally, UE 115-a can transmit one or more uplink reference signals (such as sounding reference signals (SRS)) to the TRPs. The TRPs can determine which beams to use for communication between the selected TRPs and UE 115-a based on receiving the one or more uplink reference signals from UE 115-a, which can be part of an uplink beam training or beam sweeping procedure, and based on knowledge of which ports of the selected TRPs have DOFs similar (within a threshold difference) to the one or more DOFs of UE 115-a. One or more of the selected TRPs can transmit beam selection signaling to UE 115-a indicating the selected TRPs and indicating which beams the selected TRPs or UE 115-a or both can use to communicate with each other.

[0119] Figure 3 An example of a beam selection diagram 300 that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown. Beam selection diagram 300 illustrates a selection of a TRP with which UE 115-b can establish a connection and a selection of beams that the selected TRP can use to communicate with UE 115-b. In some examples, UE 115-b can select to communicate with one or both of TRP 305 or TRP 310 based on a DOF mismatch between an antenna panel of the TRP and an antenna module 350 of UE 115-b.

[0120] For example, TRP 305 can operate antenna panel 315 on a first radio frequency band and can configure antenna panel 315 with a first DOF within the first radio frequency band. Antenna panel 315 can include a number of antenna elements 320, and in some aspects, an inter-element spacing of the antenna elements 320 can affect the first DOF configured at antenna panel 315. Similarly, TRP 310 can operate antenna panel 325 on a second radio frequency spectrum band and can configure antenna panel 325 with a second DOF within the second radio frequency band. Antenna panel 325 can include a number of antenna elements 330, and in some aspects, an inter-element spacing of the antenna elements 330 can affect the second DOF configured at antenna panel 325.

[0121] In some aspects, TRPs 305 and 310 can operate on different radio frequency spectrum bands (such that the first radio frequency spectrum band is different from the second radio frequency spectrum band). For example, TRP 305 can operate on a FRx radio frequency spectrum band, and TRP 310 can operate on a FRy radio frequency spectrum band (such that FRx or FRy can refer to one of FR1, FR2, FR4, or FR5). Alternatively, in some other aspects, TRPs 305 and 310 can operate on the same radio frequency spectrum band (such that the first radio frequency spectrum band is the same as the second radio frequency spectrum band). For example, both TRPs 305 and 310 can operate on a FR2 radio frequency spectrum band or a FR4 radio frequency spectrum band.

[0122] UE 115-b can operate multiple antenna modules 350, including antenna module 350-a, antenna module 350-b, and antenna module 350-c, on one or more radio frequency spectrum bands, and can tune or configure each of the multiple antenna modules 350 to a DOF within the one or more radio frequency spectrum bands to increase or optimize performance of communications on the configured DOF. For example, UE 115-b can configure antenna module 350-a with DOF 355, can configure antenna module 350-b with DOF 360, and can configure antenna module 350-c with DOF 365.

[0123] TRPs 305 and 310 can form one or more directional beams from each antenna panel. For example, TRP 305 can form beam 335 from antenna panel 315 of TRP 305, and TRP 310 can form beam 340 from antenna panel 325 of TRP 310. Similarly, UE 115-b can form one or more directional beams 345, including beam 345-a, beam 345-b, and beam 345-c, from each antenna module 350 of UE 115-b. As shown, solid lines can illustrate direct communication paths between TRP 305 or TRP 310 and UE 115-b, and dashed lines can illustrate indirect (or non-line-of-sight) communication paths between TRP 305 or TRP 310 and UE 115-b (such that signaling via an indirect communication path can reflect off one or more objects). Figure 3 As shown, solid lines can illustrate direct communication paths between TRP 305 or TRP 310 and UE 115-b, and dashed lines can illustrate indirect (or non-line-of-sight) communication paths between TRP 305 or TRP 310 and UE 115-b (such that signaling via an indirect communication path can reflect off one or more objects). Figure 3 As shown, solid lines can illustrate direct communication paths between TRP 305 or TRP 310 and UE 115-b, and dashed lines can illustrate indirect (or non-line-of-sight) communication paths between TRP 305 or TRP 310 and UE 115-b (such that signaling via an indirect communication path can reflect off one or more objects).

[0124] In some examples, the UE 115-b can receive an indication of DOFs of the antenna panels 315 of the TRP 305 and the DOFs of the antenna panels 325 of the TRP 310 from one or both of the TRP 305 or the TRP 310. The UE 115-b can determine whether to select to communicate with one or both of the TRP 305 or the TRP 310 based on a first difference between a first DOF of the antenna panels 315 of the TRP 305 and a DOF of a corresponding antenna module 350 of the UE 115-b (an antenna module 350 of the UE 115-b that can receive the beams 335 from the antenna panels 315 of the TRP 305) and a second difference between a second DOF of the antenna panels 325 of the TRP 310 and a DOF of the corresponding antenna module 350 of the UE 115-b (an antenna module 350 of the UE 115-b that can receive the beams 340 from the antenna panels 325 of the TRP 310). For example, in examples where the UE 115-b determines that the first difference and the second difference are within a threshold difference or less than a threshold difference (which can be referred to herein as a threshold DOF mismatch), the UE 115-b can determine to establish a connection with the TRP 305 and with the TRP 310.

[0125] Based on determining to establish connections with TRP 304 and TRP 330 according to the DOF mismatch between UE 115-b and each of TRP 305 and TRP 310, UE 115-b can receive one or more downlink reference signals (such as SSBs or CSI-RSs, among other examples) from each of TRP 305 or TRP 310 as part of a beam sweeping or beam training procedure. For example, TRP 305 can transmit one or more SSBs on various beams 335 from antenna panel 315, and TRP 310 can transmit one or more SSBs on various beams 340 from antenna panel 325, and UE 115-b can monitor for the SSBs from TRP 305 and TRP 310 based on monitoring on various beams 345 from one or more of antenna modules 350 of UE 115-b. In some examples, UE 115-b can identify a beam direction based on an SSB index included in each of the SSBs, and can determine which of TRP 305 or TRP 310 transmitted the SSB based on a cell ID that UE 115-b can determine based on MIB, SIB1, and SIB2 included in the received SSB. Thus, UE 115-b can identify which beams TRP 305 and TRP 310 can use to communicate with UE 115-b, and UE 115-b can identify which beams 345 to use to communicate with TRP 305 or TRP 310. Additionally, in some examples, UE 115-b can identify which beams to use for communications between UE 115-b, TRP 305, and TRP 310 based on an out-of-band emission threshold. In some aspects, UE 115-b can determine to use beam 345-a to communicate with TRP 310, and to use beam 345-c to communicate with TRP 305.

[0126] The UE 115-b can transmit beam selection signaling to one or both of the TRP 305 or the TRP 310, which includes an indication of beams identified by the UE 115-b that the TRP 305 and the TRP 310 can use to communicate with the UE 115-b. Additionally or alternatively, the UE 115-b can transmit, within the beam selection signaling, an indication of beams 345 (such as the beam 345-a and the beam 345-c) selected by the UE 115-b for use in communicating with the TRP 305 and the TRP 310. In some implementations, the UE 115-b can transmit, within the beam selection signaling or in signaling separate from the beam selection signaling, an indication of a DOF mismatch between an antenna module 350 of the UE 115-b and an antenna panel of a TRP with which the UE 115-b uses the antenna module 350 to communicate. For example, in an example in which the UE 115-b uses the antenna module 350-a of the UE 115-b to communicate with the antenna panel 315 of the TRP 305, the UE 115-b can transmit an indication of a DOF mismatch (a measured difference in DOF) between the antenna panel 315 and the antenna module 350-a. Similarly, in an example in which the UE 115-b uses the antenna module 350-b of the UE 115-b to communicate with the antenna panel 325 of the TRP 310, the UE 115-b can transmit an indication of a DOF mismatch (a measured difference in DOF) between the antenna panel 325 and the antenna module 350-b.

[0127] Figure 4 An example of a process flow 400 that supports techniques for indicating beams in a multi-TRP system based on DOF mismatch is shown. The process flow 400 illustrates Figures 1-3 communications between a UE 115-c, a TRP 405, and a TRP 410, which can be examples of the corresponding devices described herein. For example, the UE 115-c can be an example of a UE 115, UE 115-a, or UE 115-b as described with reference to Figure 1 described with reference to Figure 2 described with reference to Figure 3The example TRPs 305 or 310 are described. The TRP 405 and the TRP 410 can operate on different radio frequency spectrum bands, or can operate on the same radio frequency spectrum band. In some examples, the UE 115-c can select to communicate with one or both of the TRP 405 or the TRP 410 based on a DOF mismatch between the antenna ports of the TRP and the antenna modules of the UE 115-c, and the UE 115-c can also indicate which beams the selected TRP can use to communicate with the UE 115-c based on the DOF mismatch.

[0128] At 415, the TRP 405 can transmit a control message to the UE 115-c indicating a first set of DOFs for a first set of ports associated with the TRP 405 and indicating a second set of DOFs for a second set of ports associated with the TRP 410. For example, the control message can indicate a DOF for each of the ports of the TRP 405 (if not all of the ports) and a DOF for each of the ports of the TRP 410 (if not all of the ports).

[0129] At 420, the UE 115-c can select one or both of the TRP 405 or the TRP 410 based on a DOF mismatch between one or more DOFs supported at the UE 115-c and the first set of DOFs supported at the TRP 405, and a DOF mismatch between the one or more DOFs supported at the UE 115-c and the second set of DOFs supported at the TRP 410. Additional details related to such selection of a TRP to connect to based on a DOF mismatch are described herein (including with reference to Figure 2 and 3 ).

[0130] At 425, in some implementations, the TRP 405 can transmit a number of downlink reference signals (such as SSBs or CSI-RSs, among other examples) via a number of beams from each antenna panel or each port of the TRP 405. Similarly, at 430, in some implementations, the TRP 410 can transmit a number of downlink reference signals via a number of beams from each antenna panel or each port of the TRP 410. In some examples, the TRP 405 and the TRP 410 can transmit their respective number of downlink reference signals as part of a beam training procedure, such as a beam training procedure in a synchronization or access procedure.

[0131] Additionally or alternatively, at 435, in some implementations, UE 115-c can transmit a number of uplink reference signals (such as SRS) to TRP 405. Similarly, at 440, in some implementations, UE 115-c can transmit a number of uplink reference signals to TRP 410. In some examples, UE 115-c can transmit a number of uplink reference signals to TRP 405 and TRP 410 as part of a beam training procedure, such as a beam training procedure within a synchronization or access procedure.

[0132] At 445, UE 115-c can select or otherwise determine which beams to use for communication with the selected TRPs. For example, in examples where UE 115-c determines to connect with both TRP 405 and TRP 410 (such that both TRP 405 and TRP 410 support DOFs within the threshold DOF mismatch for DOFs supported by UE 115-c), UE 115-c can select which beams TRP 405 and TRP 410 can use to communicate with UE 115-c based on the number of downlink reference signals received from each TRP. Additional details related to selection of beams that TRP 405 or TRP 410 can use to communicate with UE 115-c are described herein, including with reference to Figure 3 ).

[0133] At 450, UE 115-c can transmit or receive beam selection signaling from TRP 405 that indicates a selection of TRP 405 and TRP 410 for communication with the UE (indicating that TRP 405 or TRP 410 can communicate with UE 115-c) and indicates at least one beam associated with a port for each TRP. For example, in addition to including an indication of a selection of which TRPs UE 115-c can communicate with based on a DOF mismatch, the beam selection signaling can indicate at least a first beam associated with a first port of a first set of ports associated with TRP 405 and at least a second beam associated with a second port of a second set of ports associated with TRP 410. Thus, the beam selection signaling can indicate that TRP 405 can use the first beam to communicate with UE 115-c and that TRP 410 can use the second beam to communicate with UE 115-c.

[0134] In some implementations, UE 115-c or TRP 405 can indicate the first beam associated with the first port and the second beam associated with the second port based on determining that the first DOF of the first port is within a threshold DOF mismatch of the one or more DOFs of UE 115-c and the second DOF of the second port is within the threshold DOF mismatch of the one or more DOFs of UE 115-c. In examples where UE 115-c receives downlink reference signals from TRP 405 and TRP 410 at 425 and 430, respectively, UE 115-c can transmit beam selection signaling to TRP 405. In examples where UE 115-c transmits uplink reference signals to TRP 405 and TRP 410 at 435 and 440, respectively, UE 115-c can receive beam selection signaling from TRP 405.

[0135] At 455, UE 115-c, TRP 405, and TRP 410 can transmit or receive a multi-TRP transmission. Such joint / multi-TRP transmission can refer to simultaneous transmission of the same signal or message (such as an SDM transmission). In some examples, for example, TRP 405 and TRP 410 can transmit a joint / multi-TRP transmission (e.g., can transmit according to a multi-TRP communication scheme) and UE 115-c can receive the joint / multi-TRP transmission. In such examples, TRP 405 can transmit a first instance of the multi-TRP transmission to UE 115-c at 455-a and TRP 410 can transmit a second instance of the multi-TRP transmission to UE 115-c at 455-b (where 455-a and 455-b can be contemporaneous in time). In some other examples, UE 115-c can transmit a joint / multi-TRP transmission to TRP 405 and TRP 410. In such examples, UE 115-c can transmit a first instance of the multi-TRP transmission to TRP 405 at 455-a and UE 115-c can transmit a second instance of the multi-TRP transmission to TRP 410 at 455-b (where 445-a and 455-b can be contemporaneous in time).

[0136] Figure 5A block diagram 500 of an example device 505 that supports techniques for indicating beams in multi-TRP systems based on DOF mismatch is shown. The device 505 can wirelessly communicate with one or more base stations 105, UEs 115, or any combination thereof. The device 505 can include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 520, an input / output (I / O) controller 510, a transceiver 515, an antenna 525, a memory 530, code 535, and a processor 540. These components can be in electronic communication or otherwise coupled via one or more buses (e.g., bus 545) for inter-component communication.

[0137] The communications manager 520 can support wireless communication at a UE in accordance with examples as disclosed herein. The communications manager 520 can be configured as or otherwise support a means for receiving a control message indicating a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP. In some examples, the communications manager 520 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0138] In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communications manager 520 can be configured as or otherwise support a means for transmitting or receiving an indication of a first beam associated with a first port and a second beam associated with a second port based on a first mismatch between a first DOF associated with the first port and a DOF of the UE being within a threshold mismatch and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within the threshold mismatch. In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communications manager 520 can be configured as or otherwise support a means for transmitting or receiving an indication of a first mismatch between a first DOF associated with a first port and a DOF of the UE and a second mismatch between a second DOF associated with a second port and the DOF of the UE.

[0139] In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communications manager 520 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling indicating a pair of receive beams of the UE for receiving multi-TRP transmissions from the first TRP and the second TRP. In some examples, the communications manager 520 can be configured as or otherwise support a means for receiving the multi-TRP transmissions from the first TRP and the second TRP via the pair of receive beams of the UE.

[0140] In some examples, to support receiving multi-TRP transmissions from the first TRP and the second TRP, the communications manager 520 can be configured as or otherwise support a means for receiving the multi-TRP transmissions from the first TRP via at least a first beam on a first frequency band and from the second TRP via at least a second beam on a second frequency band, where the first frequency band and the second frequency band comprise a super wideband frequency band. In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communications manager 520 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling indicating a pair of transmit beams of the UE for transmitting multi-TRP transmissions to the first TRP and the second TRP.

[0141] In some examples, the communications manager 520 can be configured as or otherwise support a means for transmitting the multi-TRP transmissions to the first TRP via a first transmit beam of the pair of transmit beams and to the second TRP via a second transmit beam of the pair of transmit beams. In some examples, the communications manager 520 can be configured as or otherwise support a means for receiving a first one or more downlink reference signals from the first TRP via a first one or more ports of a first port set and a second one or more downlink reference signals from the second TRP via a second one or more ports of a second port set, where the beam selection signaling is based on the first one or more downlink reference signals and the second one or more downlink reference signals.

[0142] In some examples, the communication manager 520 can be configured as or otherwise support a means for transmitting a first one or more uplink reference signals to a first TRP and a second one or more uplink reference signals to a second TRP, where the beam selection signaling is based on the first one or more uplink reference signals and the second one or more uplink reference signals. In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 520 can be configured as or otherwise support a means for transmitting or receiving an indication of a first beam associated with a first port and a second beam associated with a second port based on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emissions.

[0143] The I / O controller 510 can manage input and output signals for the device 505. The I / O controller 510 can also manage peripherals not integrated into the device 505. In some examples, the I / O controller 510 can represent a physical connection or port to the operating system such as iOS®, ANDROID®, MS-DOS®, MS-WINDOWS®, OS / 2®, LINUX®, UNIX® or another known operating system, or another type of operating system. Additionally or alternatively, the I / O controller 510 can represent a modem, a keyboard, a mouse, a touchscreen, or a similar device, or an interface for such devices. In some examples, the I / O controller 510 can be implemented as part of a processor, such as the processor 540. In some examples, a user can interact with the device 505 via the I / O controller 510 or via hardware components controlled by the I / O controller 510.

[0144] In some examples, the device 505 can include a single antenna 525. However, in some other examples, the device 505 can have more than one antenna 525, which can be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 515 can communicate bi-directionally, via the one or more antennas 525, wired, or wireless links as described herein. For example, the transceiver 515 can represent a wireless transceiver and can communicate bi-directionally with another wireless transceiver. The transceiver 515 can also include a modem to modulate the packets, to provide the modulated packets to the one or more antennas 525 for transmission, and to demodulate packets received from the one or more antennas 525.

[0145] Memory 530 can include random access memory (RAM) and read-only memory (ROM). The memory 530 can store computer-readable, computer-executable code 535 including instructions that, when executed by the processor 540, cause the device 505 to perform various functions described herein. The code 535 can be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some examples, the code 535 can not be directly executable by the processor 540 but can cause a computer (e.g., when compiled and executed) to perform functions described herein. In some examples, the memory 530 can include, among other things, a basic I / O system (BIOS), which can control basic hardware or software operation such as the interaction with peripheral components or devices.

[0146] In some implementations, the processor 540 can be a component of a processing system. A processing system can generally refer to a system or series of machines or components that receive input and process the input to produce a set of outputs (which can be passed to other systems or components of, for example, a UE 115). For example, a processing system of a UE 115 can refer to a system that includes various other components or subcomponents of the UE 115.

[0147] A processing system of a UE 115 can interface with other components of the UE 115 and can process information received or obtained from the other components (such as input or signals) and output information to the other components. For example, a chip or modem of a UE 115 can include a processing system, a first interface to receive or obtain information, and a second interface to output, send, or provide information. In some implementations, the first interface can refer to an interface between the processing system of the chip or modem and a receiver, such that the UE 115 can receive information or signal input and can pass the information to the processing system. In some implementations, the second interface can refer to an interface between the processing system of the chip or modem and a transmitter, such that the UE 115 can send information output from the chip or modem. One of ordinary skill in the art would readily recognize that the second interface can also or instead obtain or receive information or signal input, and the first interface can also or instead output, send, or provide information.

[0148] In some examples, the communication manager 520 can be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 515, the one or more antennas 525, or any combination thereof. Although the communication manager 520 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 520 can be supported by, or performed by, the processor 540, the memory 530, the code 535, or any combination thereof. For example, the code 535 can include instructions executable by the processor 540 to cause the device 505 to perform various aspects of techniques for indicating beams in multi-TRP systems based on DOF mismatch as described herein, or the processor 540 and the memory 530 can be otherwise configured to support or perform such operations.

[0149] Figure 6 A diagram of a system 600 including a device 605 that supports techniques for indicating beams in multi-TRP systems based on DOF mismatch is shown. The device 605 can wirelessly communicate with one or more base stations 105, UEs 115, or any combination thereof. The device 605 can include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communication manager 620, a network communications manager 610, a transceiver 615, an antenna 625, a memory 630, a code 635, a processor 640, and an inter-station communications manager 645. These components can be in electronic communication or otherwise

[0150] The communication manager 620 can support wireless communication at a first TRP in accordance with examples as disclosed herein. The communication manager 620 can be configured as or otherwise support a means for transmitting, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP. In some examples, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving, based on the control message, beam selection signaling indicating a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0151] In some examples, and to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving an indication of a first beam associated with a first port and a second beam associated with a second port based on a first mismatch between a first DOF associated with the first port and a DOF of the UE being within a threshold mismatch and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within the threshold mismatch. In some examples, and to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving an indication of a first mismatch between a first DOF associated with a first port and a DOF of the UE and a second mismatch between a second DOF associated with a second port and the DOF of the UE.

[0152] In some examples, and to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling indicating a pair of receive beams of the UE for receiving multi-TRP transmissions from the first TRP and the second TRP. In some examples, the communication manager 620 can be configured as or otherwise support a means for transmitting, to the UE, a multi-TRP transmission via a receive beam of the pair of receive beams at the UE using at least a first beam associated with a first port and jointly with the second TRP.

[0153] In some examples, and to support transmitting multi-TRP transmissions to the UE, the communication manager 620 can be configured as or otherwise support a means for transmitting the multi-TRP transmissions on a first frequency band, the first frequency band being different from a second frequency band on which the second TRP transmits the multi-TRP transmissions, where the first frequency band and the second frequency band comprise a super wideband frequency band. In some examples, and to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling indicating a pair of transmit beams of the UE for transmitting multi-TRP transmissions to the first TRP and the second TRP.

[0154] In some examples, the communication manager 620 can be configured as or otherwise support a means for receiving, from the UE, a multi-TRP transmission via a transmit beam of a pair of transmit beams of the UE using at least a first beam associated with a first port. In some examples, the communication manager 620 can be configured as or otherwise support a means for transmitting one or more downlink reference signals via one or more ports of a first set of ports, where the beam selection signaling is based on the one or more downlink reference signals.

[0155] In some examples, the communication manager 620 can be configured as or otherwise support a means for receiving one or more uplink reference signals from a UE at one or more ports of the first set of ports, where the beam selection signaling is based on the one or more uplink reference signals. In some examples, to support transmitting or receiving beam selection signaling for multi-TRP transmissions, the communication manager 620 can be configured as or otherwise support a means for transmitting or receiving an indication of a first beam associated with the first port and a second beam associated with the second port based on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emissions.

[0156] The network communications manager 610 can manage communications with the core network 130 (e.g., via one or more wired backhaul links). For example, the network communications manager 610 can manage the transfer of data communications for client devices, such as one or more UEs 115.

[0157] In some examples, the device 605 can include a single antenna 625. In some other examples, the device 605 can have more than one antenna 625, which can be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 615 can communicate bi-directionally, via the one or more antennas 625, wired, or wireless links as described herein. For example, the transceiver 615 can represent a wireless transceiver and can communicate bi-directionally with another wireless transceiver. The transceiver 615 can also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 625 for transmission, and to demodulate packets received from one or more antennas 625.

[0158] The memory 630 can include RAM and ROM. The memory 630 can store computer-readable, computer-executable code 635 including instructions that, when executed by the processor 640, cause the device 605 to perform various functions described herein. The code 635 can be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some examples, the code 635 can not be directly executable by the processor 640 but can cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the memory 630 can contain, among other things, a BIOS which can control basic hardware or software operation such as the interaction with peripheral components or devices.

[0159] In some implementations, the processor 740 can be a component of a processing system. A processing system can generally refer to a system or series of machines or components that receives inputs and processes the inputs to produce a set of outputs (which can be passed to other systems or components, e.g., of a TRP or base station 105). For example, a processing system of a base station 105 can refer to a system that includes various other components or subcomponents of a TRP or base station 105.

[0160] A processing system of a TRP can interface with other components of the TRP and can process information (such as inputs or signals) received from the other components and output information to the other components. For example, a chip or modem of a TRP can include a processing system, a first interface to receive or obtain information, and a second interface to output, send, or provide information. In some implementations, the first interface can refer to an interface between the processing system of the chip or modem and a receiver, such that the TRP can receive information or signal inputs and can pass the information to the processing system. In some implementations, the second interface can refer to an interface between the processing system of the chip or modem and a transmitter, such that the TRP can send information output from the chip or modem. One of ordinary skill in the art will readily recognize that the second interface can also or instead obtain or receive information or signal inputs, and the first interface can also or instead output, send, or provide information.

[0161] The inter-station communications manager 645 can manage communications with other base station 105 and can include a controller or scheduler for controlling communications with UEs 115 in cooperation with other base stations 105. For example, the inter-station communications manager 645 can coordinate scheduling for transmissions to UEs 115 for various interference mitigation techniques such as beamforming or joint transmission. In some examples, the inter-station communications manager 645 can provide an X2 interface within an LTE / LTE-A wireless communication network technology to provide communication between base stations 105.

[0162] The communications manager 620 can support wireless communication at a first TRP in accordance with examples as disclosed herein. For example, the communications manager 620 can be configured as or otherwise support a means for transmitting a control message to a UE, the control message indicating a first set of DOFs for a first set of ports associated with the first TRP and a second set of DOFs for a second set of ports associated with a second TRP. The communications manager 620 can be configured as or otherwise support a means for transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0163] In some examples, the communication manager 620 can be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or in cooperation with the transceiver 615, the one or more antennas 625, or any combination thereof. Although the communication manager 620 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 620 can be supported by or performed by the processor 640, the memory 630, the code 635, or any combination thereof. For example, the code 635 can include instructions executable by the processor 640 to cause the device 605 to perform various aspects of techniques for indicating beams in multi-TRP systems based on DOF mismatch as described herein, or the processor 640 and the memory 630 can be otherwise configured to perform or support performance of such operations.

[0164] Figure 7 A flow diagram illustrating a method 700 that supports techniques for indicating beams in multi-TRP point systems based on DOF mismatch is shown. The operations of method 700 can be implemented by a UE or its components as described herein. For example, the operations of method 700 can be performed by a UE 115 as described with reference to FIGs. 1-2, 4, and 5. In some examples, a UE can execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE can perform aspects of the described functions using special-purpose hardware. Figures 1-5 Described techniques can be implemented in hardware, software, or a combination of both. Such technology can be implemented within one or more components of a device, such as a UE 115. The components can be configured to perform and / or support performance of the described techniques in hardware, software, or a combination of both. For example, a component can include one or more processors configured to perform a software- based implementation of the described techniques, and / or the component can include one or more hardware logic components configured to perform an hardware-based implementation of the described techniques.

[0165] At 705, the method can include receiving a control message indicating a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP. The operations of 705 can be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 705 can be performed by a communication manager as described with reference to Figure 5 FIG. 4 through FIG. 5.

[0166] At 710, the method can include transmitting or receiving beam selection signaling based on the control message, where the beam selection signaling indicates a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports. The operations of 710 can be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 710 can be performed by a communication manager as described with reference to Figure 5 FIG. 4 through FIG. 5.

[0167] Figure 8A flowchart illustrating a method 800 that supports techniques for indicating beams in multi-TRP point systems based on DOF mismatch is shown. The operations of method 800 can be implemented by a TRP or base station or its components as described herein. For example, the operations of method 800 can be performed by a base station 105 as described with reference to Figures 1-4 FIGs. 1 through 6. In some examples, a base station can execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station can perform aspects of the described functions using special-purpose hardware.

[0168] At 805, the method can include transmitting, to a UE, a control message indicating a first set of DOFs for a first set of ports associated with a first TRP and a second set of DOFs for a second set of ports associated with a second TRP. The operations of 805 can be performed according to the examples as disclosed herein. In some examples, aspects of the operations of 805 can be performed by a communication manager as described with reference to Figure 6 FIGs. 1 through 6. In some examples, a base station can execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station can perform aspects of the described functions using special-purpose hardware.

[0169] At 810, the method can include transmitting or receiving, based on the control message, beam selection signaling indicating a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports. The operations of 810 can be performed according to the examples as disclosed herein. In some examples, aspects of the operations of 810 can be performed by a communication manager as described with reference to Figure 6 FIGs. 1 through 6. In some examples, a base station can execute a set of instructions to control the functional elements of the base station to perform the described functions. Additionally or alternatively, the base station can perform aspects of the described functions using special-purpose hardware.

[0170] Summaries of some aspects of the disclosure are provided below:

[0171] Aspect 1 : A method for wireless communication at a UE, comprising: receiving a control message indicating: a first set of DOFs for a first set of ports associated with a first TRP, and a second set of DOFs for a second set of ports associated with a second TRP; and transmitting or receiving, based at least in part on the control message, beam selection signaling indicating: a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0172] Aspect 2: The method of aspect 1, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on a first mismatch between a first DOF associated with the first port and a DOF of the UE being within a threshold mismatch and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within the threshold mismatch.

[0173] Aspect 3: The method of any of aspects 1 through 2, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of a first mismatch between a first DOF associated with the first port and a DOF of the UE and a second mismatch between a second DOF associated with the second port and the DOF of the UE.

[0174] Aspect 4: The method of any of aspects 1 through 3, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the beam selection signaling indicating a pair of receive beams of the UE for receiving a multi-TRP transmission from the first TRP and the second TRP.

[0175] Aspect 5: The method of aspect 4, further comprising: receiving the multi-TRP transmission from the first TRP and the second TRP via the pair of receive beams of the UE.

[0176] Aspect 6: The method of aspect 5, wherein receiving the multi-TRP transmission from the first TRP and the second TRP comprises: receiving the multi-TRP transmission from the first TRP via at least the first beam on a first frequency band and from the second TRP via at least the second beam on a second frequency band, wherein the first frequency band and the second frequency band comprise an ultra-wideband frequency band.

[0177] Aspect 7: The method of any of aspects 1 through 6, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the beam selection signaling indicating a pair of transmit beams of the UE for transmitting a multi-TRP transmission to the first TRP and the second TRP.

[0178] Aspect 8: The method of aspect 7, further comprising: transmitting the multi-TRP transmission to the first TRP via a first transmit beam of the pair of transmit beams and to the second TRP via a second transmit beam of the pair of transmit beams.

[0179] Aspect 9: The method of any of aspects 1 through 8, further comprising: receiving, via a first one or more ports of the first set of ports, a first one or more downlink reference signals from the first TRP and receiving, via a second one or more ports of the second set of ports, a second one or more downlink reference signals from the second TRP, wherein the beam selection signaling is based at least in part on the first one or more downlink reference signals and the second one or more downlink reference signals.

[0180] Aspect 10: The method of any of aspects 1 through 9, further comprising: transmitting, to the first TRP, a first one or more uplink reference signals and transmitting, to the second TRP, a second one or more uplink reference signals, wherein the beam selection signaling is based at least in part on the first one or more uplink reference signals and the second one or more uplink reference signals.

[0181] Aspect 11: The method of any of aspects 1 through 10, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emissions.

[0182] Aspect 12: A method for wireless communications at a first TRP, comprising: transmitting, to a UE, a control message indicating: a first set of DOFs for a first set of ports associated with the first TRP, and a second set of DOFs for a second set of ports associated with a second TRP; and transmitting or receiving, based at least in part on the control message, beam selection signaling, wherein the beam selection signaling indicates: a selection of the first TRP and the second TRP for communications with the UE, at least a first beam associated with a first port of the first set of ports, and at least a second beam associated with a second port of the second set of ports.

[0183] Aspect 13: The method of aspect 12, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on a first mismatch between a first DOF associated with the first port and a DOF of the UE being within a threshold mismatch and a second mismatch between a second DOF associated with the second port and the DOF of the UE being within the threshold mismatch.

[0184] Aspect 14: The method of any of aspects 12 through 13, wherein transmitting or receiving the beam selection signaling further comprises transmitting or receiving an indication of a first mismatch between a first DOF associated with the first port and a DOF of the UE and a second mismatch between a second DOF associated with the second port and the DOF of the UE.

[0185] Aspect 15: The method of any of aspects 12 through 14, wherein transmitting or receiving the beam selection signaling further comprises transmitting or receiving the beam selection signaling indicating a pair of receive beams of the UE for receiving a multi-TRP transmission from the first TRP and the second TRP.

[0186] Aspect 16: The method of aspect 15, further comprising outputting, to the UE, the multi-TRP transmission via a receive beam of the pair of receive beams at the UE, using at least the first beam associated with the first port and jointly with the second TRP.

[0187] Aspect 17: The method of aspect 16, wherein transmitting the multi-TRP transmission to the UE comprises transmitting the multi-TRP transmission on a first frequency band that is different from a second frequency band on which the second TRP transmits the multi-TRP transmission, wherein the first frequency band and the second frequency band comprise an ultra-wideband frequency band.

[0188] Aspect 18: The method of any of aspects 12 through 17, wherein transmitting or receiving the beam selection signaling further comprises transmitting or receiving the beam selection signaling indicating a pair of transmit beams of the UE for transmitting a multi-TRP transmission to the first TRP and the second TRP.

[0189] Aspect 19: The method of aspect 18, further comprising receiving, from the UE, the multi-TRP transmission via a transmit beam of the pair of transmit beams of the UE, using at least the first beam associated with the first port.

[0190] Aspect 20: The method of any of aspects 12 through 19, further comprising transmitting one or more downlink reference signals via one or more ports of the set of first ports, wherein the beam selection signaling is based at least in part on the one or more downlink reference signals.

[0191] Aspect 21: The method of any of aspects 12 through 20, further comprising: receiving one or more uplink reference signals from the UE at one or more ports of the first set of ports, wherein the beam selection signaling is based at least in part on the one or more uplink reference signals.

[0192] Aspect 22: The method of any of aspects 12 through 21, wherein transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emissions.

[0193] Aspect 23: An apparatus for wireless communication at a UE, comprising at least a first interface, a processing system, and a second interface, configured to cause the apparatus to perform the method of any of aspects 1 through 11.

[0194] Aspect 24: An apparatus for wireless communication at a UE, comprising a processor; a memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of any of aspects 1 through 11.

[0195] Aspect 25: An apparatus for wireless communication at a UE, comprising at least one means for performing the method of any of aspects 1 through 11.

[0196] Aspect 26: A non-transitory computer-readable medium storing code for wireless communication at a UE, the code comprising instructions executable by a processor to perform the method of any of aspects 1 through 11.

[0197] Aspect 27: An apparatus for wireless communication at a first TRP, comprising at least a first interface, a processing system, and a second interface, configured to cause the apparatus to perform the method of any of aspects 12 through 22.

[0198] Aspect 28: An apparatus for wireless communication at a first TRP, comprising a processor; a memory coupled with the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform the method of any of aspects 12 through 22.

[0199] Aspect 29: An apparatus for wireless communication at a first TRP, comprising at least one means for performing the method of any of aspects 12 through 22.

[0200] Aspect 30: A non-transitory computer-readable medium storing code for wireless communication at a first TRP, the code comprising instructions executable by a processor to perform the method of any of aspects 12 through 22.

[0201] As used herein, a phrase referring to “at least one of’ a list of items refers to any combination of those items, including single members. As an example, “at least one of a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c.

[0202] The various illustrative logics, logical blocks, modules, circuits and algorithm processes described in connection with the implementations disclosed herein can be implemented as electronic hardware, computer software, or combinations of both. The interchangeability of hardware and software has been described generally, in terms of

[0203] The hardware and data processing apparatus used to implement the various illustrative logics, logical blocks, modules and circuits described in connection with the aspects disclosed herein can be implemented or performed with a general purpose single- or multi-chip processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general purpose processor can be a microprocessor, or any conventional processor, controller, microcontroller, or state machine. A processor also can be implemented as a combination of

[0204] In one or more aspects, the functions described can be implemented in hardware, digital electronic circuitry, computer software, firmware, including the structures disclosed in this specification and their structural equivalents, or in any combination thereof. Implementations of the subject matter described in this specification also can be implemented as one or more computer programs, e.g., one or more modules of computer program instructions, encoded on a computer storage media for execution by, or to control the operation of, data processing apparatus.

[0205] If implemented in software, the functions can be stored or transmitted over as one or more instructions or code on a computer-readable medium. Computer-readable media include both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. A storage medium can be any available medium that can be accessed by a computer. By way of example, and not limitation, such computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other medium that can be used to carry or store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection is properly termed a computer-readable medium. Disk and disc, as used herein, includes compact disc (CD), laser disc, optical disc, digital versatile disc (DVD), floppy disk, and blu-ray disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Combinations of the above should also be included within the scope of computer-readable media.

[0206] Various modifications to these implementations described in this disclosure will be readily apparent to those skilled in the art, and the generic principles defined herein can be applied to other implementations without departing from the spirit or scope of this disclosure. Thus, the claims are not intended to be limited to the implementations shown herein, but are to be accorded the widest scope consistent with this disclosure, the principles and the features disclosed herein.

[0207] Additionally, those skilled in the art will readily recognize that the terms "upper" and "lower" are sometimes used for ease of description in relation to the drawings and indicate relative positions on a properly oriented page corresponding to the orientation of the drawings, and can not reflect the proper orientation of any device as implemented.

[0208] Certain features described in this specification in the context of separate implementations can also be implemented in combination in a single implementation. Conversely, various features described in the context of a single implementation can also be implemented separately or in any suitable subcombination. Moreover, although features can be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination and the claimed combination can be directed to a subcombination or variation of a subcombination.

[0209] Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring such an order nor that all illustrated operations be performed to achieve desirable results. Further, the drawings can schematically depict one more example processes in the form of a flowchart or flow diagram. However, other operations that are not depicted can be incorporated in the example processes that are schematically illustrated. For example, one or more additional operations can be performed before, after, simultaneously with, or between any or more of the illustrated operations. In certain circumstances, multitasking and parallel processing can be advantageous. Moreover, the separation of various system components in the implementations described above should not be understood as requiring such separation in all implementations, and it should be understood that the described program components and systems can generally be integrated in a single software product or packaged into multiple software products. Additionally, other implementations are within the scope of the following claims. In some examples, the actions recited in the claims can be performed in a different order and still achieve desirable results.

Claims

1. An apparatus for wireless communication at a user equipment (UE), comprising: a first interface configured to: obtain a control message that indicates: a first set of default operating frequencies for a first set of ports associated with a first transmission and reception point (TRP), and a second set of default operating frequencies for a second set of ports associated with a second TRP; and the first interface or a second interface configured to: output or obtain, based at least in part on the control message, beam selection signaling that indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, an indication of the first beam being associated with a first mismatch between a first default operating frequency of the first port and a default operating frequency of the UE, and at least a second beam associated with a second port of the second set of ports, an indication of the second beam being associated with a second mismatch between a second default operating frequency of the second port and the default operating frequency of the UE.

2. The apparatus of claim 1, wherein, outputting or obtaining the beam selection signaling further comprises: outputting or obtaining the indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE being within a threshold mismatch and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE being within the threshold mismatch.

3. The apparatus of claim 1, wherein, outputting or obtaining the beam selection signaling further comprises: outputting or obtaining an indication of the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE.

4. The apparatus of claim 1, wherein, outputting or obtaining the beam selection signaling further comprises: outputting or obtaining the beam selection signaling indicating a pair of receive beams of the UE for obtaining a multi-TRP transmission from the first TRP and the second TRP.

5. The apparatus of claim 4, wherein, the first interface or the second interface is further configured to: obtain the multi-TRP transmission from the first TRP and the second TRP via the pair of receive beams of the UE.

6. The apparatus of claim 5, wherein, obtaining the multi-TRP transmission from the first TRP and the second TRP further comprises: obtaining the multi-TRP transmission from the first TRP via at least the first beam on a first frequency band and from the second TRP via at least the second beam on a second frequency band, wherein the first frequency band and the second frequency band comprise an ultra-wideband frequency band.

7. The apparatus of claim 1, wherein, outputting or obtaining the beam selection signaling further comprises: outputting or obtaining the beam selection signaling indicating a pair of transmit beams of the UE for outputting a multi-TRP transmission to the first TRP and the second TRP.

8. The apparatus of claim 7, wherein, The first interface or the second interface is further configured to: output the multi-TRP transmission to the first TRP via a first transmit beam of the pair of transmit beams and to the second TRP via a second transmit beam of the pair of transmit beams.

9. The apparatus of claim 1, wherein, The first interface or the second interface is further configured to: obtain: a first one or more downlink reference signals from the first TRP via a first one or more ports of the first set of ports, and a second one or more downlink reference signals from the second TRP via a second one or more ports of the second set of ports, wherein the beam selection signaling is based at least in part on the first one or more downlink reference signals and the second one or more downlink reference signals.

10. The apparatus of claim 1, wherein, The first interface or the second interface is further configured to: output: a first one or more uplink reference signals to the first TRP; and a second one or more uplink reference signals to the second TRP, wherein the beam selection signaling is based at least in part on the first one or more uplink reference signals and the second one or more uplink reference signals.

11. The apparatus of claim 1, wherein, Outputting or obtaining the beam selection signaling further comprises: outputting or obtaining an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold with respect to out-of-band emissions.

12. An apparatus for wireless communication at a first transmission and reception point (TRP), comprising: a first interface configured to: output, to a user equipment (UE), a control message, the control message indicating: a first set of default operating frequencies for a first set of ports associated with the first TRP, and a second set of default operating frequencies for a second set of ports associated with a second TRP; and the first interface or second interface configured to: output or obtain, based at least in part on the control message, beam selection signaling, wherein the beam selection signaling indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, the indication of the first beam being associated with a first mismatch between a first default operating frequency of the first port and a default operating frequency of the UE, and at least a second beam associated with a second port of the second set of ports, the indication of the second beam being associated with a second mismatch between a second default operating frequency of the second port and the default operating frequency of the UE.

13. The apparatus of claim 12, wherein, Outputting or obtaining the beam selection signaling further comprises: output or obtain an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE being within a threshold mismatch.

14. The apparatus of claim 12, wherein, Outputting or obtaining the beam selection signaling further includes: outputting or obtaining an indication of the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE.

15. The apparatus of claim 12, wherein, Outputting or obtaining the beam selection signaling further includes: outputting or obtaining the beam selection signaling indicating a pair of receive beams of the UE for obtaining a multi-TRP transmission from the first TRP and the second TRP.

16. The apparatus of claim 15, wherein, the first interface or the second interface is further configured to: output, to the UE, the multi-TRP transmission via a transmit beam of the pair of transmit beams of the UE using at least the first beam associated with the first port.

17. The apparatus of claim 16, wherein, Outputting the multi-TRP transmission to the UE further includes: outputting the multi-TRP transmission on a first frequency band that is different from a second frequency band on which the second TRP transmits the multi-TRP transmission, wherein the first frequency band and the second frequency band comprise an ultra-wideband frequency band.

18. The apparatus of claim 12, wherein, Outputting or obtaining the beam selection signaling further includes: outputting or obtaining the beam selection signaling indicating a pair of transmit beams of the UE for outputting a multi-TRP transmission to the first TRP and the second TRP.

19. The apparatus of claim 18, wherein, the first interface or the second interface is further configured to: obtain, from the UE, the multi-TRP transmission via a transmit beam of the pair of transmit beams of the UE using at least the first beam associated with the first port.

20. The apparatus of claim 12, wherein, the first interface or the second interface is further configured to: output: one or more downlink reference signals via one or more ports of the first set of ports, wherein the beam selection signaling is based at least in part on the one or more downlink reference signals.

21. The apparatus of claim 12, wherein, the first interface or the second interface is further configured to: obtain: one or more uplink reference signals from the UE at one or more ports of the first set of ports, wherein the beam selection signaling is based at least in part on the one or more uplink reference signals.

22. The apparatus of claim 12, wherein, Outputting or obtaining the beam selection signaling further includes: output or obtain an indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on an out-of-band emission associated with each of the first beam and the second beam satisfying a threshold on out-of-band emission.

23. A method for wireless communication at a user equipment (UE), comprising: receiving a control message, the control message indicating: a first set of default operating frequencies for a first set of ports associated with a first transmission and reception point (TRP), and a second set of default operating frequencies for a second set of ports associated with a second TRP; and transmitting or receiving beam selection signaling based at least in part on the control message, wherein the beam selection signaling indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, the indication of the first beam being associated with a first mismatch between a first default operating frequency of the first port and a default operating frequency of the UE, and at least a second beam associated with a second port of the second set of ports, the indication of the second beam being associated with a second mismatch between a second default operating frequency of the second port and the default operating frequency of the UE.

24. The method of claim 23, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE being within a threshold mismatch and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE being within the threshold mismatch.

25. The method of claim 23, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving an indication of the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE.

26. The method of claim 23, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the beam selection signaling indicating a pair of receive beams of the UE for receiving a multi-TRP transmission from the first TRP and the second TRP.

27. The method of claim 23, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the beam selection signaling indicating a pair of transmit beams of the UE for transmitting a multi-TRP transmission to the first TRP and the second TRP.

28. A method for wireless communication at a first transmission and reception point (TRP), comprising: transmitting, to a user equipment (UE), a control message, the control message indicating: a first set of default operating frequencies for a first set of ports associated with the first TRP, and a second set of default operating frequencies for a second set of ports associated with a second TRP; and transmitting or receiving beam selection signaling based at least in part on the control message, wherein the beam selection signaling indicates: a selection of the first TRP and the second TRP for communication with the UE, at least a first beam associated with a first port of the first set of ports, the indication of the first beam being associated with a first mismatch between a first default operating frequency of the first port and a default operating frequency of the UE, and at least a second beam associated with a second port of the second set of ports, the indication of the second beam being associated with a second mismatch between a second default operating frequency of the second port and the default operating frequency of the UE. at least a first beam associated with a first port of the first set of ports, the indication of the first beam being associated with a first mismatch between a first default operating frequency of the first port and a default operating frequency of the UE, and at least a second beam associated with a second port of the second set of ports, the indication of the second beam being associated with a second mismatch between a second default operating frequency of the second port and the default operating frequency of the UE.

29. The method of claim 28, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the indication of the first beam associated with the first port and the second beam associated with the second port based at least in part on the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE being within a threshold mismatch and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE being within the threshold mismatch.

30. The method of claim 28, wherein, transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the indication of the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE. transmitting or receiving the beam selection signaling further comprises: transmitting or receiving the indication of the first mismatch between the first default operating frequency of the first port and the default operating frequency of the UE and the second mismatch between the second default operating frequency of the second port and the default operating frequency of the UE.

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