Techniques for beam failure recovery in multipath communications

Abstract

Methods, systems, and devices for wireless communication are described. A user equipment (UE) may communicate with a network entity using one or more directional beams. The UE may detect a beam failure associated with at least one of the one or more directional beams, and the UE may calculate a duration between the detected beam failure and a subsequent random access occasion. The UE may send a beam failure recovery (BFR) message to the network entity or to a second UE indicating the detected beam failure based on whether the calculated duration satisfies a threshold duration. For example, when the calculated duration is greater than or equal to the threshold duration, the UE may send the BFR message to the second UE. Alternatively, when the calculated duration is less than the threshold duration, the UE may send the BFR message to the network entity.

Description

[0001] Cross-references

[0002] This patent application claims priority to U.S. patent application No. 17 / 940,905, entitled “TECHNIQUES FOR BEAM FAILURE RECOVERY IN MULTI-PATH COMMUNICATIONS,” filed by Zhou et al. on September 8, 2022, which is assigned to the assignee of this application and is expressly incorporated herein by reference. Technical Field

[0003] The following relates to wireless communications, including techniques for beam failure recovery in multipath communications. Background Art

[0004] Wireless communication systems are widely deployed to provide various types of communication content, such as voice, video, packet data, messaging, broadcasting, and the like. These systems may be able to support communication with multiple users by sharing available system resources (e.g., time, frequency, and power). Examples of such multiple access systems include fourth generation (4G) systems (such as long term evolution (LTE) systems, advanced LTE (LTE-A) systems, or LTE-A Pro systems) and fifth generation (5G) systems (which may be referred to as new radio (NR) systems). These systems may employ techniques such as code division multiple access (CDMA), time division multiple access (TDMA), frequency division multiple access (FDMA), orthogonal FDMA (OFDMA), or discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM). A wireless multiple access communication system may include one or more base stations, each of which supports wireless communication for communication devices, which may be referred to as user equipment (UE). In some wireless communication systems, a UE may perform beam failure recovery (BFR) techniques when communicating with a network entity. However, some BFR techniques may be inefficient or introduce delays in beam recovery. Summary of the invention

[0005] The described technology relates to improved methods, systems, devices and apparatuses for supporting technologies for beam failure recovery in multipath communications. For example, the described technology provides conditional use of an access link or a relay link (e.g., a side link) to send a BFR message. A UE may communicate with a network entity using one or more directional beams, and the UE may detect a beam failure associated with at least one directional beam. Based on the duration between the detected beam failure and a subsequent opportunity for sending a random access channel (RACH) message, the UE may send the BFR message to the network entity or to a relay UE. For example, if the duration is greater than or equal to a threshold duration, the UE may send the BFR message to the relay UE. In this example, the UE may start a timer based on sending the BFR message to the relay UE, receiving a feedback message from the second UE, or both. If the timer expires before the UE receives a response to the BFR message from the network entity, the UE may alternatively perform a RACH procedure with the network entity. In another example, if the duration is less than the threshold duration, the UE may perform the RACH procedure with the network entity. In this example, the UE may select a directional beam and send a RACH message including the BFR message to the network entity using the directional beam. The UE may start a timer based on sending the random access message to the network entity. If the timer expires before the UE receives a RACH response, the UE may send the BFR message to the relay UE.

[0006] A method for wireless communication at a first UE is described. The method may include: communicating with a network entity using one or more directional beams; calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams; and sending a beam failure recovery message to the network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0007] An apparatus for wireless communication at a first UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: communicate with a network entity using one or more directional beams; calculate a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams; and send a beam failure recovery message to the network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0008] Another apparatus for wireless communication at a first UE is described. The apparatus may include: a component for communicating with a network entity using one or more directional beams; a component for calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams; and a component for sending a beam failure recovery message to the network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0009] A non-transitory computer-readable medium storing code for wireless communication at a first UE is described. The code may include instructions executable by a processor to perform the following actions: communicate with a network entity using one or more directional beams; calculate a duration between the detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams; and send a beam failure recovery message to the network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0010] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the beam failure recovery message may include operations, features, components, or instructions for the following actions: sending the beam failure recovery message to the second UE via a side link communication link based on the calculated duration failing to satisfy the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the network entity.

[0011] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: starting a timer based on sending the beam failure recovery message to the second UE; and monitoring the first directional beam for one or more downlink messages from the network entity based on starting the timer.

[0012] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: sending a random access message to the network entity based on the timer expiring before the one or more downlink messages can be received via the first directional beam; and communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based on sending the random access message to the network entity.

[0013] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, the timer may be started when the beam failure recovery message is sent to the second UE.

[0014] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: receiving a feedback message from the second UE in response to the beam failure recovery message indicating that the beam failure recovery message was successfully received at the second UE, wherein the timer may be started when the feedback message is received from the second UE.

[0015] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: receiving a feedback message from the second UE in response to the beam failure recovery message indicating that the beam failure recovery message was successfully received at the network entity, wherein the timer may be started when the feedback message is received from the second UE.

[0016] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, sending the beam failure recovery message may include operations, features, components, or instructions for the following actions: selecting a directional beam from a set of one or more candidate directional beams; and sending a random access message to the network entity via the selected directional beam based on the duration satisfying the threshold duration, the random access message including the beam failure recovery message.

[0017] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: starting a timer when sending the random access message to the network entity; and monitoring a random access response from the network entity based on starting the timer based on one or more measurement resources.

[0018] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: sending an additional beam failure recovery message to the second UE via a sidelink communication link based on the timer expiring before the random access response can be received, wherein the beam failure recovery message includes a request for beam refinement associated with the directional beam; and communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based on sending the additional beam failure recovery message to the second UE.

[0019] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for receiving a control message from the network entity indicating a configuration of the threshold duration, the threshold duration being based on access link channel conditions, side link channel conditions, capabilities of the UE, or any combination thereof.

[0020] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: receiving a control message to activate a beam failure recovery procedure from the network entity via a sidelink communication link with the second UE, wherein sending the beam failure recovery message to the network entity or to the second UE based on whether the calculated duration satisfies the threshold duration may be based on receiving the control message.

[0021] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: sending a request message to the network entity via the side link communication link with the second UE, the request message including a request to execute the beam failure recovery procedure, wherein receiving the control message for activating the beam failure recovery procedure using the second UE may be based on sending the request message.

[0022] A method for wireless communication at a network entity is described. The method may include: communicating with a first UE using one or more directional beams; and receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0023] An apparatus for wireless communication at a network entity is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be executable by the processor to cause the apparatus to: communicate with a first UE using one or more directional beams; and receive a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0024] Another apparatus for wireless communication at a network entity is described. The apparatus may include: a component for communicating with a first UE using one or more directional beams; and a component for receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0025] A non-transitory computer-readable medium storing code for wireless communication at a network entity is described. The code may include instructions executable by a processor to perform the following actions: communicate with a first UE using one or more directional beams; and receive a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0026] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the beam failure recovery message may include operations, features, components, or instructions for the following actions: receiving the beam failure recovery message from the second UE based on the duration failing to satisfy the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the first UE, the method further comprising: sending a downlink message to the first UE via the first directional beam and in response to receiving the beam failure recovery message, the downlink message scheduling one or more uplink transmissions.

[0027] In some examples of the methods, apparatus, and non-transitory computer-readable media described herein, receiving the beam failure recovery message may include operations, features, components, or instructions for the following actions: receiving a random access message from the first UE via a directional beam from a set of candidate directional beams based on the duration satisfying the threshold duration, the random access message including the beam failure recovery message, the method further comprising: sending a random access response to the first UE based on the random access message; and communicating with the first UE using a directional beam different from the at least one directional beam associated with the detected beam failure.

[0028] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: receiving a request message from the first UE via a sidelink communication link with one or more other UEs, the request message indicating a request to perform a beam failure recovery procedure; and sending a control message to the first UE via the sidelink communication link with the one or more other UEs to activate the beam failure recovery procedure, wherein the beam failure recovery message may be received from the second UE based on sending the control message.

[0029] A method for wireless communication at a second UE is described. The method may include receiving a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity, and sending the beam failure recovery message to the network entity via an uplink communication link.

[0030] An apparatus for wireless communication at a second UE is described. The apparatus may include a processor, a memory coupled to the processor, and instructions stored in the memory. The instructions may be capable of receiving a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity, and being executed by the processor so that the apparatus: receives a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity, and sends the beam failure recovery message to the network entity via an uplink communication link.

[0031] Another apparatus for wireless communication at a second UE is described. The apparatus may include: means for receiving a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity, and means for sending the beam failure recovery message to the network entity via an uplink communication link.

[0032] A non-transitory computer-readable medium storing code for wireless communication at a second UE is described. The code may include instructions executable by a processor to: receive a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity, and send the beam failure recovery message to the network entity via an uplink communication link.

[0033] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for the following actions: sending a feedback message to the first UE in response to receiving the beam failure recovery message, the feedback message indicating that the beam failure recovery message was successfully received at the second UE.

[0034] Some examples of the methods, apparatus, and non-transitory computer-readable media described herein may also include operations, features, components, or instructions for: receiving a first feedback message from the network entity in response to the beam failure recovery message, the first feedback message indicating that the beam failure recovery message was successfully received at the network entity; and sending a second feedback message to the second UE in response to receiving the first feedback message, the second feedback message indicating that the beam failure recovery message was successfully received at the network entity. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 An example of a wireless communication system supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated.

[0036] Figure 2 An example of a wireless communication system supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated.

[0037] Figure 3A and Figure 3B An example of a wireless communication system supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated.

[0038] Figure 4 and Figure 5 A block diagram of a device supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown.

[0039] Figure 6 A block diagram of a communication manager supporting techniques for beam failure recovery in multipath communications is shown in accordance with one or more aspects of the present disclosure.

[0040] Figure 7 A diagram of a system including a device supporting techniques for beam failure recovery in multipath communications is shown in accordance with one or more aspects of the present disclosure.

[0041] Figure 8 and Fig. 9 A block diagram of a device supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown.

[0042] Fig.10 A block diagram of a communication manager supporting techniques for beam failure recovery in multipath communications is shown in accordance with one or more aspects of the present disclosure.

[0043] Fig.11A diagram of a system including a device supporting techniques for beam failure recovery in multipath communications is shown in accordance with one or more aspects of the present disclosure.

[0044] Figures 12 to 17 A flow chart illustrating a method of supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. DETAILED DESCRIPTION

[0045] In some wireless communication systems, a user equipment (UE) and a network entity may communicate using directional beams. In some examples, the UE may identify a beam failure of one or more of the directional beams during communication with the network entity, which may be caused by deteriorating channel conditions, UE mobility, or other factors. The UE may perform a beam failure recovery (BFR) procedure to acquire a different directional beam and resume communication with the network entity. For example, as part of a random access channel (RACH) procedure, the UE may send a BFR message to the network entity via uplink communication.

[0046] However, some BFR procedures may be inefficient or may cause delays in notifying the network entity of beam failure. As an example, the network entity may not receive a RACH message from the UE, or the UE may not receive a RACH response to the RACH message from the network entity. Additionally, in order to transmit the RACH message, the UE may need to wait for an opportunity to send a RACH message to start the BFR procedure, which may result in increased latency and reduced communication efficiency.

[0047] The techniques, systems, and devices described herein enable a UE to perform conditional utilization of an access link or a relay link (e.g., a side link) with another device for sending a BFR message. For example, a UE may detect a beam failure associated with a directional beam used to communicate with a network entity. Based on the duration between the detected beam failure and the next available random access opportunity, the UE may send a BFR message to the network entity or to a relay UE. For example, if the duration is greater than or equal to a threshold duration, the UE may send a BFR message to a second relay UE. In this example, the UE may start a timer based on sending a BFR message to a second UE, receiving a feedback message from a second UE, or both. If the timer expires before the UE (e.g., from a network entity) receives a response to the BFR message, the UE may directly perform a RACH procedure with the network entity. In another example, if the duration is less than a threshold duration, the UE may perform a RACH procedure for BFR. In this example, the UE may select a directional beam and use the directional beam to send a random access message including the BFR message to the network entity. The UE may start a timer based on sending the random access message to the network entity. If the timer expires before the UE receives a random access response, the UE may send the BFR message to the relay UE.

[0048] Aspects of the present disclosure are first described in the context of wireless communication systems. Aspects of the present disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flow diagrams related to techniques for beam failure recovery in multipath communications.

[0049] Figure 1 An example of a wireless communication system 100 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated. The wireless communication system 100 may include one or more network entities 105, one or more UEs 115, and a core network 130. In some examples, the wireless communication system 100 may be a Long Term Evolution (LTE) network, an Advanced LTE (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating according to other systems and radio technologies, including future systems and radio technologies not explicitly mentioned herein.

[0050] The network entities 105 may be dispersed throughout a geographic area to form the wireless communication system 100, and may include devices in different forms or with different capabilities. In various examples, the network entities 105 may be referred to as network elements, mobility elements, radio access network (RAN) nodes, or network equipment, among other nomenclature. In some examples, the network entities 105 and the UE 115 may communicate wirelessly via one or more communication links 125 (e.g., radio frequency (RF) access links). For example, the network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) within which the UE 115 and the network entity 105 may establish one or more communication links 125. The coverage area 110 may be an example of a geographic area within which the network entity 105 and the UE 115 may support signal communications according to one or more radio access technologies (RATs).

[0051] The UEs 115 may be dispersed throughout the coverage area 110 of the wireless communication system 100, and each UE 115 may be stationary or mobile or both stationary and mobile at different times. The UEs 115 may be devices in different forms or with different capabilities. Figure 1 Some example UEs 115 are illustrated in FIG. 1. The UEs 115 described herein may be capable of supporting communications with various types of devices, such as Figure 1 Other UEs 115 or network entities 105 are shown.

[0052] As described herein, a node of the wireless communication system 100 (which may be referred to as a network node or a wireless node) may be a network entity 105 (e.g., any network entity described herein), a UE 115 (e.g., any UE described herein), a network controller, an apparatus, a device, a computing system, one or more components, or another suitable processing entity configured to perform any of the techniques described herein. For example, the node may be a UE 115. As another example, the node may be a network entity 105. As another example, a first node may be configured to communicate with a second node or a third node. In one aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a UE 115. In another aspect of this example, the first node may be a UE 115, the second node may be a network entity 105, and the third node may be a network entity 105. In other aspects of this example, the first node, the second node, and the third node may be different relative to these examples. Similarly, references to UE 115, network entity 105, apparatus, device, computing system, etc. may include disclosure of UE 115, network entity 105, apparatus, device, computing system, etc. as nodes. For example, a disclosure that UE 115 is configured to receive information from network entity 105 also discloses that the first node is configured to receive information from a second node.

[0053] In some examples, the network entities 105 may communicate with the core network 130 or with each other or both. For example, the network entities 105 may communicate with the core network 130 via one or more backhaul communication links 120 (e.g., according to S1, N2, N3, or other interface protocols). In some examples, the network entities 105 may communicate with each other via the backhaul communication links 120 (e.g., according to X2, Xn, or other interface protocols) directly (e.g., directly between the network entities 105) or indirectly (e.g., via the core network 130). In some examples, the network entities 105 may communicate with each other via the midhaul communication links 162 (e.g., according to the midhaul interface protocol) or the fronthaul communication links 168 (e.g., according to the fronthaul interface protocol) or any combination thereof. The backhaul communication links 120, the midhaul communication links 162, or the fronthaul communication links 168 may be or include one or more wired links (e.g., electrical links, optical fiber links), one or more wireless links (e.g., radio links, wireless optical links), etc. or various combinations thereof. UE 115 may communicate with core network 130 via communication link 155 .

[0054] One or more of the network entities 105 described herein may include or may be referred to as a base station 140 (e.g., a transceiver base station, a radio base station, an NR base station, an access point, a radio transceiver, a Node B, an evolved Node B (eNB), a next-generation Node B, or a gigabit Node B (any of which may be referred to as a gNB), a 5G NB, a next-generation eNB (ng-eNB), a home Node B, a home evolved Node B, or other suitable terminology). In some examples, the network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, stand-alone) base station architecture, which may be configured to utilize a protocol stack that is physically or logically integrated within a single network entity 105 (e.g., a single RAN node, such as a base station 140).

[0055] In some examples, the network entity 105 may be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) that may be configured to utilize a protocol stack that is physically or logically distributed between two or more network entities 105, such as an integrated access backhaul (IAB) network, an open RAN (O-RAN) (e.g., a network configuration sponsored by the O-RAN Alliance), or a virtualized RAN (vRAN) (e.g., a cloud RAN (C-RAN)). For example, the network entity 105 may include one or more of the following: a central unit (CU) 160, a distributed unit (DU) 165, a radio unit (RU) 170, a RAN intelligent controller (RIC) 175 (e.g., a near real-time RIC (near RT RIC), a non-real-time RIC (non-RT RIC)), a service management and orchestration (SMO) 180 system, or any combination thereof. The RU 170 may also be referred to as a radio head, a smart radio head, a remote radio head (RRH), a remote radio unit (RRU), or a transmit receive point (TRP). One or more components of the network entity 105 in the decomposed RAN architecture may be co-located, or one or more components of the network entity 105 may be located in distributed locations (e.g., separate physical locations). In some examples, one or more network entities 105 of the decomposed RAN architecture may be implemented as virtual units (e.g., virtual CU (VCU), virtual DU (VDU), virtual RU (VRU)).

[0056] The functional split between CU 160, DU 165, and RU 170 is flexible and can support different functions, depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, and any combination thereof) are performed at CU 160, DU 165, or RU 170. For example, a functional split of a protocol stack can be employed between CU 160 and DU 165, such that CU 160 can support one or more layers of a protocol stack and DU 165 can support one or more different layers of a protocol stack. In some examples, CU 160 can host higher protocol layer (e.g., layer 3 (L3), layer 2 (L2)) functions and signaling (e.g., radio resource control (RRC), service data adaptation protocol (SDAP), packet data convergence protocol (PDCP)). The CU 160 may be connected to one or more DUs 165 or RUs 170, and the one or more DUs 165 or RUs 170 may host lower protocol layers, such as layer 1 (L1) (e.g., physical (PHY) layer) or L2 (e.g., radio link control (RLC) layer, medium access control (MAC) layer) functions and signaling, and may each be at least partially controlled by the CU 160. Additionally or alternatively, a functional split of the protocol stack may be employed between the DU 165 and the RU 170, such that the DU 165 may support one or more layers of the protocol stack, and the RU 170 may support one or more different layers of the protocol stack. The DU 165 may support one or more different cells (e.g., via one or more RUs 170). In some cases, the functional split between CU 160 and DU 165 or between DU 165 and RU 170 may be within a protocol layer (e.g., some functions of a protocol layer may be performed by one of CU 160, DU 165, or RU 170, while other functions of the protocol layer are performed by a different one of CU 160, DU 165, or RU 170). CU 160 may be further functionally split into CU control plane (CU-CP) and CU user plane (CU-UP) functions. CU 160 may be connected to one or more DUs 165 via midhaul communication links 162 (e.g., F1, F1-c, F1-u), and DU 165 may be connected to one or more RUs 170 via fronthaul communication links 168 (e.g., an open fronthaul (FH) interface). In some examples, midhaul communication link 162 or fronthaul communication link 168 may be implemented based on an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities 105 that communicate via such communication links.

[0057] In a wireless communication system (e.g., wireless communication system 100), infrastructure and spectrum resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, thereby providing an IAB network architecture (e.g., to a core network 130). In some cases, in an IAB network, one or more network entities 105 (e.g., IAB nodes 104) may be partially controlled by each other. One or more IAB nodes 104 may be referred to as donor entities or IAB donors. One or more DUs 165 or one or more RUs 170 may be controlled in part by one or more CUs 160 associated with a donor network entity 105 (e.g., a donor base station 140). One or more donor network entities 105 (e.g., IAB donors) may communicate with one or more additional network entities 105 (e.g., IAB nodes 104) via supported access and backhaul links (e.g., backhaul communication links 120). The IAB node 104 may include an IAB mobile terminal (IAB-MT) controlled (e.g., scheduled) by a coupled IAB donor's DU 165. The IAB-MT may include an independent set of antennas for relaying communications with the UE 115, or may share the same antennas of the IAB node 104 (e.g., of the RU 170) for access via the DU 165 of the IAB node 104 (e.g., referred to as a virtual IAB-MT (vIAB-MT)). In some examples, the IAB node 104 may include a DU 165 that supports communication links with additional entities (e.g., IAB node 104, UE 115) within a relay chain or configuration (e.g., downstream) of the access network. In such cases, one or more components of the decomposed RAN architecture (e.g., one or more IAB nodes 104 or components of the IAB node 104) may be configured to operate according to the techniques described herein.

[0058] For example, an access network (AN) or RAN may include an access node (e.g., an IAB donor), communications between an IAB node 104, and one or more UEs 115. The IAB donor may facilitate a connection between the core network 130 and the AN (e.g., via a wired or wireless connection to the core network 130). That is, the IAB donor may refer to a RAN node having a wired or wireless connection to the core network 130. The IAB donor may include a CU 160 and at least one DU 165 (e.g., and RU 170), wherein the CU 160 may communicate with the core network 130 via an interface (e.g., a backhaul link). The IAB donor and the IAB node 104 may communicate via an F1 interface according to a protocol defining a signaling message (e.g., an F1 AP protocol). Additionally or alternatively, CU 160 may communicate with the core network via an interface (which may be an example of a portion of a backhaul link) and may communicate with other CUs 160 (e.g., CU 160 associated with an alternative IAB donor) via an Xn-C interface (which may be an example of a portion of a backhaul link).

[0059] An IAB node 104 may refer to a RAN node that provides IAB functionality (e.g., access for UE 115, wireless self-backhaul capabilities, etc.). The DU 165 may act as a distributed scheduling node toward child nodes associated with the IAB node 104, and the IAB-MT may act as a scheduled node toward a parent node associated with the IAB node 104. That is, an IAB donor may be referred to as a parent node that communicates with one or more child nodes (e.g., the IAB donor may relay for transmissions to UEs through one or more other IAB nodes 104). Additionally or alternatively, depending on the relay chain or configuration of the AN, the IAB node 104 may also be referred to as a parent node or child node of other IAB nodes 104. Thus, the IAB-MT entity of the IAB node 104 may provide a Uu interface for the child IAB node 104 to receive signaling from the parent IAB node 104 , and a DU interface (eg, DU 165 ) may provide a Uu interface for the parent IAB node 104 to signal to the child IAB node 104 or the UE 115 .

[0060] For example, the IAB node 104 may be referred to as a parent node supporting communications for a child IAB node or as a child IAB node associated with an IAB donor, or both. The IAB donor may include a CU 160 having a wired or wireless connection (e.g., backhaul communication link 120) to the core network 130, and may act as a parent node of the IAB node 104. For example, the DU 165 of the IAB donor may relay the transmission to the UE 115 through the IAB node 104, or may directly signal the transmission to the UE 115, or both. The CU 160 of the IAB donor may signal the establishment of a communication link to the IAB node 104 via the F1 interface, and the IAB node 104 may schedule the transmission (e.g., the transmission relayed from the IAB donor to the UE 115) via the DU 165. That is, data may be relayed to and from the IAB node 104 via signaling via the NR Uu interface of the MT to the IAB node 104. Communications with the IAB node 104 may be scheduled by the DU 165 of the IAB donor, and communications with the IAB node 104 may be scheduled by the DU 165 of the IAB node 104 .

[0061] In the case where the techniques described herein are applied to the context of a decomposed RAN architecture, one or more components of the decomposed RAN architecture may be configured to support the techniques for beam failure recovery in multipath communications as described herein. For example, some operations described as being performed by a UE 115 or a network entity 105 (e.g., a base station 140) may additionally or alternatively be performed by one or more components of the decomposed RAN architecture (e.g., an IAB node 104, a DU 165, a CU 160, a RU 170, a RIC 175, a SMO 180).

[0062] UE 115 may include or may be referred to as a mobile device, a wireless device, a remote device, a handheld device, or a subscriber device, or some other suitable term, where a "device" may also be referred to as a unit, a station, a terminal, or a client, etc. UE 115 may also include or may 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, UE 115 may include or may 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 communication (MTC) device, etc., which may be implemented in various objects such as appliances or vehicles, meters, etc.

[0063] The UE 115 described herein may be capable of communicating with various types of devices such as other UEs 115 which may sometimes act as relays, as well as network entities 105 and network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, etc. Figure 1 shown.

[0064] The UE 115 and the network entity 105 may wirelessly communicate with each other via one or more communication links 125 (e.g., access links) using resources associated with one or more carriers. The term "carrier" may refer to a collection of RF spectrum resources having a physical layer structure defined for supporting the communication link 125. For example, a carrier for the communication link 125 may include a portion of an RF spectrum band (e.g., a bandwidth portion (BWP)) that operates according to one or more physical layer channels for a given radio access technology (e.g., LTE, LTE-A, LTE-A Pro, NR). Each physical layer channel may carry acquisition signaling (e.g., synchronization signals, system information), control signaling for coordinating carrier operations, user data, or other signaling. The wireless communication system 100 may support communications with the UE 115 using carrier aggregation or multi-carrier operation. Depending on the carrier aggregation configuration, the UE 115 may be configured to have multiple downlink component carriers and one or more uplink component carriers. Carrier aggregation may be used for both frequency division duplex (FDD) and time division duplex (TDD) component carriers. Communication between the network entity 105 and other devices may refer to communication between these devices and any portion (e.g., entity, sub-entity) of the network entity 105. For example, the terms "send," "receive," or "communicate" when referring to the network entity 105 may refer to any portion of a network entity 105 (e.g., base station 140, CU 160, DU 165, RU 170) of a RAN communicating with another device (e.g., directly or via one or more other network entities 105).

[0065] In some examples, such as in a carrier aggregation configuration, a carrier may also have acquisition signaling or control signaling that coordinates the operation of other carriers. A carrier may be associated with a frequency channel (e.g., an Evolved Universal Mobile Telecommunications System Terrestrial Radio Access (E-UTRA) Absolute RF Channel Number (EARFCN)) and may be identified according to a channel raster for discovery by UE 115. A carrier may operate in a standalone mode, in which case initial acquisition and connection may be performed by UE 115 via the carrier, or a carrier may operate in a non-standalone mode, in which case the connection is anchored using a different carrier (e.g., a different carrier of the same or different radio access technology).

[0066] The communication link 125 shown in the wireless communication system 100 may include downlink transmissions (e.g., forward link transmissions) from the network entity 105 to the UE 115, uplink transmissions (e.g., return link transmissions) from the UE 115 to the network entity 105, or both, among other transmission configurations. A carrier may carry either downlink communications or uplink communications (e.g., in an FDD mode), or may be configured to carry both downlink communications and uplink communications (e.g., in a TDD mode).

[0067] A carrier may be associated with a particular bandwidth of the RF spectrum, and in some examples, the carrier bandwidth may be referred to as a "system bandwidth" of the carrier or wireless communication system 100. For example, the carrier bandwidth may be one of a set of bandwidths (e.g., 1.4 megahertz (MHz), 3 MHz, 5 MHz, 10 MHz, 15 MHz, 20 MHz, 40 MHz, or 80 MHz) of a carrier of a particular radio access technology. A device (e.g., a network entity 105, a UE 115, or both) of the wireless communication system 100 may have a hardware configuration that supports communications using a particular carrier bandwidth or may be capable of being configured to support communications using one of a set of carrier bandwidths. In some examples, the wireless communication system 100 may include a network entity 105 or a UE 115 that supports concurrent communications using carriers associated with multiple carrier bandwidths. In some examples, each served UE 115 may be configured to operate using a portion (e.g., a sub-band, a BWP) or all of a carrier bandwidth.

[0068] The signal waveform transmitted via the carrier may include 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 a system using MCM technology, a resource element may refer to a symbol period (e.g., the duration of a modulation symbol) and a resource of a subcarrier, in which case the symbol period and the subcarrier spacing may be inversely related. The number of bits carried by each resource element may depend on the modulation scheme (e.g., the order of the modulation scheme, the coding rate of the modulation scheme, or both), so that a relatively high number of resource elements (e.g., in the transmission duration) and a relatively high order modulation scheme may correspond to a relatively high rate of communication. Wireless communication resources may refer to a combination of RF spectrum resources, time resources, and spatial resources (e.g., spatial layers or beams), and the use of multiple spatial resources may increase the data rate or data integrity used for communication with UE 115.

[0069] One or more parameter sets for a carrier may be supported, and the parameter sets may include subcarrier spacing (Δf) and cyclic prefixes. A carrier may be divided into one or more BWPs with the same or different parameter sets. In some examples, a UE 115 may be configured with multiple BWPs. In some examples, a single BWP for a carrier may be active at a given time, and communications of a UE 115 may be constrained to one or more active BWPs.

[0070] The time interval for the network entity 105 or the UE 115 may be expressed as a multiple of a basic time unit, which may be, for example, a sampling period T s =1 / (Δf max ·N f ) seconds, for which Δf max It can represent the supported subcarrier spacing, and N f The supported discrete Fourier transform (DFT) size may be indicated. The time intervals of the communication resources may be organized according to radio frames each having a specified duration (e.g., 10 milliseconds (ms)). Each radio frame may be identified by a system frame number (SFN) (e.g., ranging from 0 to 1023).

[0071] Each frame may include multiple consecutively numbered subframes or time slots, and each subframe or time slot may have the same duration. In some examples, the frame may be divided into subframes (e.g., in the time domain), and each subframe may be further divided into a certain number of time slots. Alternatively, each frame may include a variable number of time slots, and the number of time slots may depend on the subcarrier spacing. Each time slot may include a certain number of symbol periods (e.g., depending on the length of the cyclic prefix appended in front of each symbol period). In some wireless communication systems 100, the time slot may be further divided into a plurality of micro time slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., N f The duration of a symbol period may depend on the subcarrier spacing or the operating frequency band.

[0072] A subframe, slot, mini-slot, or symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communication system 100 and may 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) may be variable. Additionally or alternatively, the smallest scheduling unit of the wireless communication system 100 may be dynamically selected (e.g., in a burst of a shortened TTI (sTTI)).

[0073] According to various techniques, physical channels may be multiplexed using carriers for communication. Physical control channels and physical data channels may be multiplexed for signaling via downlink carriers, for example, using one or more of a time division multiplexing (TDM) technique, a frequency division multiplexing (FDM) technique, or a hybrid TDM-FDM technique. A control region (e.g., a control resource set (CORESET)) of a physical control channel may be defined by a set of symbol periods and may extend across a system bandwidth of a carrier or a subset of that system bandwidth. One or more control regions (e.g., CORESETs) may be configured for a set of UEs 115. For example, one or more UEs in UE 115 may monitor or search a control region to obtain control information according to one or more search space sets, and each search space set may include one or more control channel candidates in one or more aggregation levels arranged in a cascaded manner. The aggregation level of a control channel candidate may refer to the amount of control channel resources (e.g., control channel elements (CCEs)) associated with coded information for a control information format having a given payload size. The search space sets may include a common search space set configured for transmitting control information to multiple UEs 115 , and a UE-specific search space set for transmitting control information to a specific UE 115 .

[0074] The network entity 105 may provide communication coverage via one or more cells (e.g., macro cells, small cells, hot spots, or other types of cells, or any combination thereof). The term "cell" may refer to a logical communication entity used to communicate with the network entity 105 (e.g., using a carrier), and may be associated with an identifier (e.g., a physical cell identifier (PCID), a virtual cell identifier (VCID), or other cell identifier) ​​used to distinguish adjacent cells. In some examples, a cell may also refer to a coverage area 110 or a portion of a coverage area 110 (e.g., a sector) on which a logical communication entity operates. Depending on various factors such as the capabilities of the network entity 105, such cells may range from smaller areas (e.g., structures, subsets of structures) to larger areas. For example, a cell may be or may include a building, a subset of a building, or an external space between or overlapping coverage areas 110, and the like.

[0075] A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access to a UE 115 that has a service subscription with a network provider that supports the macro cell. A small cell may be associated with a lower power network entity 105 (e.g., a lower power base station 140) than a macro cell, and the small cell may operate using the same or different (e.g., licensed, unlicensed) frequency band as the macro cell. A small cell may provide unrestricted access to a UE 115 that has a service subscription with a network provider, or may provide restricted access to a UE 115 associated with a small cell (e.g., a UE 115 in a closed subscriber group (CSG), a UE 115 associated with a user in a home or office). A network entity 105 may support one or more cells, and may also use one or more component carriers to support communications via one or more cells.

[0076] In some examples, a carrier may support multiple cells, and different cells may be configured according to different protocol types (e.g., MTC, narrowband IoT (NB-IoT), enhanced mobile broadband (eMBB)) that may provide access to different types of devices.

[0077] In some examples, the network entities 105 (e.g., base stations 140, RUs 170) may be mobile and thus provide communication coverage for mobile coverage areas 110. In some examples, different coverage areas 110 associated with different technologies may overlap, but the different coverage areas 110 may be supported by the same network entity 105. In some other examples, overlapping coverage areas 110 associated with different technologies may be supported by different network entities 105. The wireless communication system 100 may include, for example, a heterogeneous network in which different types of network entities 105 provide coverage for various coverage areas 110 using the same or different radio access technologies.

[0078] The wireless communication system 100 may support synchronous or asynchronous operation. For synchronous operation, the network entities 105 (e.g., base stations 140) may have similar frame timing, and transmissions from different network entities 105 may be approximately aligned in time. For asynchronous operation, the network entities 105 may have different frame timing, and in some examples, transmissions from different network entities 105 may not be aligned in time. The techniques described herein may be used for either synchronous operation or asynchronous operation.

[0079] Some UEs 115, such as MTC or IoT devices, may be low-cost or low-complexity devices and may provide automated communication between machines (e.g., via machine-to-machine (M2M) communication). M2M communication or MTC may refer to data communication technology that allows devices to communicate with each other or with a network entity 105 (e.g., base station 140) without human intervention. In some examples, M2M communication or MTC may include communication from devices that integrate sensors or meters to measure or acquire information and relay such information to a central server or application that uses the information or presents the information to a person interacting with the application. Some UEs 115 may be designed to collect information or implement automated behavior of machines or other devices. Examples of applications for MTC devices include: smart metering, inventory monitoring, water level monitoring, equipment monitoring, health care monitoring, wildlife monitoring, weather and geographic event monitoring, queue management and tracking, remote security sensing, physical access control, and transaction-based commercial charging.

[0080] Some UEs 115 may be configured to employ an operating mode that reduces power consumption, such as half-duplex communication (e.g., a mode that supports unidirectional communication via transmission or reception but does not transmit and receive concurrently). In some examples, half-duplex communication may be performed at a reduced peak rate. Other energy-saving techniques for UE 115 include entering a power-saving deep sleep mode when not engaged in active communications, operating using limited bandwidth (e.g., according to narrowband communications), or a combination of these techniques. For example, some UEs 115 may be configured to operate using a narrowband protocol type that is associated with a defined portion or range (e.g., a set of subcarriers or resource blocks (RBs)) within a carrier, within a guard band of a carrier, or outside a carrier.

[0081] The wireless communication system 100 may be configured to support ultra-reliable communication or low-latency communication or various combinations thereof. For example, the wireless communication system 100 may be configured to support ultra-reliable low-latency communication (URLLC). UE 115 may be designed to support ultra-reliable or low-latency or critical functions. Ultra-reliable communication may include private communication or group communication, and may be supported by one or more services (such as push-to-talk, video, or data). Support for ultra-reliable, low-latency functions may include prioritization of services, and such services may be used for public safety or general commercial applications. The terms ultra-reliable, low-latency, and ultra-reliable low-latency may be used interchangeably herein.

[0082] In some examples, the UE 115 may be configured to support communication directly with other UEs 115 via a device-to-device (D2D) communication link 135 (e.g., according to a peer-to-peer (P2P), D2D, or sidelink protocol). In some examples, one or more UEs 115 in a group that are performing D2D communication may be within a coverage area 110 of a network entity 105 (e.g., a base station 140, a RU 170), which may support aspects of such D2D communication configured (e.g., scheduled) by the network entity 105. In some examples, one or more UEs 115 in such a group may be outside the coverage area 110 of the network entity 105, or may otherwise be unable or not configured to receive transmissions from the network entity 105. In some examples, a group of UEs 115 communicating via D2D communication may support a one-to-many (1:M) system, in which each UE 115 transmits to each of the other UEs 115 in the group. In some examples, the network entity 105 may facilitate scheduling of resources for D2D communication. In some other examples, D2D communications may be performed between UEs 115 without involving network entity 105 .

[0083] In some systems, the D2D communication link 135 can be an example of a communication channel (such as a sidelink communication channel) between vehicles (e.g., UE 115). In some examples, the vehicles can communicate using vehicle-to-everything (V2X) communication, vehicle-to-vehicle (V2V) communication, or some combination of these items. The vehicles can signal information related to traffic conditions, signal scheduling, weather, safety, emergency situations, or any other information related to the V2X system. In some examples, the vehicles in the V2X system can communicate with roadside infrastructure (such as roadside units), or communicate with the network via one or more network nodes (e.g., network entity 105, base station 140, RU 170) using vehicle-to-network (V2N) communication, or both.

[0084] The core network 130 may provide user authentication, access authorization, tracking, Internet Protocol (IP) connectivity, and other access, routing or mobility functions. The core network 130 may be an evolved packet core (EPC) or a 5G core (5GC), which may include at least one control plane entity (e.g., a mobility management entity (MME), an access and mobility management function (AMF)) for managing access and mobility and at least one user plane entity (e.g., a serving gateway (S-GW), a packet data network (PDN) gateway (P-GW), or a user plane function (UPF)) for routing packets or interconnecting to an external network. The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management of UE 115 served by a network entity 105 (e.g., a base station 140) associated with the core network 130. User IP packets may be delivered through the user plane entity, which may provide IP address allocation and other functions. The user plane entity may be connected to the IP service 150 of one or more network operators. IP services 150 may include access to the Internet, an intranet, an IP Multimedia Subsystem (IMS), or packet-switched streaming services.

[0085] The wireless communication system 100 may operate using one or more frequency bands that may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz). Generally speaking, the region from 300 MHz to 3 GHz is referred to as the ultra-high frequency (UHF) region or decimeter band because the wavelength ranges from about one decimeter to one meter in length. UHF waves may be blocked or redirected by buildings and environmental features (which may be referred to as clusters), but these waves may be sufficient to penetrate structures so that macro cells provide services to UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than 100 kilometers) compared to communications using lower frequencies and longer waves in the high frequency (HF) or very high frequency (VHF) portions of the spectrum below 300 MHz.

[0086] The wireless communication system 100 may also operate using a super high frequency (SHF) region (also known as a centimeter band) that may be in the range of 3 GHz to 30 GHz or an extremely high frequency (EHF) region (e.g., 30 GHz to 300 GHz) (also known as a millimeter band) using a spectrum. In some examples, the wireless communication system 100 may support millimeter wave (mmW) communications between UE 115 and network entity 105 (e.g., base station 140, RU 170), and the EHF antenna of the corresponding device may be smaller and closer than the UHF antenna. In some examples, such technology may facilitate the use of antenna arrays within the device. However, the propagation of EHF transmissions may be affected by greater attenuation and shorter range than SHF or UHF transmissions. The technology disclosed herein may be adopted across transmissions using one or more different frequency regions, and the use of frequency bands specified across these frequency regions may vary by country or regulatory agency.

[0087] The wireless communication system 100 may utilize licensed and unlicensed RF spectrum bands. For example, the wireless communication system 100 may use unlicensed bands (such as the 5 GHz Industrial, Scientific, and Medical (ISM) band) to employ license assisted access (LAA), LTE unlicensed (LTE-U) radio access technology, or NR technology. When operating using unlicensed RF spectrum bands, devices such as network entity 105 and UE 115 may employ carrier sensing for conflict detection and avoidance. In some examples, operations using unlicensed bands may be based on carrier aggregation configuration (e.g., LAA) in conjunction with component carriers operating using licensed bands. Operations using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, and the like.

[0088] The network entity 105 (e.g., base station 140, RU 170) or UE 115 may be equipped with multiple antennas that can be used to employ technologies such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of the network entity 105 or UE 115 may be located in one or more antenna arrays or antenna panels, which may support MIMO operations or transmit or receive beamforming. For example, one or more base station antennas or antenna arrays may be co-located at an antenna assembly, such as an antenna tower. In some examples, antennas or antenna arrays associated with the network entity 105 may be located at different geographical locations. The network entity 105 may include an antenna array having a collection of multiple rows and columns of antenna ports that the network entity 105 may use to support beamforming for communications with the UE 115. Similarly, the UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally or alternatively, the antenna panel may support RF beamforming for signals sent via the antenna ports.

[0089] The network entity 105 or UE 115 may use MIMO communication to utilize multipath signal propagation and improve spectral efficiency by sending or receiving multiple signals via different spatial layers. Such technology may be referred to as spatial multiplexing. Multiple signals may be, for example, sent by a transmitting device via different antennas or different combinations of antennas. Similarly, multiple signals may be received by a receiving device via different antennas or different combinations of antennas. Each of the multiple signals may be referred to as a separate spatial stream and may carry information associated with the same data stream (e.g., the same codeword) or different data streams (e.g., different codewords). Different spatial layers may be associated with different antenna ports for channel measurement and reporting. MIMO technologies include single-user MIMO (SU-MIMO), in which multiple spatial layers are sent to the same receiving device; and multi-user MIMO (MU-MIMO), in which multiple spatial layers are sent to multiple devices.

[0090] Beamforming (which may also be referred to as spatial filtering, directional transmission, or directional reception) is a signal processing technique that may be used at a transmitting device or a receiving device (e.g., a network entity 105, a UE 115) to shape or direct an antenna beam (e.g., a transmit beam, a receive beam) along a spatial path between the transmitting device and the receiving device. Beamforming may be achieved by combining signals conveyed via antenna elements of an antenna array so that some signals propagating along a particular direction relative to the antenna array experience constructive interference, while other signals experience destructive interference. Adjustments to signals conveyed via antenna elements may include the transmitting device or the receiving device applying an amplitude offset, a phase offset, or both to signals carried via antenna elements associated with the device. Adjustments associated with each of these antenna elements may be defined by a set of beamforming weights associated with a particular direction (e.g., relative to the antenna array of the transmitting device or the receiving device or relative to some other direction).

[0091] The network entity 105 or UE 115 may use beam scanning techniques as part of a beamforming operation. For example, the network entity 105 (e.g., base station 140, RU 170) may use multiple antennas or antenna arrays (e.g., antenna panels) to perform beamforming operations for directional communication with UE 115. Some signals (e.g., synchronization signals, reference signals, beam selection signals, or other control signals) may be sent multiple times by the network entity 105 along different directions. For example, the network entity 105 may send signals according to different sets of beamforming weights associated with different transmission directions. Transmissions along different beam directions may be used to identify (e.g., by a transmitting device (such as network entity 105), or by a receiving device (such as UE 115)) beam directions for later transmission or reception by the network entity 105.

[0092] Some signals, such as data signals associated with a particular receiving device, may be sent by a sending device (e.g., a sending network entity 105, a sending UE 115) along a single beam direction (e.g., a direction associated with a receiving device (such as a receiving network entity 105 or a receiving UE 115)). In some examples, a beam direction associated with transmission along a single beam direction may be determined based on signals sent along one or more beam directions. For example, UE 115 may receive one or more of the signals sent by network entity 105 along different directions, and may report to network entity 105 an indication of the signal received by UE 115 with the highest signal quality or other acceptable signal quality.

[0093] In some examples, transmission by a device (e.g., by network entity 105 or UE 115) may be performed using multiple beam directions, and the device may use a combination of digital precoding or beamforming to generate a combined beam for transmission (e.g., from network entity 105 to UE 115). UE 115 may report feedback indicating precoding weights for one or more beam directions, and the feedback may correspond to a configured set of beams across a system bandwidth or one or more subbands. Network entity 105 may send a reference signal (e.g., a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS)), which may be precoded or non-precoded. UE 115 may provide feedback for beam selection, which may be a precoding matrix indicator (PMI) or codebook-based feedback (e.g., a multi-panel codebook, a linear combination codebook, a port selection codebook). Although these techniques are described with reference to signals sent along one or more directions by a network entity 105 (e.g., base station 140, RU 170), UE 115 may use similar techniques to send signals multiple times along different directions (e.g., to identify a beam direction for subsequent transmission or reception by UE 115), or to send signals along a single direction (e.g., to send data to a receiving device).

[0094] A receiving device (e.g., UE 115) may perform receiving operations according to multiple receiving configurations (e.g., directional listening) when receiving various signals (such as synchronization signals, reference signals, beam selection signals, or other control signals) from a receiving device (e.g., network entity 105). For example, the receiving device may perform reception according to multiple receiving directions by receiving via different antenna subarrays, processing received signals according to different antenna subarrays, receiving according to different receiving beamforming weight sets (e.g., different directional listening weight sets) applied to signals received at multiple antenna elements of an antenna array, or processing received signals according to different receiving beamforming weight sets applied to signals received at multiple antenna elements of an antenna array, any of which may be referred to as "listening" according to different receiving configurations or receiving directions. In some examples, the receiving device may use a single receiving configuration to receive along a single beam direction (e.g., when receiving a data signal). A single receive configuration may be aligned along a beam direction determined based on listening according to different receive configuration directions (e.g., a beam direction determined to have the highest signal strength, highest signal-to-noise ratio (SNR), or other acceptable signal quality based on listening according to multiple beam directions).

[0095] The wireless communication system 100 may be a packet-based network that operates according to a layered protocol stack. In the user plane, communications at the bearer or PDCP layer may be IP-based. The RLC layer may perform packet segmentation and reassembly to communicate via logical channels. The MAC layer may perform priority processing and multiplexing of logical channels into transport channels. The MAC layer may also implement error detection techniques, error correction techniques, or both to support retransmission to improve link efficiency. In the control plane, the RRC layer may provide the establishment, configuration, and maintenance of an RRC connection that supports a radio bearer for user plane data between the UE 115 and the network entity 105 or the core network 130. The PHY layer may map a transport channel to a physical channel.

[0096] UE 115 and network entity 105 may support retransmission of data to increase the likelihood that the data is successfully received. Hybrid automatic repeat request (HARQ) feedback is a technique for increasing the likelihood of correctly receiving data via a communication link (e.g., communication link 125, D2D communication link 135). HARQ may 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 may improve throughput at the MAC layer under poor radio conditions (e.g., low signal-to-noise ratio conditions). In some examples, a device may support same-slot HARQ feedback, in which case the device may provide HARQ feedback in a specific time slot for data received in a previous symbol in the time slot. In some other examples, the device may provide HARQ feedback in a subsequent time slot or according to some other time interval.

[0097] The wireless communication system 100 may support communication between the UE 115 and the network entity 105 to perform a BFR procedure. For example, the UE 115 may send a signaling to the network entity 105 to resume communication using a directional beam by performing a RACH procedure to establish a wireless connection between the UE 115 and the network entity 105. The UE 115 may be connected to the network entity 105 via a direct Uu interface link (e.g., a Uu link). The UE 115 may communicate control information and data to the network entity 105 via the Uu link. The UE 115 may be configured to monitor a plurality of candidate directional beams for beam condition maintenance and BFR procedures. The UE 115 may send a BFR message to the network entity 105 to resume communication using another beam, wherein the BFR message may include information about a preferred beam among the directional beams.

[0098] For example, UE 115 may send an initial RACH message (e.g., msg1 or msgA) to network entity 105 via an uplink communication link. The RACH message may include a BFR message. However, in some examples, network entity 105 may not receive a RACH message including a BFR message, or UE 115 may not receive a RACH response to the BFR message from network entity 105. Additionally, using RACH for a BFR procedure may be relatively inefficient because UE 115 may wait for an opportunity to send a RACH message to start a BFR procedure, which may result in increased latency and reduced communication efficiency.

[0099] The wireless communication system 100 may support an enhanced BFR procedure for conditional utilization of an access link or a relay link (e.g., a side link). The enhanced BFR procedure (e.g., an enhanced BFR with UE cooperation) may include using a side link (e.g., auxiliary) communication with one or more relay UEs 115 to improve communication reliability. The UE 115 may send a BFR message to the relay UE 115 based on the availability of the side link resources (e.g., the availability of the relay UE 115 on the side link). For example, the UE 115 may communicate with the network entity 105 using a directional beam, and the UE 115 may detect a beam failure associated with the beam. Based on the duration between the detected beam failure and the next available random access opportunity, the UE 115 may send a BFR message to the network entity 105 or to the relay UE 115. That is, the UE 115 may determine whether to send data communication to the network entity 105 or to the relay UE 115 based on the threshold duration.

[0100] For example, if the duration from detecting beam failure until the next random access opportunity is greater than or equal to (e.g., does not meet) a threshold duration, the UE 115 may send a BFR message to the relay UE 115 via a side link. Here, the UE 115 and the relay UE 115 may be connected via a PC5 interface, where a side link data transmission resource may be pre-configured and available for side link communication between the UEs 115. The relay UE 115 may be connected to the network entity via a Uu link. In this example, the UE 115 may start a timer based on sending a BFR message to the relay UE 115, receiving a feedback message from the relay UE 115, or both. If the timer expires before the UE 115 (e.g., from the network entity 105) receives a response to the BFR message, the UE 115 may directly perform a RACH procedure with the network entity 105.

[0101] In another example, if the duration from the detected beam failure until the next random access opportunity is less than (e.g., satisfies) a threshold duration, the UE 115 may perform a RACH procedure for BFR with the network entity 105. In this example, the UE 115 may select a directional beam and send a RACH message including a BFR message to the network entity 105 using the directional beam. The UE 115 may start a timer based on sending the RACH message to the network entity 105. If the timer expires before the UE 115 receives a RACH response (e.g., msg2 or msgB), the UE 115 may send a BFR message to the relay UE 115.

[0102] Figure 2An example of a wireless communication system 200 that supports techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated. The wireless communication system 200 may implement or may be implemented to implement or facilitate aspects of the wireless communication system 100. For example, the wireless communication system 200 illustrates communications between a UE 115-a, a relay UE 115-b, and a network entity 105-a. The UE 115-a, the relay UE 115-b, and the network entity 105-a may be reference Figure 1 Examples of corresponding devices are illustrated and described. In some implementations, the UE 115-a, relay UE 115-b, and network entity 105-a may support performing enhanced BFR procedures by communicating BFR messages to reestablish beam communications.

[0103] In some examples, UE 115-a may send RACH message 210 to network entity 105-a via uplink communication link 205-a to perform RACH procedure. In some aspects, the RACH message may include BFR information. In other examples, UE 115-a may send BFR message 220-a to relay UE 115-b via sidelink communication link 215. Relay UE 115-b may send (e.g., relay) BFR message 220-b to network entity 105-a via uplink communication link 205-b. As part of the enhanced BFR procedure, UE 115-a may determine which of these messages (e.g., RACH message 210 or BFR message 220) to send.

[0104] As an example, UE 115-a may determine whether to send a RACH message 210 to network entity 105-a or a BFR message 220 to UE 115-b based on elapsed time 240 and a threshold elapsed time. Elapsed time 240 may be the amount of time between a RACH opportunity 225 (e.g., RACH opportunity 225-c) and the time when UE 115-a detects a beam failure event (beam failure declaration 230). In such cases, UE 115-a may determine a beam failure and calculate (e.g., estimate) elapsed time 240 based on a set of configured RACH opportunities. For example, multiple RACH opportunities 225 (e.g., RACH opportunities 225-a, 225-b, and 225-c) may have some periodicity 235 for sending a RACH message 210. Periodicity 235 may be T milliseconds (e.g., 80 milliseconds). UE 115-a may determine elapsed time 240, which may be X (e.g., X milliseconds). UE 115-a may be configured by network entity 105-a with a threshold elapsed time (e.g., threshold A (e.g., A milliseconds)). In some examples, elapsed time 240 may be greater than or equal to the threshold elapsed time (X≥A), such that elapsed time 240 may fail to meet the threshold elapsed time. If elapsed time 240 fails to meet the threshold, UE 115-a may send a BFR message 220 to relay UE 115-b. BFR message 220 may be included in the transmission of a MAC control element (MAC-CE) on sidelink communication link 215. Relay UE 115-b may send BFR message 220 to network entity 105-a such that UE 115-a and network entity 105 may resume the BFR procedure. Alternatively, if elapsed time 240 meets the threshold elapsed time (X<A), UE 115-a may perform a RACH procedure with network entity 105-b by sending a RACH message 210.

[0105] UE 115-a may be configured with a threshold elapsed time by an RRC message from network entity 105-a. Network entity 105-a may select a value for the threshold elapsed time based on one or more of uplink channel conditions, sidelink channel conditions, or the capabilities of UE 115-a and other examples. For example, network entity 105-a may determine that the sidelink channel condition is relatively more efficient for communication than the uplink channel condition, and network entity 105-a may select a relatively small threshold elapsed time. For example, UE 115-a may be more likely to send a BFR message to relay UE 115-b based on a relatively small threshold elapsed time. In some aspects, network entity 105-a may configure multiple values for the threshold elapsed time for UE 115-a, and network entity 105-a may send a MAC-CE or downlink control information (DCI) to select different values of the threshold elapsed time (e.g., a handover configuration).

[0106] In some examples, the UE 115-a and the network entity 105-a may activate or deactivate the enhanced UE BFR procedure via downlink communication or uplink communication. For example, the UE 115-a may send uplink control information (UCI) or MAC-CE to the network entity 105-a to activate or deactivate the enhanced BFR procedure. In another example, the network entity 105-a may send DCI or MAC-CE to the UE 115-a to activate or deactivate the enhanced BFR procedure. The UE 115-a or the network entity 105-a may activate or deactivate the enhanced BFR procedure based on one or more of the following: sidelink resource availability, sidelink channel conditions of the sidelink communication link 215 between the UE 115-a and the relay UE 115-b, quality of service (QoS) requirements of the service business, power constraints, capacity constraints, capability constraints of the UE 115-a, and other examples. Thus, the enhanced BFR procedure may result in improved QoS, reduced wireless communication latency, and reduced power consumption.

[0107] Figure 3A An example of a wireless communication system 300-a that supports techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated. The wireless communication system 300-a may implement or be implemented to implement or facilitate aspects of the wireless communication system 100 and the wireless communication system 200. For example, the wireless communication system 300-a illustrates an example of an enhanced BFR procedure between a UE 115-c, a relay UE 115-d, and a network entity 105-b. The UE 115-c, the UE 115-d, and the network entity 105-b may be reference Figure 1 and Figure 2 Examples of corresponding devices are illustrated and described. In some implementations, the UE 115-c, the relay UE 115-d, and the network entity 105-b may support performing enhanced BFR procedures by communicating BFR messages to reestablish beam communications.

[0108] As described herein, UE 115-c may determine to send a BFR message to relay UE 115-d based on a duration between a detected beam failure and a subsequent RACH opportunity failing to satisfy (e.g., being greater than or equal to) a threshold duration. In some examples, UE 115-c may send a RACH message to network entity 105-b, for example, based on a failure to receive a response to the BFR message before a timer expires. In such cases, UE 115-c may fall back to signaling BFR information using a RACH message. Here, UE 115-c may start timer Y associated with receiving a response to the BFR message from network entity 105-b.

[0109] In one example, UE 115-c may start timer Y based on sending a BFR message to relay UE 115-d (e.g., timer Y may be started when the BFR message is sent to UE 115-d). Additionally or alternatively, UE 115-c may start timer Y based on receiving a feedback message 310-a from relay UE 115-d via sidelink communication link 315-a, where feedback message 310-a may indicate that UE 115-d received the BFR message (e.g., feedback message 310-b may include an acknowledgment (ACK) from relay UE 115-d). In other examples, UE 115-c may start timer Y based on receiving an indication 312 of feedback message 310-b from relay UE 115-d via sidelink communication link 315-a. For example, relay UE 115-d may send the relayed BFR message to network entity 105-b. In response, the network entity 105-b may send a feedback message 310-b (e.g., ACK) to the relay UE 115-d via the downlink communication link 305-a to confirm that the network entity 105-b received the relayed BFR message. The relay UE 115-d may send an indication 312 that the relay UE 115-d received the feedback message 310-b.

[0110] In some examples, network entity 105-b may send a physical downlink control channel (PDCCH) message to UE 115-c before timer Y expires. Network entity 105-b may send a PDCCH message that may carry DCI message 320 via a directional beam (e.g., a preferred beam) indicated by UE 115-a in a BFR message, and DCI message 310 may include information for scheduling new data transmissions from UE 115-c. In some aspects, new data transmissions may be scheduled based on the directional beam indicated by the BFR message. That is, UE 115-c may send data transmissions using a directional beam that is indicated by the BFR message and is different from the directional beam that experienced the detected beam failure. Therefore, UE 115-c and network entity 105-b may communicate using one or more additional directional beams based on the enhanced BFR procedures described herein.

[0111] Alternatively, timer Y may expire before UE 115-c receives the PDCCH message or DCI message 320 from network entity 105-b. In this example, UE 115-c may switch to performing a RACH procedure with network entity 105-b. In such a case, a RACH message may be sent to network entity 105-b, which may include a BFR message. In such a case, one or more additional beams may be selected to resume communication between UE 115-c and network entity 105-b.

[0112] The network entity 105-b may configure timer Y for the UE 115-c by sending an RRC message to the UE 115-c via the downlink communication link 305-b. The network entity 105-b may send the RRC message before receiving the BFR message from the relay UE 115-d (e.g., before the starting point of timer Y). The network entity may configure a different timer Y value based on an indication selected by the UE 115-c for the starting point of timer Y. In some examples, the network entity 105-b may send a MAC-CE or another DCI message 320 to switch the value of timer Y to another value.

[0113] Figure 3B An example of a wireless communication system 300-b that supports techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is illustrated. The wireless communication system 300-b may implement or be implemented to implement or facilitate aspects of the wireless communication system 100 and the wireless communication system 200. For example, the wireless communication system 300-b illustrates an example of an enhanced BFR procedure between a UE 115-e, a relay UE 115-f, and a network entity 105-c. The UE 115-e, the UE 115-f, and the network entity 105-c may be reference Figure 1 and Figure 2 Examples of corresponding devices are illustrated and described. In some implementations, the UE 115-e, relay UE 115-f, and network entity 105-c may support performing enhanced BFR procedures by communicating BFR messages to reestablish beam communications.

[0114] As described herein, upon detecting a beam failure associated with one or more directional beams, the UE 115-e may send a RACH message 330 to the network entity 105-c via the uplink communication link 345. For example, as part of a BFR procedure, the UE 115-e may initially perform a RACH procedure on the uplink communication link 345. The UE 115-e may select an SSB beam (e.g., a best SSB beam) from a pre-configured set of candidate beams, and the UE 115-e may send the RACH message 330 (e.g., msg1 or msgA) on the selected SSB beam. In some aspects, the UE 115-e may start a timer X after sending the RACH message 330, where the timer X is associated with receiving a random access response (RAR) from the network entity 105-c in response to the RACH message 330. In some examples, UE 115 - e may receive a RAR from network entity 105 - c before timer X expires, and UE 115 - e and network entity 105 - c may continue the RACH procedure by sending other signaling (e.g., msg3).

[0115] Alternatively, the UE 115-e may fail to receive the RAR from the network entity 105-c before the timer X expires. In this example, the UE 115-e may switch to sending a BFR message 325 to the relay UE 115-f via the sidelink communication link 315-b to complete the BFR procedure. That is, if no response is received before the timer X expires, the UE 115-e may accordingly send a BFR message 325 (e.g., a BFR MAC-CE) to the relay UE 115-f via the sidelink communication link. In some aspects, because the RACH procedure failed on the selected SSB beam, the UE 115-e may include in the BFR message 325 a request for the network entity 105-c to perform beam refinement. As an example, the request may instruct the network entity 105-c to perform beam refinement on the corresponding selected SSB beam (e.g., SSB beam 335) for the initial RACH procedure.

[0116] In some examples, the network entity 105-c may scan multiple CSI-RS beams associated with the SSB beam 335 (e.g., CSI-RS beam 340-a and CSI-RS beam 340-b). The network entity 105-c may select the best CSI-RS beam (e.g., CSI-RS beam 340-a). The network entity 105-c may send DCI to the UE 115-e via the selected CSI-RS beam 340-a, and the UE 115-e may perform a measurement procedure on the CSI-RS beam 340-a. The UE 115-e may perform the measurement procedure based on the pre-configured CSI-RS measurement resources.

[0117] The network entity 105-c may configure the timer X for the UE 115-e by sending an RRC message to the UE 115-e via a downlink communication link. In some examples, the network entity 105-b may send a MAC-CE or another DCI message 320 to switch the value of the timer X to another value.

[0118] Figure 4 A block diagram 400 of a device 405 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 405 may be an example of aspects of a UE 115 as described herein. The device 405 may include a receiver 410, a transmitter 415, and a communication manager 420. The device 405 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0119] Receiver 410 may provide means for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for beam failure recovery in multipath communications). The information may be passed to other components of device 405. Receiver 410 may utilize a single antenna or a collection of multiple antennas.

[0120] The transmitter 415 may provide means for transmitting signals generated by other components of the device 405. For example, the transmitter 415 may transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for beam failure recovery in multipath communications). In some examples, the transmitter 415 may be co-located with the receiver 410 in a transceiver module. The transmitter 415 may utilize a single antenna or a collection of multiple antennas.

[0121] The communication manager 420, the receiver 410, the transmitter 415, or various combinations thereof, or various components thereof, may be examples of means for performing various aspects of the techniques for beam failure recovery in multipath communications as described herein. For example, the communication manager 420, the receiver 410, the transmitter 415, or various combinations thereof, or components thereof, may support methods for performing one or more of the functions described herein.

[0122] In some examples, the communication manager 420, the receiver 410, the transmitter 415, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a digital signal processor (DSP), a central processing unit (CPU), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured to or otherwise supports components for performing the functions described in the present disclosure. In some examples, the processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by executing instructions stored in the memory by the processor).

[0123] Additionally or alternatively, in some examples, the communication manager 420, the receiver 410, the transmitter 415, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 420, the receiver 410, the transmitter 415, or various combinations or components thereof may be performed by a general purpose processor (e.g., configured as or otherwise supporting components for performing the functions described in the present disclosure), a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices.

[0124] In some examples, communication manager 420 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with receiver 410, transmitter 415, or both. For example, communication manager 420 may receive information from receiver 410, transmit information to transmitter 415, or be integrated in conjunction with receiver 410, transmitter 415, or both to obtain information, output information, or perform various other operations as described herein.

[0125] According to examples as disclosed herein, the communication manager 420 may support wireless communications at the first UE. For example, the communication manager 420 may be configured to or otherwise support components for communicating with a network entity using one or more directional beams. The communication manager 420 may be configured to or otherwise support components for calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The communication manager 420 may be configured to or otherwise support components for sending a beam failure recovery message to a network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0126] Additionally or alternatively, according to examples as disclosed herein, the communication manager 420 may support wireless communication at the second UE. For example, the communication manager 420 may be configured to or otherwise support components for receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The communication manager 420 may be configured to or otherwise support components for sending the beam failure recovery message to the network entity via an uplink communication link.

[0127] By including or configuring the communication manager 420 according to the examples described herein, the device 405 (e.g., a processor controlling the receiver 410, the transmitter 415, the communication manager 420, or a combination thereof or otherwise coupled thereto) can support techniques for reducing power consumption and more efficiently utilizing communication resources. For example, by performing BFR techniques using a sidelink communication link with another UE, the processor of the device 405 can more efficiently send BFR messages and communicate with network entities.

[0128] Figure 5 A block diagram 500 of a device 505 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 505 may be an example of aspects of the device 405 or UE 115 as described herein. The device 505 may include a receiver 510, a transmitter 515, and a communication manager 520. The device 505 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0129] The receiver 510 may provide means for receiving information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for beam failure recovery in multipath communications). The information may be passed to other components of the device 505. The receiver 510 may utilize a single antenna or a collection of multiple antennas.

[0130] The transmitter 515 may provide means for transmitting signals generated by other components of the device 505. For example, the transmitter 515 may transmit information (such as packets, user data, control information, or any combination thereof) associated with various information channels (e.g., control channels, data channels, information channels related to techniques for beam failure recovery in multipath communications). In some examples, the transmitter 515 may be co-located with the receiver 510 in a transceiver module. The transmitter 515 may utilize a single antenna or a collection of multiple antennas.

[0131] The device 505 or its various components may be examples of components for performing various aspects of the techniques for beam failure recovery in multipath communications as described herein. For example, the communication manager 520 may include a beam communication component 525, a beam failure calculation component 530, a beam failure recovery transmission component 535, a beam failure receiving component 540, a beam failure transmission component 545, or any combination thereof. The communication manager 520 may be an example of various aspects of the communication manager 420 as described herein. In some examples, the communication manager 520 or its various components may be configured to use or otherwise cooperate with the receiver 510, the transmitter 515, or both to perform various operations (e.g., receive, obtain, monitor, output, transmit). For example, the communication manager 520 may receive information from the receiver 510, transmit information to the transmitter 515, or be integrated with the receiver 510, the transmitter 515, or both to obtain information, output information, or perform various other operations as described herein.

[0132] According to examples as disclosed herein, the communication manager 520 may support wireless communications at the first UE. The beam communication component 525 may be configured to or otherwise support components for communicating with a network entity using one or more directional beams. The beam failure calculation component 530 may be configured to or otherwise support components for calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The beam failure recovery sending component 535 may be configured to or otherwise support components for sending a beam failure recovery message to a network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0133] Additionally or alternatively, according to examples as disclosed herein, the communication manager 520 may support wireless communication at the second UE. The beam failure receiving component 540 may be configured to or otherwise support components for receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The beam failure sending component 545 may be configured to or otherwise support components for sending the beam failure recovery message to the network entity via an uplink communication link.

[0134] Figure 6A block diagram 600 of a communication manager 620 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The communication manager 620 may be an example of aspects of the communication manager 420, the communication manager 520, or both as described herein. The communication manager 620 or its various components may be examples of components for performing various aspects of the techniques for beam failure recovery in multipath communications as described herein. For example, the communication manager 620 may include a beam communication component 625, a beam failure calculation component 630, a beam failure recovery transmission component 635, a beam failure reception component 640, a beam failure transmission component 645, a beam selection component 650, a random access transmission component 655, a control message reception component 660, a request message transmission component 665, a feedback message transmission component 670, a feedback message reception component 675, a timer component 680, a beam monitoring component 685, a feedback message component 690, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses).

[0135] According to examples as disclosed herein, the communication manager 620 may support wireless communications at the first UE. The beam communication component 625 may be configured to or otherwise support components for communicating with a network entity using one or more directional beams. The beam failure calculation component 630 may be configured to or otherwise support components for calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The beam failure recovery sending component 635 may be configured to or otherwise support components for sending a beam failure recovery message to a network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0136] In some examples, to support sending a beam failure recovery message, the beam failure recovery sending component 635 may be configured as or otherwise support a component for sending a beam failure recovery message to a second UE via a side link communication link based on a calculated duration failing to satisfy a threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the network entity.

[0137] In some examples, timer component 680 may be configured or otherwise support components for starting a timer based on sending a beam failure recovery message to a second UE. In some examples, beam monitoring component 685 may be configured or otherwise support components for monitoring a first directional beam for one or more downlink messages from a network entity based on starting a timer.

[0138] In some examples, the random access transmission component 655 may be configured or otherwise support components for transmitting a random access message to a network entity based on a timer expiring prior to receiving one or more downlink messages via a first directional beam. In some examples, the beam communication component 625 may be configured or otherwise support components for communicating with a network entity using a directional beam different from at least one directional beam associated with a detected beam failure based on transmitting a random access message to the network entity.

[0139] In some examples, the timer is started when a beam failure recovery message is sent to the second UE.

[0140] In some examples, the feedback message component 690 may be configured as or otherwise support a component for receiving a feedback message from a second UE in response to a beam failure recovery message indicating that the beam failure recovery message was successfully received at the second UE, wherein the timer is started when the feedback message is received from the second UE.

[0141] In some examples, a feedback message is received from a second UE in response to the beam failure recovery message indicating that the beam failure recovery message was successfully received at the network entity, wherein the timer is started when the feedback message is received from the second UE.

[0142] In some examples, to support sending a beam failure recovery message, the beam selection component 650 may be configured or otherwise support a component for selecting a directional beam from a set of one or more candidate directional beams. In some examples, to support sending a beam failure recovery message, the random access transmission component 655 may be configured or otherwise support a component for sending a random access message to a network entity via the selected directional beam based on the duration satisfying the threshold duration, the random access message including the beam failure recovery message.

[0143] In some examples, timer component 680 can be configured or otherwise support components for starting a timer when sending a random access message to a network entity. In some examples, beam monitoring component 685 can be configured or otherwise support components for monitoring a random access response from a network entity based on starting a timer based on one or more measurement resources.

[0144] In some examples, the beam failure recovery sending component 635 may be configured to or otherwise support components for sending an additional beam failure recovery message to the second UE via the sidelink communication link based on the timer expiring before receiving the random access response, wherein the beam failure recovery message includes a request for beam refinement associated with the directional beam. In some examples, the beam communication component 625 may be configured to or otherwise support components for communicating with a network entity using a directional beam different from at least one directional beam associated with the detected beam failure based on sending the additional beam failure recovery message to the second UE.

[0145] In some examples, the control message receiving component 660 may be configured as or otherwise support components for receiving a configured control message from a network entity indicating a threshold duration based on access link channel conditions, side link channel conditions, UE capabilities, or any combination thereof.

[0146] In some examples, the control message receiving component 660 may be configured as or otherwise support components for receiving a control message for activating a beam failure recovery procedure from a network entity via a sidelink communication link with a second UE, wherein sending the beam failure recovery message to the network entity or to the second UE is based on receiving the control message based on whether the calculated duration satisfies a threshold duration.

[0147] In some examples, the request message sending component 665 may be configured as or otherwise support components for sending a request message to a network entity via a sidelink communication link with a second UE, the request message including a request to perform a beam failure recovery procedure, wherein receiving a control message for activating the beam failure recovery procedure using the second UE is based on sending the request message.

[0148] Additionally or alternatively, according to examples as disclosed herein, the communication manager 620 may support wireless communication at the second UE. The beam failure receiving component 640 may be configured to or otherwise support components for receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The beam failure sending component 645 may be configured to or otherwise support components for sending the beam failure recovery message to the network entity via an uplink communication link.

[0149] In some examples, the feedback message sending component 670 may be configured as or otherwise support a component for sending a feedback message to the first UE in response to receiving a beam failure recovery message, the feedback message indicating that the beam failure recovery message was successfully received at the second UE.

[0150] In some examples, the feedback message receiving component 675 may be configured or otherwise support a component for receiving a first feedback message from a network entity in response to the beam failure recovery message, the first feedback message indicating that the beam failure recovery message was successfully received at the network entity. In some examples, the feedback message sending component 670 may be configured or otherwise support a component for sending a second feedback message to a second UE in response to receiving the first feedback message, the second feedback message indicating that the beam failure recovery message was successfully received at the network entity.

[0151] Figure 7 A diagram of a system 700 including a device 705 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 705 may be an example of a device 405, a device 505, or a UE 115 as described herein or include components thereof. The device 705 may communicate (e.g., wirelessly) with one or more network entities 105, one or more UEs 115, or any combination thereof. The device 705 may include components for two-way voice and data communications, including components for sending and receiving communications, such as a communication manager 720, an input / output (I / O) controller 710, a transceiver 715, an antenna 725, a memory 730, a code 735, and a processor 740. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 745).

[0152] I / O controller 710 can manage input signals and output signals of device 705. I / O controller 710 can also manage peripheral devices that are not integrated into device 705. In some cases, I / O controller 710 can represent a physical connection or port to an external peripheral device. In some cases, I / O controller 710 can utilize an operating system, such as or another known operating system. Additionally or alternatively, I / O controller 710 may represent or interact with a modem, keyboard, mouse, touch screen, or similar device. In some cases, I / O controller 710 may be implemented as part of a processor (such as processor 740). In some cases, a user may interact with device 705 via I / O controller 710 or via hardware components controlled by I / O controller 710.

[0153] In some cases, the device 705 may include a single antenna 725. However, in some other cases, the device 705 may have more than one antenna 725, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 715 may communicate bidirectionally via one or more antennas 725, a wired or wireless link, as described herein. For example, the transceiver 715 may represent a wireless transceiver and may communicate bidirectionally with another wireless transceiver. The transceiver 715 may also include a modem for modulating packets, providing the modulated packets to one or more antennas 725 for transmission, and for demodulating packets received from one or more antennas 725. The transceiver 715 or the transceiver 715 and the one or more antennas 725 may be examples of transmitters 415, transmitters 515, receivers 410, receivers 510, or any combination thereof or components thereof as described herein.

[0154] The memory 730 may include random access memory (RAM) and read-only memory (ROM). The memory 730 may store computer-readable, computer-executable code 735 including instructions that, when executed by the processor 740, cause the device 705 to perform various functions described herein. The code 735 may be stored in a non-transitory computer-readable medium, such as a system memory or another type of memory. In some cases, the code 735 may not be directly executable by the processor 740, but may (e.g., when compiled and executed) cause the computer to perform the functions described herein. In some cases, the memory 730 may also include, among other things, a basic I / O system (BIOS) that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0155] The processor 740 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, a CPU, a microcontroller, an ASIC, an FPGA, a programmable logic device, a discrete gate or transistor logic component, a discrete hardware component, or any combination thereof). In some cases, the processor 740 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 740. The processor 740 may be configured to execute computer-readable instructions stored in a memory (e.g., a memory 730) so that the device 705 performs various functions (e.g., functions or tasks that support techniques for beam failure recovery in multipath communications). For example, the device 705 or a component of the device 705 may include a processor 740 and a memory 730 coupled to or coupled to the processor 740, and the processor 740 and the memory 730 are configured to perform the various functions described herein.

[0156] According to examples as disclosed herein, the communication manager 720 may support wireless communications at the first UE. For example, the communication manager 720 may be configured to or otherwise support components for communicating with a network entity using one or more directional beams. The communication manager 720 may be configured to or otherwise support components for calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The communication manager 720 may be configured to or otherwise support components for sending a beam failure recovery message to a network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0157] Additionally or alternatively, according to examples as disclosed herein, the communication manager 720 may support wireless communication at the second UE. For example, the communication manager 720 may be configured to or otherwise support components for receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The communication manager 720 may be configured to or otherwise support components for sending the beam failure recovery message to the network entity via an uplink communication link.

[0158] By including or configuring the communication manager 720 according to the examples described herein, the device 705 can support techniques for improving communication reliability, reducing latency, more efficiently utilizing communication resources, and improving coordination between devices. For example, by using a sidelink communication link with another UE to perform BFR techniques, the processor of the device 705 can more efficiently send BFR messages and communicate with network entities.

[0159] In some examples, the communication manager 720 may be configured to perform various operations (e.g., receive, monitor, transmit) using or otherwise cooperating with the transceiver 715, one or more antennas 725, or any combination thereof. Although the communication manager 720 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 720 may be supported or performed by the processor 740, the memory 730, the code 735, or any combination thereof. For example, the code 735 may include instructions executable by the processor 740 to cause the device 705 to perform various aspects of the techniques for beam failure recovery in multipath communications as described herein, or the processor 740 and the memory 730 may be otherwise configured to perform or support such operations.

[0160] Figure 8A block diagram 800 of a device 805 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 805 may be an example of aspects of the network entity 105 as described herein. The device 805 may include a receiver 810, a transmitter 815, and a communication manager 820. The device 805 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0161] The receiver 810 may provide means for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of the device 805. In some examples, the receiver 810 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 810 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof.

[0162] The transmitter 815 may provide a means for outputting (e.g., sending, providing, conveying, transmitting) information generated by other components of the device 805. For example, the transmitter 815 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 815 may support outputting information by sending signals via one or more antennas. Additionally or alternatively, the transmitter 815 may support outputting information by sending signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 815 and the receiver 810 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0163] The communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or various components thereof, may be examples of means for performing various aspects of the techniques for beam failure recovery in multipath communications as described herein. For example, the communication manager 820, the receiver 810, the transmitter 815, or various combinations thereof, or components thereof, may support methods for performing one or more of the functions described herein.

[0164] In some examples, the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be implemented in hardware (e.g., in a communication management circuit). The hardware may include a processor, a DSP, a CPU, an ASIC, an FPGA or other programmable logic device, a microcontroller, discrete gate or transistor logic, discrete hardware components, or any combination thereof that is configured as or otherwise supports components for performing the functions described in the present disclosure. In some examples, a processor and a memory coupled to the processor may be configured to perform one or more of the functions described herein (e.g., by executing instructions stored in the memory by the processor).

[0165] Additionally or alternatively, in some examples, the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be implemented in code executed by a processor (e.g., as communication management software or firmware). If implemented in code executed by a processor, the functionality of the communication manager 820, the receiver 810, the transmitter 815, or various combinations or components thereof may be performed by a general purpose processor (e.g., configured as or otherwise supporting components for performing the functions described in the present disclosure), a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices.

[0166] In some examples, the communication manager 820 can be configured to perform various operations (e.g., receive, obtain, monitor, output, send) using or otherwise cooperating with the receiver 810, the transmitter 815, or both. For example, the communication manager 820 can receive information from the receiver 810, transmit information to the transmitter 815, or integrate with the receiver 810, the transmitter 815, or both to obtain information, output information, or perform various other operations as described herein.

[0167] According to examples as disclosed herein, the communication manager 820 may support wireless communications at a network entity. For example, the communication manager 820 may be configured to or otherwise support components for communicating with a first UE using one or more directional beams. The communication manager 820 may be configured to or otherwise support components for receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether the duration between the detected beam failure and the random access opportunity satisfies a threshold duration.

[0168] By including or configuring the communication manager 820 according to the examples described herein, the device 805 (e.g., a processor controlling the receiver 810, the transmitter 815, the communication manager 820, or a combination thereof or otherwise coupled thereto) can support techniques for reducing power consumption and more efficiently utilizing communication resources. For example, by performing BFR techniques using a sidelink communication link with another UE, the processor of the device 805 can more efficiently send BFR messages and communicate with network entities.

[0169] Fig. 9 A block diagram 900 of a device 905 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 905 may be an example of aspects of the device 805 or the network entity 105 as described herein. The device 905 may include a receiver 910, a transmitter 915, and a communication manager 920. The device 905 may also include a processor. Each of these components may communicate with each other (e.g., via one or more buses).

[0170] The receiver 910 may provide means for obtaining (e.g., receiving, determining, identifying) information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). The information may be passed to other components of the device 905. In some examples, the receiver 910 may support obtaining information by receiving signals via one or more antennas. Additionally or alternatively, the receiver 910 may support obtaining information by receiving signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof.

[0171] The transmitter 915 may provide a means for outputting (e.g., sending, providing, conveying, transmitting) information generated by other components of the device 905. For example, the transmitter 915 may output information associated with various channels (e.g., control channels, data channels, information channels, channels associated with a protocol stack), such as user data, control information, or any combination thereof (e.g., I / Q samples, symbols, packets, protocol data units, service data units). In some examples, the transmitter 915 may support outputting information by sending signals via one or more antennas. Additionally or alternatively, the transmitter 915 may support outputting information by sending signals via one or more wired (e.g., electrical, optical) interfaces, wireless interfaces, or any combination thereof. In some examples, the transmitter 915 and the receiver 910 may be co-located in a transceiver, which may include a modem or be coupled to a modem.

[0172] The device 905 or its various components may be examples of components for performing various aspects of the technology for beam failure recovery in multipath communication as described herein. For example, the communication manager 920 may include a beam communication component 925, a beam failure recovery receiving component 930, or any combination thereof. The communication manager 920 may be an example of various aspects of the communication manager 820 as described herein. In some examples, the communication manager 920 or its various components may be configured to use or otherwise cooperate with the receiver 910, the transmitter 915, or both to perform various operations (e.g., receive, obtain, monitor, output, send). For example, the communication manager 920 may receive information from the receiver 910, transmit information to the transmitter 915, or be integrated with the receiver 910, the transmitter 915, or both to obtain information, output information, or perform various other operations as described herein.

[0173] According to examples as disclosed herein, the communication manager 920 may support wireless communications at a network entity. The beam communication component 925 may be configured to or otherwise support components for communicating with a first UE using one or more directional beams. The beam failure recovery receiving component 930 may be configured to or otherwise support components for receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether the duration between the detected beam failure and the random access opportunity satisfies a threshold duration.

[0174] Fig.10A block diagram 1000 of a communication manager 1020 supporting techniques for beam failure recovery in multipath communications in accordance with one or more aspects of the present disclosure is shown. The communication manager 1020 may be an example of aspects of the communication manager 820, the communication manager 920, or both as described herein. The communication manager 1020 or its various components may be examples of components for performing various aspects of the techniques for beam failure recovery in multipath communications as described herein. For example, the communication manager 1020 may include a beam communication component 1025, a beam failure recovery receiving component 1030, a random access receiving component 1035, a request message receiving component 1040, a control message sending component 1045, a downlink message sending component 1050, a random access response sending component 1055, or any combination thereof. Each of these components may communicate directly or indirectly with each other (e.g., via one or more buses), which communication may include communication within a protocol layer of a protocol stack, communication associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack, within a device, component, or virtualized component associated with the network entity 105, between devices, components, or virtualized components associated with the network entity 105), or any combination thereof.

[0175] According to examples as disclosed herein, the communication manager 1020 may support wireless communications at a network entity. The beam communication component 1025 may be configured to or otherwise support components for communicating with a first UE using one or more directional beams. The beam failure recovery receiving component 1030 may be configured to or otherwise support components for receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0176] In some examples, to support receiving a beam failure recovery message, the beam failure recovery receiving component 1030 may be configured to or otherwise support a component for receiving a beam failure recovery message from a second UE based on the duration failing to satisfy a threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the first UE. In some examples, the downlink message sending component 1050 may be configured to or otherwise support a component for sending a downlink message to the first UE via the first directional beam and in response to receiving the beam failure recovery message, the downlink message scheduling one or more uplink transmissions.

[0177] In some examples, to support receiving a beam failure recovery message, the random access receiving component 1035 may be configured to or otherwise support a component for receiving a random access message from the first UE via a directional beam from a candidate directional beam set based on the duration satisfying a threshold duration, the random access message including the beam failure recovery message. In some examples, the random access response sending component 1055 may be configured to or otherwise support a component for sending a random access response to the first UE based on the random access message, and the beam communication component 1025 may be configured to or otherwise support a component for communicating with the first UE using a directional beam different from at least one directional beam associated with the detected beam failure.

[0178] In some examples, request message receiving component 1040 may be configured or otherwise support means for receiving a request message from a first UE via a sidelink communication link with one or more other UEs, the request message indicating a request to perform a beam failure recovery procedure. In some examples, control message sending component 1045 may be configured or otherwise support means for sending a control message to activate a beam failure recovery procedure to the first UE via a sidelink communication link with one or more other UEs, wherein the beam failure recovery message is received from a second UE based on sending the control message.

[0179] Fig.11 A diagram of a system 1100 including a device 1105 supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure is shown. The device 1105 may be an example of a device 805, a device 905, or a network entity 105 as described herein or include components thereof. The device 1105 may communicate with one or more network entities 105, one or more UEs 115, or any combination thereof, which may include communication through one or more wired interfaces, through one or more wireless interfaces, or any combination thereof. The device 1105 may include components that support output and receive communications, such as a communication manager 1120, a transceiver 1110, an antenna 1115, a memory 1125, a code 1130, and a processor 1135. These components may be electronically communicated or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., bus 1140).

[0180] As described herein, the transceiver 1110 may support bidirectional communication via a wired link, a wireless link, or both. In some examples, the transceiver 1110 may include a wired transceiver and may communicate bidirectionally with another wired transceiver. Additionally or alternatively, in some examples, the transceiver 1110 may include a wireless transceiver and may communicate bidirectionally with another wireless transceiver. In some examples, the device 1105 may include one or more antennas 1115, which may be capable of (e.g., concurrently) sending or receiving wireless transmissions. The transceiver 1110 may also include a modem for modulating a signal, for providing a modulated signal for transmission (e.g., through one or more antennas 1115, through a wired transmitter), for receiving a modulated signal (e.g., from one or more antennas 1115, from a wired receiver), and for demodulating the signal. In some implementations, the transceiver 1110 may include one or more interfaces, such as one or more interfaces coupled to one or more antennas 1115 configured to support various receiving or obtaining operations, or one or more interfaces coupled to one or more antennas 1115 configured to support various transmitting or outputting operations, or a combination thereof. In some implementations, the transceiver 1110 may include or be configured to be coupled to one or more processors or memory components, which are operable to perform the following actions: perform or support operations based on received or obtained information or signals, or generate information or other signals for transmission or other output, or any combination of these operations. In some implementations, the transceiver 1110 or the transceiver 1110 and one or more antennas 1115 or the transceiver 1110 and one or more antennas 1115 and one or more processors or memory components (e.g., processor 1135 or memory 1125 or both) may be included in a chip or chip component installed in the device 1105. In some examples, the transceiver may be operable to support communications via one or more communication links (eg, communication link 125, backhaul communication link 120, midhaul communication link 162, fronthaul communication link 168).

[0181] Memory 1125 may include RAM and ROM. Memory 1125 may store computer-readable, computer-executable code 1130 including instructions that, when executed by processor 1135, cause device 1105 to perform various functions described herein. Code 1130 may be stored in a non-transitory computer-readable medium, such as system memory or another type of memory. In some cases, code 1130 may not be directly executable by processor 1135, but may (e.g., when compiled and executed) cause a computer to perform the functions described herein. In some cases, memory 1125 may include, among other things, a BIOS that may control basic hardware or software operations, such as interaction with peripheral components or devices.

[0182] The processor 1135 may include an intelligent hardware device (e.g., a general-purpose processor, a DSP, an ASIC, a CPU, an FPGA, a microcontroller, a programmable logic device, a discrete gate or transistor logic element, a discrete hardware component, or any combination thereof). In some cases, the processor 1135 may be configured to operate a memory array using a memory controller. In some other cases, the memory controller may be integrated into the processor 1135. The processor 1135 may be configured to execute computer-readable instructions stored in a memory (e.g., memory 1125) so that the device 1105 performs various functions (e.g., functions or tasks that support techniques for beam failure recovery in multipath communications). For example, the device 1105 or a component of the device 1105 may include a processor 1135 and a memory 1125 coupled to the processor 1135, and the processor 1135 and the memory 1125 are configured to perform the various functions described herein. The processor 1135 may be an example of a cloud computing platform (e.g., one or more physical nodes and supporting software, such as an operating system, a virtual machine, or a container instance) that can host functions (e.g., by executing code 1130) to perform functions of the device 1105. The processor 1135 may be any one or more suitable processors capable of executing scripts or instructions of one or more software programs stored in the device 1105 (such as in the memory 1125). In some specific implementations, the processor 1135 may be a component of a processing system. A processing system may generally refer to a system or a series of machines or components that receive inputs and process these inputs to produce a set of outputs (which may be delivered to, for example, other systems or components of the device 1105). For example, the processing system of the device 1105 may refer to a system including various other components or subcomponents of the device 1105, such as the processor 1135, or the transceiver 1110, or the communication manager 1120, or other components or combinations of components of the device 1105. The processing system of device 1105 can interface with other components of device 1105, and can process information (such as input or signal) received from other components or output information to other components. For example, a chip or modem of device 1105 may include a processing system and one or more interfaces for outputting information or for obtaining information or both. One or more interfaces may be implemented as or otherwise include a first interface configured to output information and a second interface configured to obtain information or the same interface configured to output information and obtain information, as well as other specific implementations. In some specific implementations, one or more interfaces may refer to an interface between a processing system of a chip or modem and a transmitter, so that device 1105 can send information output from the chip or modem.Additionally or alternatively, in some implementations, one or more interfaces may refer to an interface between a processing system of a chip or modem and a receiver, such that the device 1105 may obtain information or signal input, and the information may be passed to the processing system. One of ordinary skill in the art will readily recognize that a first interface may also obtain information or signal input, and a second interface may also output information or signal output.

[0183] In some examples, bus 1140 may support communications of a protocol layer (e.g., within a protocol layer) of a protocol stack. In some examples, bus 1140 may support communications associated with a logical channel of a protocol stack (e.g., between protocol layers of a protocol stack), which may include communications performed within a component of device 1105, or communications performed between different components of device 1105 that may be co-located or located in different locations (e.g., where device 1105 may refer to a system in which one or more of communication manager 1120, transceiver 1110, memory 1125, code 1130, and processor 1135 may be located in one of the different components or divided between the different components).

[0184] In some examples, the communication manager 1120 can manage aspects of communications with the core network 130 (e.g., via one or more wired or wireless backhaul links). For example, the communication manager 1120 can manage the delivery of data communications for client devices, such as one or more UEs 115. In some examples, the communication manager 1120 can manage communications with other network entities 105 and can include a controller or scheduler for controlling communications with the UE 115 in coordination with the other network entities 105. In some examples, the communication manager 1120 can support an X2 interface within an LTE / LTE-A wireless communication network technology to provide communications between network entities 105.

[0185] According to examples as disclosed herein, the communication manager 1120 may support wireless communications at a network entity. For example, the communication manager 1120 may be configured to or otherwise support components for communicating with a first UE using one or more directional beams. The communication manager 1120 may be configured to or otherwise support components for receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based on whether the duration between the detected beam failure and the random access opportunity satisfies a threshold duration.

[0186] By including or configuring the communication manager 1120 according to the examples described herein, the device 1105 can support techniques for improving communication reliability, reducing latency, more efficiently utilizing communication resources, and improving coordination between devices. For example, by using a sidelink communication link with another UE to perform BFR techniques, the processor of the device 1105 can more efficiently send BFR messages and communicate with network entities.

[0187] In some examples, the communication manager 1120 may be configured to perform various operations (e.g., receive, obtain, monitor, output, transmit) using or otherwise cooperating with the transceiver 1110, one or more antennas 1115 (e.g., where applicable), or any combination thereof. Although the communication manager 1120 is illustrated as a separate component, in some examples, one or more functions described with reference to the communication manager 1120 may be supported or performed by the transceiver 1110, the processor 1135, the memory 1125, the code 1130, or any combination thereof. For example, the code 1130 may include instructions that are executable by the processor 1135 to cause the device 1105 to perform various aspects of the techniques for beam failure recovery in multipath communications as described herein, or the processor 1135 and the memory 1125 may be otherwise configured to perform or support such operations.

[0188] Fig.12 A flowchart is shown that illustrates a method 1200 for supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1200 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1200 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 7 The described UE 115 performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0189] At 1205, the method may include: communicating with a network entity using one or more directional beams. The operations of 1205 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1205 may be performed as described in reference to Figure 6 The beam communication component 625 is described to perform.

[0190] At 1210, the method may include: calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The operations of 1210 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1210 may be described with reference to Figure 6The beam failure calculation component 630 is described to perform.

[0191] At 1215, the method may include: sending a beam failure recovery message to a network entity or to a second UE based on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure. The operations of 1215 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1215 may be performed as described in reference to Figure 6 The beam fault sending component 635 executes.

[0192] Fig.13 A flowchart is shown that illustrates a method 1300 of supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1300 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1300 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 7 The described UE 115 performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0193] At 1305, the method may include: communicating with a network entity using one or more directional beams. The operations of 1305 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1305 may be performed as described in reference to Figure 6 The beam communication component 625 is described to perform.

[0194] At 1310, the method may include: calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The operations of 1310 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1310 may be described with reference to Figure 6 The beam failure calculation component 630 is described to perform.

[0195] At 1315, the method may include: sending a beam failure recovery message to the second UE via the sidelink communication link based on the calculated duration failing to satisfy the threshold duration, the beam failure recovery message indicating the detected beam failure, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the network entity. The operations of 1315 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1315 may be performed as described in reference to Figure 6 The beam fault sending component 635 executes.

[0196] Fig.14A flowchart is shown that illustrates a method 1400 of supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1400 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1400 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 7 The described UE 115 performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0197] At 1405, the method may include: communicating with a network entity using one or more directional beams. The operations of 1405 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1405 may be performed as described in reference to Figure 6 The beam communication component 625 is described to perform.

[0198] At 1410, the method may include: calculating a duration between a detected beam failure and a random access opportunity based on detecting a beam failure associated with at least one of the one or more directional beams. The operations of 1410 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1410 may be performed as described in reference to Figure 6 The beam selection component 650 is described as performing.

[0199] At 1415, the method may include: selecting a directional beam from a set of one or more candidate directional beams. The operations of 1415 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1415 may be performed as described in reference to Figure 6 The beam fault sending component 635 executes.

[0200] At 1420, the method may include: sending a random access message to a network entity via the selected directional beam based on the duration satisfying the threshold duration, the random access message including a beam failure recovery message. The operations of 1420 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1420 may be performed as described in reference to Figure 6 The beam fault sending component 635 executes.

[0201] Fig.15 A flowchart is shown that illustrates a method 1500 for supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1500 may be implemented by a network entity or a component thereof as described herein. For example, the operations of the method 1500 may be implemented by a network entity or a component thereof as described in reference to Figure 1 To Figure 3 and Figures 8 to 11The described network entity performs. In some examples, the network entity may execute an instruction set to control the functional elements of the network entity to perform the described functions. Additionally or alternatively, the network entity may use dedicated hardware to perform various aspects of the described functions.

[0202] At 1505, the method may include: communicating with the first UE using one or more directional beams. The operations of 1505 may be performed according to examples disclosed herein. In some examples, aspects of the operations of 1505 may be performed as described in reference to Fig.10 The beam communication component 1025 performs as described.

[0203] At 1510, the method may include: receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from a first UE or from a second UE different from the first UE based on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration. The operations of 1510 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1510 may be performed as described in reference to Fig.10 The beam failure recovery receiving component 1030 is described to perform.

[0204] Fig.16 A flowchart is shown that illustrates a method 1600 of supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1600 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1600 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 7 The described UE 115 performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0205] At 1605, the method may include: receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The operations of 1605 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed by reference to Figure 6 The beam failure receiving component 640 is described to perform.

[0206] At 1610, the method may include: sending a beam failure recovery message to a network entity via an uplink communication link. The operations of 1610 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1610 may be described with reference to Figure 6The beam failure transmission component 645 is described to perform.

[0207] Fig.17 A flowchart is shown that illustrates a method 1700 of supporting techniques for beam failure recovery in multipath communications according to one or more aspects of the present disclosure. The operations of the method 1700 may be implemented by a UE or a component thereof as described herein. For example, the operations of the method 1700 may be implemented by a UE or a component thereof as described in reference to Figures 1 to 7 The described UE 115 performs. In some examples, the UE may execute an instruction set to control the functional elements of the UE to perform the described functions. Additionally or alternatively, the UE may use dedicated hardware to perform various aspects of the described functions.

[0208] At 1705, the method may include: receiving a beam failure recovery message from the first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and the network entity. The operations of 1705 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed by reference to Figure 6 The beam failure receiving component 640 is described to perform.

[0209] At 1710, the method may include: in response to receiving the beam failure recovery message, sending a feedback message to the first UE, the feedback message indicating that the beam failure recovery message was successfully received at the second UE. The operations of 1710 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed as described in reference to Figure 6 The described feedback message sending component 670 executes.

[0210] At 1715, the method may include: sending a beam failure recovery message to a network entity via an uplink communication link. The operations of 1715 may be performed according to examples as disclosed herein. In some examples, aspects of the operations of 1715 may be described with reference to Figure 6 The beam failure transmission component 645 is described to perform.

[0211] The following provides an overview of various aspects of the disclosure:

[0212] Aspect 1: A method for performing wireless communications at a first UE, the method comprising: communicating with a network entity using one or more directional beams; calculating a duration between a detected beam failure and a random access opportunity based at least in part on detecting a beam failure associated with at least one of the one or more directional beams; and sending a beam failure recovery message to the network entity or to a second UE based at least in part on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

[0213] Aspect 2: A method according to Aspect 1, wherein sending the beam failure recovery message includes: sending the beam failure recovery message to the second UE via a side link communication link based at least in part on the calculated duration failing to meet the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the network entity.

[0214] Aspect 3: According to the method described in Aspect 2, the method also includes: starting a timer based at least in part on sending the beam failure recovery message to the second UE; and monitoring the first directional beam for one or more downlink messages from the network entity based at least in part on starting the timer.

[0215] Aspect 4: According to the method described in Aspect 3, the method also includes: sending a random access message to the network entity based at least in part on the expiration of the timer before receiving the one or more downlink messages via the first directional beam; and communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based at least in part on sending the random access message to the network entity.

[0216] Aspect 5: The method according to any one of Aspects 3 to 4, wherein the timer is started when the beam failure recovery message is sent to the second UE.

[0217] Aspect 6: According to the method described in any one of Aspects 3 to 4, the method further includes: receiving a feedback message from the second UE in response to the beam failure recovery message, indicating that the beam failure recovery message is successfully received at the second UE, wherein the timer is started when the feedback message is received from the second UE.

[0218] Aspect 7: According to the method described in any one of Aspects 3 to 4, the method further includes: receiving a feedback message from the second UE in response to the beam failure recovery message, indicating that the beam failure recovery message is successfully received at the network entity, wherein the timer is started when the feedback message is received from the second UE.

[0219] Aspect 8: A method according to Aspect 1, wherein sending the beam failure recovery message comprises: selecting a directional beam from a set of one or more candidate directional beams; and sending a random access message to the network entity via the selected directional beam based at least in part on the duration satisfying the threshold duration, the random access message including the beam failure recovery message.

[0220] Aspect 9: According to the method described in Aspect 8, the method also includes: starting a timer when sending the random access message to the network entity; and monitoring a random access response from the network entity based at least in part on one or more measurement resources and at least in part on starting the timer.

[0221] Aspect 10: According to the method described in Aspect 9, the method also includes: sending an additional beam failure recovery message to the second UE via a side link communication link at least in part based on the timer expiring before receiving the random access response, wherein the beam failure recovery message includes a request for beam refinement associated with the directional beam; and communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based at least in part on sending the additional beam failure recovery message to the second UE.

[0222] Aspect 11: According to the method described in any one of Aspects 1 to 10, the method further includes: receiving a control message indicating the configuration of the threshold duration from the network entity, the threshold duration being based at least in part on access link channel conditions, side link channel conditions, capabilities of the UE, or any combination thereof.

[0223] Aspect 12: According to the method described in any one of Aspects 1 to 11, the method further includes: receiving a control message for activating a beam failure recovery procedure from the network entity via a side link communication link with the second UE, wherein sending the beam failure recovery message to the network entity or to the second UE is at least partially based on whether the calculated duration satisfies the threshold duration and is at least partially based on receiving the control message.

[0224] Aspect 13: According to the method described in any one of Aspects 1 to 12, the method further includes: sending a request message to the network entity via the sidelink communication link with the second UE, the request message including a request to execute the beam failure recovery procedure, wherein receiving the control message for activating the beam failure recovery procedure using the second UE is at least partially based on sending the request message.

[0225] Aspect 14: A method for performing wireless communications at a network entity, the method comprising: communicating with a first UE using one or more directional beams; and receiving a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based at least in part on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

[0226] Aspect 15: A method according to Aspect 14, wherein receiving the beam failure recovery message includes: receiving the beam failure recovery message from the second UE based at least in part on the duration failing to satisfy the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the first UE, and the method further includes: sending a downlink message to the first UE via the first directional beam and in response to receiving the beam failure recovery message, the downlink message scheduling one or more uplink transmissions.

[0227] Aspect 16: A method according to Aspect 14, wherein receiving the beam failure recovery message includes: receiving a random access message from the first UE via a directional beam from a candidate directional beam set based at least in part on the duration satisfying the threshold duration, the random access message including the beam failure recovery message, the method also includes: sending a random access response to the first UE based at least in part on the random access message; and communicating with the first UE using a directional beam different from the at least one directional beam associated with the detected beam failure.

[0228] Aspect 17: According to the method described in any one of Aspects 14 to 16, the method further includes: receiving a request message from the first UE via a sidelink communication link with one or more other UEs, the request message indicating a request to perform a beam failure recovery procedure; and sending a control message to the first UE via the sidelink communication link with the one or more other UEs to activate the beam failure recovery procedure, wherein the beam failure recovery message is received from the second UE at least in part based on sending the control message.

[0229] Aspect 18: A method for performing wireless communications at a second UE, the method comprising: receiving a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communication between the first UE and a network entity; and sending the beam failure recovery message to the network entity via an uplink communication link.

[0230] Aspect 19: According to the method according to Aspect 18, the method also includes: sending a feedback message to the first UE in response to receiving the beam failure recovery message, and the feedback message indicates that the beam failure recovery message is successfully received at the second UE.

[0231] Aspect 20: According to the method described in Aspect 18, the method also includes: receiving a first feedback message from the network entity in response to the beam failure recovery message, the first feedback message indicating that the beam failure recovery message is successfully received at the network entity; and sending a second feedback message to the second UE in response to receiving the first feedback message, the second feedback message indicating that the beam failure recovery message is successfully received at the network entity.

[0232] Aspect 21: An apparatus for performing wireless communications at a first UE, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to any one of Aspects 1 to 13.

[0233] Aspect 22: An apparatus for wireless communication at a first UE, the apparatus comprising: at least one component for performing a method according to any one of aspects 1 to 13.

[0234] Aspect 23: A non-transitory computer-readable medium storing a code for wireless communication at a first UE, the code comprising instructions executable by a processor to perform a method according to any one of aspects 1 to 13.

[0235] Aspect 24: An apparatus for wireless communication at a network entity, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to any one of Aspects 14 to 17.

[0236] Aspect 25: An apparatus for wireless communication at a network entity, the apparatus comprising at least one component for performing a method according to any one of aspects 14 to 17.

[0237] Aspect 26: A non-transitory computer-readable medium storing code for wireless communication at a network entity, the code comprising instructions executable by a processor to perform the method according to any one of aspects 14 to 17.

[0238] Aspect 27: An apparatus for performing wireless communications at a second UE, the apparatus comprising: a processor; a memory coupled to the processor; and instructions stored in the memory and executable by the processor to cause the apparatus to perform a method according to any one of Aspects 18 to 20.

[0239] Aspect 28: An apparatus for wireless communication at a second UE, the apparatus comprising: at least one component for performing a method according to any one of aspects 18 to 20.

[0240] Aspect 29: A non-transitory computer-readable medium storing code for wireless communication at a second UE, the code comprising instructions executable by a processor to perform the method according to any one of aspects 18 to 20.

[0241] It should be noted that the methods described herein describe possible implementations, and that the operations and steps may be rearranged or otherwise modified and other implementations are possible. In addition, aspects from two or more methods may be combined.

[0242] Although aspects of LTE, LTE-A, LTE-A Pro, or NR systems may be described for example purposes, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein may also be applicable to networks other than LTE, LTE-A, LTE-A Pro, or NR networks. For example, the techniques described may be applicable to various other wireless communication systems, such as Ultra Mobile Broadband (UMB), Institute of Electrical and Electronics Engineers (IEEE) 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM, and other systems and radio technologies not explicitly mentioned herein.

[0243] The information and signals described herein may be represented using any of a variety of different techniques and methods. For example, data, instructions, commands, information, signals, bits, symbols, and chips mentioned throughout the specification may be represented by voltage, current, electromagnetic waves, magnetic fields or magnetic particles, optical fields or optical particles, or any combination thereof.

[0244] The various illustrative blocks and components described in conjunction with the disclosure herein may be implemented or performed using a general purpose processor, DSP, ASIC, CPU, 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 may be a microprocessor, but in an alternative, the processor may be any processor, controller, microcontroller, or state machine. The processor may also be implemented as a combination of computing devices (e.g., a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration).

[0245] The functions described herein can be implemented using hardware, software executed by a processor, firmware, or any combination thereof. When implemented using software executed by a processor, the functions can be stored as one or more instructions or codes of a computer-readable medium, or sent using one or more instructions or codes of a computer-readable medium. Other examples and specific implementations are within the scope of the present disclosure and the appended claims. For example, due to the nature of software, the functions described herein can be implemented using software executed by a processor, hardware, firmware, hard wiring, or a combination of any of these items. Features that implement the functions can also be physically located at different locations, including being distributed so that the various parts of the functions are implemented at different physical locations.

[0246] Computer-readable medium includes both non-transient computer storage medium and communication medium, and it includes any medium that facilitates computer program to be transmitted from one position to another position.Non-transient storage medium can be any available medium that can be accessed by general or special-purpose computer.By way of example and not limitation, non-transient computer-readable medium can include RAM, ROM, electrically erasable programmable ROM (EEPROM), flash memory, compact disc (CD) ROM or other optical disc storage device, disk storage device or other magnetic storage device or can be used for carrying or storing desired program code parts and any other non-transient medium that can be accessed by general or special-purpose computer or general or special-purpose processor in the form of instruction or data structure.Moreover, any connection is appropriately referred to as computer-readable medium.For example, if software is sent from website, server or other remote source using coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) or wireless technology such as infrared, radio and microwave, then coaxial cable, fiber optic cable, twisted pair, DSL or wireless technology such as infrared, radio and microwave are included in the definition of computer-readable medium. Disks and optical disks as used herein include CDs, laser optical disks, optical optical disks, digital versatile disks (DVDs), floppy disks, and Blu-ray disks. Disks can reproduce data magnetically, while optical disks can reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media.

[0247] As used herein (including in the claims), "or" used in a list of items (e.g., a list of items followed by a phrase such as "at least one of" or "one or more of") indicates an inclusive list, so that, for example, a list of at least one of A, B, or C means A or B or C or AB or AC or BC or ABC (i.e., A and B and C). In addition, as used herein, the phrase "based on" should not be interpreted as a reference to a closed set of conditions. For example, an example step described as "based on condition A" can be based on both condition A and condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase "based on" should be interpreted in the same manner as the phrase "based at least in part on."

[0248] The terms "determine" or "determining" encompass a variety of actions, and thus, "determining" may include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, database or other data structure), ascertaining, and the like. Furthermore, "determining" may include receiving (e.g., receiving information), accessing (e.g., accessing data stored in a memory), etc. Additionally, "determining" may include parsing, obtaining, selecting, choosing, establishing, and other such similar actions.

[0249] In the drawings, similar components or features may have the same reference label. In addition, various components of the same type may be distinguished by following the reference label with a dash and a second label to distinguish between similar components. If only the first reference label is used in the specification, the description may apply to any of the similar components having the same first reference label, regardless of the second or other subsequent reference labels.

[0250] The descriptions set forth herein in conjunction with the accompanying drawings describe example configurations and do not represent all examples that may be implemented or within the scope of the claims. The term "example" as used herein means "used as an example, instance, or illustration," rather than "preferred" or "advantageous over other examples." The specific implementation includes specific details to provide an understanding of the described techniques. However, these techniques may be practiced without these specific details. In some cases, known structures and devices are shown in block diagram form to avoid obscuring the concepts of the described examples.

[0251] The description herein is provided to enable one of ordinary skill in the art to implement or use the present disclosure. Various modifications to the present disclosure will be apparent to one of ordinary skill in the art, and the general principles defined herein may be applied to other variations without departing from the scope of the present disclosure. Thus, the present disclosure is not limited to the examples and designs described herein, but should be granted the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An apparatus for wireless communication at a first user equipment (UE), the apparatus comprising: Memory; and a processor coupled to the memory and configured to: communicating with a network entity using one or more directional beams; calculating a duration between a detected beam failure and a random access opportunity based at least in part on detecting a beam failure associated with at least one of the one or more directional beams; as well as A beam failure recovery message is sent to the network entity or to a second UE based at least in part on whether the calculated duration satisfies a threshold duration, the beam failure recovery message indicating the detected beam failure.

2. The device according to claim 1, wherein: In order to send the beam failure recovery message, the processor is further configured to: The beam failure recovery message is sent to the second UE via a sidelink communication link based at least in part on the calculated duration failing to satisfy the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communications with the network entity.

3. The apparatus of claim 2, wherein the processor is further configured to: starting a timer based at least in part on sending the beam failure recovery message to the second UE; and The first directional beam is monitored for one or more downlink messages from the network entity based at least in part on starting the timer.

4. The apparatus of claim 3, wherein the processor is further configured to: sending a random access message to the network entity based at least in part on the timer expiring prior to receiving the one or more downlink messages via the first directional beam; and Communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based at least in part on sending the random access message to the network entity.

5. The apparatus according to claim 3, wherein the timer is started when the beam failure recovery message is sent to the second UE.

6. The apparatus of claim 3, wherein the processor is further configured to: In response to the beam failure recovery message, a feedback message is received from the second UE indicating that the beam failure recovery message is successfully received at the second UE, wherein the timer is started when the feedback message is received from the second UE.

7. The apparatus of claim 3, wherein the processor is further configured to: receiving a feedback message from the second UE in response to the beam failure recovery message indicating that the beam failure recovery message was successfully received at the network entity, wherein the timer is started when the feedback message is received from the second UE.

8. The device according to claim 1, wherein: In order to send the beam failure recovery message, the processor is further configured to: selecting a directional beam from a set of one or more candidate directional beams; and A random access message is sent to the network entity via the selected directional beam based at least in part on the duration satisfying the threshold duration, the random access message comprising the beam failure recovery message.

9. The apparatus of claim 8, wherein the processor is further configured to: Starting a timer when sending the random access message to the network entity; and Monitoring a random access response from the network entity is performed based at least in part on one or more measurement resources and based at least in part on starting the timer.

10. The apparatus of claim 9, wherein the processor is further configured to: sending an additional beam failure recovery message to the second UE via a sidelink communication link based at least in part on the timer expiring prior to receiving the random access response, wherein the beam failure recovery message includes a request for beam refinement associated with the directional beam; and Communicating with the network entity using a directional beam different from the at least one directional beam associated with the detected beam failure based at least in part on sending the additional beam failure recovery message to the second UE.

11. The apparatus of claim 1 , wherein the processor is further configured to: A control message is received from the network entity indicating configuration of the threshold duration, the threshold duration being based at least in part on access link channel conditions, side link channel conditions, capabilities of the UE, or any combination thereof.

12. The apparatus of claim 1, wherein the processor is further configured to: A control message for activating a beam failure recovery procedure is received from the network entity via a sidelink communication link with the second UE, wherein sending the beam failure recovery message to the network entity or to the second UE is based at least in part on whether the calculated duration satisfies the threshold duration and is based at least in part on receiving the control message.

13. The apparatus of claim 12, wherein the processor is further configured to cause the apparatus to: A request message is sent to the network entity via the sidelink communication link with the second UE, the request message including a request to execute the beam failure recovery procedure, wherein receiving the control message for activating the beam failure recovery procedure by the second UE is based at least in part on sending the request message.

14. An apparatus for wireless communication at a network entity, the apparatus comprising: Memory; and a processor coupled to the memory and configured to: communicating with a first user equipment (UE) using one or more directional beams; as well as Receive a beam failure recovery message indicating a detected beam failure associated with at least one of the one or more directional beams, wherein the beam failure recovery message is received from the first UE or from a second UE different from the first UE based at least in part on whether a duration between the detected beam failure and a random access opportunity satisfies a threshold duration.

15. The device according to claim 14, wherein: In order to receive the beam failure recovery message, the processor is further configured to: receiving the beam failure recovery message from the second UE based at least in part on the duration failing to satisfy the threshold duration, wherein the beam failure recovery message indicates a first directional beam for subsequent communication with the first UE, wherein the processor is further configured to: A downlink message is sent to the first UE via the first directional beam and in response to receiving the beam failure recovery message, the downlink message scheduling one or more uplink transmissions.

16. The device according to claim 14, wherein: In order to receive the beam failure recovery message, the processor is further configured to: receiving a random access message from the first UE via a directional beam from a set of candidate directional beams based at least in part on the duration satisfying the threshold duration, the random access message including the beam failure recovery message, wherein the processor is further configured to: sending a random access response to the first UE based at least in part on the random access message; and Communicating with the first UE using a directional beam different from the at least one directional beam associated with the detected beam failure.

17. The apparatus of claim 14, wherein the processor is further configured to: receiving a request message from the first UE via a sidelink communication link with one or more other UEs, the request message indicating a request to perform a beam failure recovery procedure; and Sending a control message activating the beam failure recovery procedure to the first UE via the sidelink communication link with the one or more other UEs, wherein the beam failure recovery message is received from the second UE based at least in part on sending the control message.

18. An apparatus for wireless communication at a second user equipment (UE), the apparatus comprising: Memory; and a processor coupled to the memory and configured to: receiving a beam failure recovery message from a first UE via a sidelink communication link, the beam failure recovery message indicating a detected beam failure associated with one or more directional beams used for communications between the first UE and a network entity; as well as The beam failure recovery message is sent to the network entity via an uplink communication link.

19. The apparatus of claim 18, wherein the processor is further configured to: In response to receiving the beam failure recovery message, a feedback message is sent to the first UE, the feedback message indicating that the beam failure recovery message is successfully received at the second UE.

20. The apparatus of claim 18, wherein the processor is further configured to: receiving a first feedback message from the network entity in response to the beam failure recovery message, the first feedback message indicating successful receipt of the beam failure recovery message at the network entity; and In response to receiving the first feedback message, a second feedback message is sent to the second UE, the second feedback message indicating that the beam failure recovery message is successfully received at the network entity.

Images