Synchronization signal block selection in an inter-cell wireless communications system
By employing RSRP threshold-based SSB selection techniques, the UE optimizes random access in inter-cell scenarios, addressing inefficiencies in conventional methods and enhancing the reliability of wireless communications.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- QUALCOMM INC
- Filing Date
- 2025-01-23
- Publication Date
- 2026-07-30
AI Technical Summary
Conventional SSB selection techniques used by user equipment (UE) are insufficient for inter-cell scenarios where SSBs are received from transmission-reception points (TRPs) with different physical cell identifiers and varying downlink capabilities, leading to inefficiencies in random access procedures.
The UE selects synchronization signal blocks (SSBs) based on reference signal received power (RSRP) thresholds and downlink capabilities, enabling improved random access preamble transmission in inter-cell scenarios through techniques like Option 1 to 8, which involve selecting between serving and non-serving cells, using PCI-specific RSRP thresholds, or following downlink control messages for SSB selection.
This approach enhances the UE's ability to select suitable random access resources, improving the efficiency and effectiveness of random access procedures in inter-cell wireless communications systems.
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Figure CN2025074185_30072026_PF_FP_ABST
Abstract
Description
SYNCHRONIZATION SIGNAL BLOCK SELECTION IN AN INTER-CELL WIRELESS COMMUNICATIONS SYSTEMFIELD OF TECHNOLOGY
[0001] The following relates to wireless communication, including synchronization signal block (SSB) selection in an inter-cell wireless communications system.BACKGROUND
[0002] Wireless communications systems are widely deployed to provide various types of communication content such as voice, video, packet data, messaging, broadcast, and so on. These systems may be capable of supporting communication with multiple users by sharing the available system resources (e.g., time, frequency, and power) . Examples of such multiple-access systems include fourth generation (4G) systems such as Long Term Evolution (LTE) systems, LTE-Advanced (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 technologies 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 communications system may include one or more base stations, each supporting wireless communication for communication devices, which may be known as user equipment (UE) .
[0003] A UE may use a random access procedure to establish a connection with a cell. Improved techniques for random access procedures may be desired.SUMMARY
[0004] The systems, methods, and devices of this disclosure each have several innovative aspects, no single one of which is solely responsible for the desirable attributes disclosed herein.
[0005] A method for wireless communications by a user equipment (UE) is described. The method may include receiving a first set of synchronization signal blocks (SSBs) associated with a serving cell that has a first physical cell identifier (PCI) , the first set of SSBs received from a first transmission-reception point (TRP) , receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP, selecting the first set of SSBs or the second set of SSBs based on one or more reference signal received power (RSRP) thresholds, and transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0006] A UE for wireless communications is described. The UE may include one or more memories storing processor executable code, and one or more processors coupled with the one or more memories. The one or more processors may individually or collectively be operable to execute the code to cause the UE to receive a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, receive a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP, select the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds, and transmit a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0007] Another UE for wireless communications is described. The UE may include means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, means for receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP, means for selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds, and means for transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on selecting the first set of SSBs or the second set of SSBs.
[0008] A non-transitory computer-readable medium storing code for wireless communications is described. The code may include instructions executable by one or more processors to receive a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, receive a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP, select the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds, and transmit a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0009] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more RSRP thresholds include a RSRP threshold associated with the serving cell and the one or more non-serving cells and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, the second set of SSBs, or both, where the first set of SSBs or the second set of SSBs may be selected based on the comparison.
[0010] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the one or more non-serving cells and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs and comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, where the first set of SSBs or the second set of SSBs may be selected based on the comparisons.
[0011] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more non-serving cells include a first non-serving cell and a second non-serving cell and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for selecting the first non-serving cell based on the selection of the second set of SSBs, where the SSB may be selected based on being associated with the first non-serving cell.
[0012] In some examples of the method, user equipment (UEs) , and non-transitory computer-readable medium described herein, the second set of SSBs may be associated with a first non-serving cell that may have a second PCI and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for receiving a third set of SSBs associated with a second non-serving cell that may have a third PCI and selecting the second set of SSBs from among the second set of SSBs and the third set of SSBs, where the first set of SSBs or the second set of SSBs may be selected based on the selection of the second set of SSBs.
[0013] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more RSRP thresholds include a RSRP threshold and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, where the first set of SSBs or the second set of SSBs may be selected based on the comparison.
[0014] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more RSRP thresholds include a RSRP threshold associated with the serving cell and the one or more non-serving cells and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs or the second set of SSBs, where the first set of SSBs or the second set of SSBs may be selected based on the comparison.
[0015] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the first non-serving cell and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs and comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, where the first set of SSBs or the second set of SSBs may be selected based on the comparisons.
[0016] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the one or more non-serving cells includes a non-serving cell that may have a second PCI and the one or more RSRP thresholds include a first RSRP threshold associated with the first PCI and a second RSRP threshold associated with the second PCI.
[0017] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the SSB may be of the first set of SSBs and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for determining that a RSRP metric associated with the SSB satisfies the first RSRP threshold, where the SSB may be selected based on the determination.
[0018] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the SSB may be of the second set of SSBs and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for determining that a RSRP metric associated with the SSB satisfies the second RSRP threshold, where the SSB may be selected based on the determination.
[0019] A method for wireless communications by a UE is described. The method may include receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receiving a downlink control information message triggering a random access procedure and indicating one or more of the first PCI or the second PCI, and transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the downlink control information message.
[0020] A UE for wireless communications is described. The UE may include one or more memories storing processor executable code, and one or more processors coupled with the one or more memories. The one or more processors may individually or collectively be operable to execute the code to cause the UE to receive a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, receive a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receive a downlink control information message triggering a random access procedure and indicating one or more of the first PCI or the second PCI, and transmit a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the downlink control information message.
[0021] Another UE for wireless communications is described. The UE may include means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, means for receiving a downlink control information message triggering a random access procedure and indicating one or more of the first PCI or the second PCI, and means for transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the downlink control information message.
[0022] A non-transitory computer-readable medium storing code for wireless communications is described. The code may include instructions executable by one or more processors to receive a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP, receive a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receive a downlink control information message triggering a random access procedure and indicating one or more of the first PCI or the second PCI, and transmit a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the downlink control information message.
[0023] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the downlink control information message indicates one or more of the first PCI or the second PCI via one or more cell indicator fields.
[0024] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the downlink control information message indicates the first PCI and the second PCI and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for selecting between the first PCI and the second PCI based on a RSRP threshold.
[0025] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the downlink control information message indicates the first PCI and the second PCI and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for selecting between the first PCI and the second PCI based on a first RSRP threshold associated with the first PCI and based on a second RSRP threshold associated with the second PCI.
[0026] A method for wireless communications by a UE is described. The method may include receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP, and transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0027] A UE for wireless communications is described. The UE may include one or more memories storing processor executable code, and one or more processors coupled with the one or more memories. The one or more processors may individually or collectively be operable to execute the code to cause the UE to receive a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receive a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP, and transmit a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0028] Another UE for wireless communications is described. The UE may include means for receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP, and means for transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0029] A non-transitory computer-readable medium storing code for wireless communications is described. The code may include instructions executable by one or more processors to receive a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP, receive a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP, and transmit a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0030] Some examples of the method, UEs, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for selecting between the first PCI or the second PCI, where the SSB may be selected from the first set of SSBs or the second set of S SBs based on the selection of the first PCI or the second PCI.
[0031] Some examples of the method, UEs, and non-transitory computer-readable medium described herein may further include operations, features, means, or instructions for selecting between a first superset of SSBs and a second superset of SSBs, where the first superset includes the first subset of SSBs and the third subset of SSBs, and where the second superset includes the second subset of SSBs and the fourth subset of SSBs and selecting between the first PCI or the second PCI based on the selection between the first superset and the second superset, where the SSB may be selected based on the selection of the first PCI or the second PCI.
[0032] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the random access preamble may be associated with a random access procedure triggered by downlink control message and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for selecting between the first PCI or the second PCI based on the downlink control message including an indication of the first PCI or the second PCI, selecting, based on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based on one or more RSRP thresholds, and selecting, based on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based on the one or more RSRP thresholds.
[0033] In some examples of the method, UEs, and non-transitory computer-readable medium described herein, the random access preamble may be associated with a random access procedure triggered by downlink control message and the method, apparatuses, and non-transitory computer-readable medium may include further operations, features, means, or instructions for selecting between the first PCI or the second PCI based on the downlink control message including an indication of the first PCI or the second PCI, selecting, based on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based on the downlink control message including an indication of the first subset or the second subset, and selecting, based on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based on the downlink control message including an indication of the third subset or the fourth subset.
[0034] Details of one or more implementations of the subject matter described in this disclosure are set forth in the accompanying drawings and the description below. Other features, aspects, and advantages will become apparent from the description, the drawings, and the claims. Note that the relative dimensions of the following figures may not be drawn to scale.BRIEF DESCRIPTION OF THE DRAWINGS
[0035] FIG. 1 shows an example of a wireless communications system that supports synchronization signal block (SSB) selection in accordance with one or more aspects of the present disclosure.
[0036] FIG. 2 shows an example of a wireless communications system that supports SSB selection in accordance with one or more aspects of the present disclosure.
[0037] FIG. 3 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0038] FIG. 4 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0039] FIG. 5 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0040] FIG. 6 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0041] FIG. 7 shows an example of a wireless communications system that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0042] FIG. 8 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0043] FIG. 9 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0044] FIG. 10 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0045] FIG. 11 shows an example of a process flow that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0046] FIGs. 12 and 13 show block diagrams of devices that support SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0047] FIG. 14 shows a block diagram of a communications manager that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0048] FIG. 15 shows a diagram of a system including a device that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.
[0049] FIGs. 16 through 18 show flowcharts illustrating methods that support SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure.DETAILED DESCRIPTION
[0050] In a wireless communications system, a user equipment (UE) may use a random access procedure to establish or re-establish a connection with a cell. As part of the random access procedure, the UE may transmit a random access preamble in a random access resource. The UE may determine the random access resource for transmitting the random access preamble based on an association between the random access resource and a synchronization signal block (SSB) that is selected by the UE using an SSB selection technique. However, conventional SSB selection techniques used by the UE may be insufficient or unsuitable for inter-cell scenarios in which the UE receives SSBs from transmission reception points (TRPs) (e.g., both uplink TRPs with reduced downlink capabilities and downlink TRPs) in cells with different physical cell identifiers (PCIs) .
[0051] A UE may implement the techniques described herein to select an SSB for a random access procedure performed in an inter-cell scenario. In some examples, the SSB selection technique used by the UE may be based on the type of inter-cell scenario.
[0052] In a first type of inter-cell scenario, referred to as Scenario 1, the UE 115 may use one or more of the SSB selection techniques referred to as Option 1, Option 2, Option 3, and Option 4. In Option 1, described with reference to FIG. 3, the UE 115 may select between serving cell SSBs and non-serving cell SSBs, then select an SSB from the selected SSBs. In Option 2, described with reference to FIG. 4, the UE 115 may select a non-serving cell PCI, select between the non-serving cell PCI and the serving cell PCI, then select an SSB from the selected PCI. In Option 3, described with reference to FIG. 5, the UE 115 may use PCI-specific RSRP thresholds to select the SSB. In Option 4, described with reference to FIG. 6, the UE 115 may select one or more PCIs as indicated by a control message, then select an SSB associated with the PCI (s) .
[0053] In a second type of inter-cell scenario, referred to as Scenario 2, the UE 115-a may use one or more of the SSB selection techniques referred to as Option 5, Option 6, Option 7, and Option 8. In Option 5, described with reference to FIG. 8, the UE 115 may select a PCI, select between the SSBs groups associated with that PCI, then select an SSB from the selected SSB group. In Option 6, described with reference to FIG. 9, the UE 115 may select between first SSB groups and second SSB groups, select a PCI, then select an SSB associated with the PCI. In Option 7, described with reference to FIG. 10, the UE 115 may select a PCI indicated by a downlink control message, then select an SSB from the SSB groups associated with the PCI. In Option 8, described with reference to FIG. 11, the UE 115 may select both a PCI and an SSB group indicated by a downlink control message, then select an SSB from the SSB group.
[0054] Among other benefits, use of the SSB selection techniques described herein may allow a UE to improve a random access procedure in an inter-cell scenario by enabling selection of suitable random access resources for transmission of a random access preamble.
[0055] Aspects of the disclosure are initially described in the context of wireless communications systems. Additional aspects of the disclosure are described with reference to process flows. Aspects of the disclosure are further illustrated by and described with reference to apparatus diagrams, system diagrams, and flowcharts that relate to SSB selection in an inter-cell wireless communications system.
[0056] FIG. 1 shows an example of a wireless communications system 100 that supports SSB selection in accordance with one or more aspects of the present disclosure. The wireless communications system 100 may include one or more devices, such as one or more network devices (e.g., network entities 105) , one or more UEs 115, and a core network 130. In some examples, the wireless communications system 100 may be a Long Term Evolution (LTE) network, an LTE-Advanced (LTE-A) network, an LTE-A Pro network, a New Radio (NR) network, or a network operating in accordance with other systems and radio technologies, including future systems and radio technologies not explicitly mentioned herein.
[0057] The network entities 105 may be dispersed throughout a geographic area to form the wireless communications system 100 and may include devices in different forms or having different capabilities. In various examples, a network entity 105 may be referred to as a network element, a mobility element, a radio access network (RAN) node, or network equipment, among other nomenclature. In some examples, network entities 105 and UEs 115 may wirelessly communicate via communication link (s) 125 (e.g., a radio frequency (RF) access link) . For example, a network entity 105 may support a coverage area 110 (e.g., a geographic coverage area) over which the UEs 115 and the network entity 105 may establish the communication link (s) 125. The coverage area 110 may be an example of a geographic area over which a network entity 105 and a UE 115 may support the communication of signals according to one or more radio access technologies (RATs) .
[0058] The UEs 115 may be dispersed throughout a coverage area 110 of the wireless communications system 100, and each UE 115 may be stationary, or mobile, or both at different times. The UEs 115 may be devices in different forms or having different capabilities. 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 in the wireless communications system 100 (e.g., other wireless communication devices, including UEs 115 or network entities 105) , as shown in FIG. 1.
[0059] As described herein, a node of the wireless communications 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, a node may be a UE 115. As another example, a 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 yet other aspects of this example, the first, second, and third nodes may be different relative to these examples. Similarly, reference to a UE 115, network entity 105, apparatus, device, computing system, or the like may include disclosure of the UE 115, network entity 105, apparatus, device, computing system, or the like being a node. For example, disclosure that a UE 115 is configured to receive information from a network entity 105 also discloses that a first node is configured to receive information from a second node.
[0060] In some examples, network entities 105 may communicate with a core network 130, or with one another, or both. For example, network entities 105 may communicate with the core network 130 via backhaul communication link (s) 120 (e.g., in accordance with an S1, N2, N3, or other interface protocol) . In some examples, network entities 105 may communicate with one another via backhaul communication link (s) 120 (e.g., in accordance with an X2, Xn, or other interface protocol) either directly (e.g., directly between network entities 105) or indirectly (e.g., via the core network 130) . In some examples, network entities 105 may communicate with one another via a midhaul communication link 162 (e.g., in accordance with a midhaul interface protocol) or a fronthaul communication link 168 (e.g., in accordance with a fronthaul interface protocol) , or any combination thereof. The backhaul communication link (s) 120, midhaul communication links 162, or fronthaul communication links 168 may be or include one or more wired links (e.g., an electrical link, an optical fiber link) or one or more wireless links (e.g., a radio link, a wireless optical link) , among other examples or various combinations thereof. A UE 115 may communicate with the core network 130 via a communication link 155.
[0061] One or more of the network entities 105 or network equipment described herein may include or may be referred to as a base station 140 (e.g., a base transceiver station, a radio base station, an NR base station, an access point, a radio transceiver, a NodeB, an eNodeB (eNB) , a next-generation NodeB or giga-NodeB (either of which may be referred to as a gNB) , a 5G NB, a next-generation eNB (ng-eNB) , a Home NodeB, a Home eNodeB, or other suitable terminology) . In some examples, a network entity 105 (e.g., a base station 140) may be implemented in an aggregated (e.g., monolithic, standalone) base station architecture, which may be configured to utilize a protocol stack that is physically or logically integrated within one network entity (e.g., a network entity 105 or a single RAN node, such as a base station 140) .
[0062] In some examples, a network entity 105 may be implemented in a disaggregated architecture (e.g., a disaggregated base station architecture, a disaggregated RAN architecture) , which may be configured to utilize a protocol stack that is physically or logically distributed among multiple network entities (e.g., network entities 105) , such as an integrated access and 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, a network entity 105 may include one or more of a central unit (CU) , such as a CU 160, a distributed unit (DU) , such as a DU 165, a radio unit (RU) , such as an RU 170, a RAN Intelligent Controller (RIC) , such as an 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) system, such as an SMO system 180, or any combination thereof. An 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 transmission reception point (TRP) . One or more components of the network entities 105 in a disaggregated RAN architecture may be co-located, or one or more components of the network entities 105 may be located in distributed locations (e.g., separate physical locations) . In some examples, one or more of the network entities 105 of a disaggregated RAN architecture may be implemented as virtual units (e.g., a virtual CU (VCU) , a virtual DU (VDU) , a virtual RU (VRU) ) .
[0063] The split of functionality between a CU 160, a DU 165, and an RU 170 is flexible and may support different functionalities depending on which functions (e.g., network layer functions, protocol layer functions, baseband functions, RF functions, or any combinations thereof) are performed at a CU 160, a DU 165, or an RU 170. For example, a functional split of a protocol stack may be employed between a CU 160 and a DU 165 such that the CU 160 may support one or more layers of the protocol stack and the DU 165 may support one or more different layers of the protocol stack. In some examples, the CU 160 may host upper protocol layer (e.g., layer 3 (L3) , layer 2 (L2) ) functionality and signaling (e.g., Radio Resource Control (RRC) , service data adaptation protocol (SDAP) , Packet Data Convergence Protocol (PDCP) ) . The CU 160 (e.g., one or more CUs) may be connected to a DU 165 (e.g., one or more DUs) or an RU 170 (e.g., one or more RUs) , or some combination thereof, and the DUs 165, RUs 170, or both 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) functionality 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 a DU 165 and an 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 multiple different cells (e.g., via one or multiple different RUs, such as an RU 170) . In some cases, a functional split between a CU 160 and a DU 165 or between a DU 165 and an RU 170 may be within a protocol layer (e.g., some functions for a protocol layer may be performed by one of a CU 160, a DU 165, or an RU 170, while other functions of the protocol layer are performed by a different one of the CU 160, the DU 165, or the RU 170) . A CU 160 may be functionally split further into CU control plane (CU-CP) and CU user plane (CU-UP) functions. A CU 160 may be connected to a DU 165 via a midhaul communication link 162 (e.g., F1, F1-c, F1-u) , and a DU 165 may be connected to an RU 170 via a fronthaul communication link 168 (e.g., open fronthaul (FH) interface) . In some examples, a midhaul communication link 162 or a fronthaul communication link 168 may be implemented in accordance with an interface (e.g., a channel) between layers of a protocol stack supported by respective network entities (e.g., one or more of the network entities 105) that are in communication via such communication links.
[0064] In some wireless communications systems (e.g., the wireless communications system 100) , infrastructure and spectral resources for radio access may support wireless backhaul link capabilities to supplement wired backhaul connections, providing an IAB network architecture (e.g., to a core network 130) . In some cases, in an IAB network, one or more of the network entities 105 (e.g., network entities 105 or IAB node (s) 104) may be partially controlled by each other. The IAB node (s) 104 may be referred to as a donor entity or an IAB donor. A DU 165 or an RU 170 may be partially controlled by a CU 160 associated with a network entity 105 or base station 140 (such as a donor network entity or a donor base station) . The one or more donor entities (e.g., IAB donors) may be in communication with one or more additional devices (e.g., IAB node (s) 104) via supported access and backhaul links (e.g., backhaul communication link (s) 120) . IAB node (s) 104 may include an IAB mobile termination (IAB-MT) controlled (e.g., scheduled) by one or more DUs (e.g., DUs 165) of a coupled IAB donor. An IAB-MT may be equipped with an independent set of antennas for relay of communications with UEs 115 or may share the same antennas (e.g., of an RU 170) of IAB node (s) 104 used for access via the DU 165 of the IAB node (s) 104 (e.g., referred to as virtual IAB-MT (vIAB-MT) ) . In some examples, the IAB node (s) 104 may include one or more DUs (e.g., DUs 165) that support communication links with additional entities (e.g., IAB node (s) 104, UEs 115) within the relay chain or configuration of the access network (e.g., downstream) . In such cases, one or more components of the disaggregated RAN architecture (e.g., the IAB node (s) 104 or components of the IAB node (s) 104) may be configured to operate according to the techniques described herein.
[0065] For instance, an access network (AN) or RAN may include communications between access nodes (e.g., an IAB donor) , IAB node (s) 104, and one or more UEs 115. The IAB donor may facilitate connection between the core network 130 and the AN (e.g., via a wired or wireless connection to the core network 130) . That is, an IAB donor may refer to a RAN node with a wired or wireless connection to the core network 130. The IAB donor may include one or more of a CU 160, a DU 165, and an RU 170, in which case the CU 160 may communicate with the core network 130 via an interface (e.g., a backhaul link) . The IAB donor and IAB node (s) 104 may communicate via an F1 interface according to a protocol that defines signaling messages (e.g., an F1 AP protocol) . Additionally, or alternatively, the CU 160 may communicate with the core network 130 via an interface, which may be an example of a portion of a backhaul link, and may communicate with other CUs (e.g., including a CU 160 associated with an alternative IAB donor) via an Xn-C interface, which may be an example of another portion of a backhaul link.
[0066] IAB node (s) 104 may refer to RAN nodes that provide IAB functionality (e.g., access for UEs 115, wireless self-backhauling capabilities) . A DU 165 may act as a distributed scheduling node towards child nodes associated with the IAB node (s) 104, and the IAB-MT may act as a scheduled node towards parent nodes associated with IAB node (s) 104. That is, an IAB donor may be referred to as a parent node in communication with one or more child nodes (e.g., an IAB donor may relay transmissions for UEs through other IAB node (s) 104) . Additionally, or alternatively, IAB node (s) 104 may also be referred to as parent nodes or child nodes to other IAB node (s) 104, depending on the relay chain or configuration of the AN. The IAB-MT entity of IAB node (s) 104 may provide a Uu interface for a child IAB node (e.g., the IAB node (s) 104) to receive signaling from a parent IAB node (e.g., the IAB node (s) 104) , and a DU interface (e.g., a DU 165) may provide a Uu interface for a parent IAB node to signal to a child IAB node or UE 115.
[0067] For example, IAB node (s) 104 may be referred to as parent nodes that support communications for child IAB nodes, or may be referred to as child IAB nodes associated with IAB donors, or both. An IAB donor may include a CU 160 with a wired or wireless connection (e.g., backhaul communication link (s) 120) to the core network 130 and may act as a parent node to IAB node (s) 104. For example, the DU 165 of an IAB donor may relay transmissions to UEs 115 through IAB node (s) 104, or may directly signal transmissions to a UE 115, or both. The CU 160 of the IAB donor may signal communication link establishment via an F1 interface to IAB node (s) 104, and the IAB node (s) 104 may schedule transmissions (e.g., transmissions to the UEs 115 relayed from the IAB donor) through one or more DUs (e.g., DUs 165) . That is, data may be relayed to and from IAB node (s) 104 via signaling via an NR Uu interface to MT of IAB node (s) 104 (e.g., other IAB node (s) ) . Communications with IAB node (s) 104 may be scheduled by a DU 165 of the IAB donor or of IAB node (s) 104.
[0068] In the case of the techniques described herein applied in the context of a disaggregated RAN architecture, one or more components of the disaggregated RAN architecture may be configured to support SSB selection in an inter-cell wireless communications system 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 disaggregated RAN architecture (e.g., components such as an IAB node, a DU 165, a CU 160, an RU 170, an RIC 175, an SMO system 180) .
[0069] A 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 terminology, where the “device” may also be referred to as a unit, a station, a terminal, or a client, among other examples. A 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, a UE 115 may include or be referred to as a wireless local loop (WLL) station, an Internet of Things (IoT) device, an Internet of Everything (IoE) device, or a machine type communications (MTC) device, among other examples, which may be implemented in various objects such as appliances, vehicles, or meters, among other examples.
[0070] The UEs 115 described herein may be able to communicate with various types of devices, such as UEs 115 that may sometimes operate as relays, as well as the network entities 105 and the network equipment including macro eNBs or gNBs, small cell eNBs or gNBs, or relay base stations, among other examples, as shown in FIG. 1.
[0071] The UEs 115 and the network entities 105 may wirelessly communicate with one another via the communication link (s) 125 (e.g., one or more access links) using resources associated with one or more carriers. The term “carrier” may refer to a set of RF spectrum resources having a defined PHY layer structure for supporting the communication link (s) 125. For example, a carrier used for the communication link (s) 125 may include a portion of an RF spectrum band (e.g., a bandwidth part (BWP) ) that is operated according to one or more PHY layer channels for a given RAT (e.g., LTE, LTE-A, LTE-A Pro, NR) . Each PHY layer channel may carry acquisition signaling (e.g., synchronization signals, system information) , control signaling that coordinates operation for the carrier, user data, or other signaling. The wireless communications system 100 may support communication with a UE 115 using carrier aggregation or multi-carrier operation. A UE 115 may be configured with multiple downlink component carriers and one or more uplink component carriers according to a carrier aggregation configuration. Carrier aggregation may be used with both frequency division duplexing (FDD) and time division duplexing (TDD) component carriers. Communication between a network entity 105 and other devices may refer to communication between the devices and any portion (e.g., entity, sub-entity) of a network entity 105. For example, the terms “transmitting, ” “receiving, ” or “communicating, ” when referring to a network entity 105, may refer to any portion of a network entity 105 (e.g., a base station 140, a CU 160, a DU 165, a RU 170) of a RAN communicating with another device (e.g., directly or via one or more other network entities, such as one or more of the network entities 105) .
[0072] Signal waveforms transmitted via a carrier may be made up of multiple subcarriers (e.g., using multi-carrier modulation (MCM) techniques such as orthogonal frequency division multiplexing (OFDM) or discrete Fourier transform spread OFDM (DFT-S-OFDM) ) . In a system employing MCM techniques, a resource element may refer to resources of one symbol period (e.g., a duration of one modulation symbol) and one subcarrier, in which case the symbol period and subcarrier spacing may be inversely related. The quantity 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) , such that a relatively higher quantity of resource elements (e.g., in a transmission duration) and a relatively higher order of a modulation scheme may correspond to a relatively higher rate of communication. A wireless communications resource may refer to a combination of an RF spectrum resource, a time resource, and a spatial resource (e.g., a spatial layer, a beam) , and the use of multiple spatial resources may increase the data rate or data integrity for communications with a UE 115.
[0073] The time intervals for the network entities 105 or the UEs 115 may be expressed in multiples of a basic time unit which may, for example, refer to a sampling period of Ts=1 / (Δfmax·Nf) seconds, for which Δfmax may represent a supported subcarrier spacing, and Nf may represent a supported discrete Fourier transform (DFT) size. Time intervals of a communications resource 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) .
[0074] Each frame may include multiple consecutively-numbered subframes or slots, and each subframe or slot may have the same duration. In some examples, a frame may be divided (e.g., in the time domain) into subframes, and each subframe may be further divided into a quantity of slots. Alternatively, each frame may include a variable quantity of slots, and the quantity of slots may depend on subcarrier spacing. Each slot may include a quantity of symbol periods (e.g., depending on the length of the cyclic prefix prepended to each symbol period) . In some wireless communications systems, such as the wireless communications system 100, a slot may further be divided into multiple mini-slots associated with one or more symbols. Excluding the cyclic prefix, each symbol period may be associated with one or more (e.g., Nf) sampling periods. The duration of a symbol period may depend on the subcarrier spacing or frequency band of operation.
[0075] A subframe, a slot, a mini-slot, or a symbol may be the smallest scheduling unit (e.g., in the time domain) of the wireless communications system 100 and may be referred to as a transmission time interval (TTI) . In some examples, the TTI duration (e.g., a quantity of symbol periods in a TTI) may be variable. Additionally, or alternatively, the smallest scheduling unit of the wireless communications system 100 may be dynamically selected (e.g., in bursts of shortened TTIs (sTTIs) ) .
[0076] Physical channels may be multiplexed for communication using a carrier according to various techniques. A physical control channel and a physical data channel may be multiplexed for signaling via a downlink carrier, for example, using one or more of time division multiplexing (TDM) techniques, frequency division multiplexing (FDM) techniques, or hybrid TDM-FDM techniques. A control region (e.g., a control resource set (CORESET) ) for a physical control channel may be defined by a set of symbol periods and may extend across the system bandwidth or a subset of the system bandwidth of the carrier. One or more control regions (e.g., CORESETs) may be configured for a set of the UEs 115. For example, one or more of the UEs 115 may monitor or search control regions for control information according to one or more search space sets, and each search space set may include one or multiple control channel candidates in one or more aggregation levels arranged in a cascaded manner. An aggregation level for a control channel candidate may refer to an amount of control channel resources (e.g., control channel elements (CCEs) ) associated with encoded information for a control information format having a given payload size. Search space sets may include common search space sets configured for sending control information to UEs 115 (e.g., one or more UEs) or may include UE-specific search space sets for sending control information to a UE 115 (e.g., a specific UE) .
[0077] A network entity 105 may provide communication coverage via one or more cells, for example a macro cell, a small cell, a hot spot, or other types of cells, or any combination thereof. The term “cell” may refer to a logical communication entity used for communication with a network entity 105 (e.g., using a carrier) and may be associated with an identifier for distinguishing neighboring cells (e.g., a PCI, a virtual cell identifier (VCID) ) . In some examples, a cell also may refer to a coverage area 110 or a portion of a coverage area 110 (e.g., a sector) over which the logical communication entity operates. Such cells may range from smaller areas (e.g., a structure, a subset of structure) to larger areas depending on various factors such as the capabilities of the network entity 105. For example, a cell may be or include a building, a subset of a building, or exterior spaces between or overlapping with coverage areas 110, among other examples.
[0078] A macro cell generally covers a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by the UEs 115 with service subscriptions with the network provider supporting the macro cell. A small cell may be associated with a network entity 105 operating with lower power (e.g., a base station 140 operating with lower power) relative to a macro cell, and a small cell may operate using the same or different (e.g., licensed, unlicensed) frequency bands as macro cells. Small cells may provide unrestricted access to the UEs 115 with service subscriptions with the network provider or may provide restricted access to the UEs 115 having an association with the small cell (e.g., the UEs 115 in a closed subscriber group (CSG) , the UEs 115 associated with users in a home or office) . A network entity 105 may support one or more cells and may also support communications via the one or more cells using one or multiple component carriers.
[0079] In some examples, a network entity 105 (e.g., a base station 140, an RU 170) may be movable and therefore provide communication coverage for a moving coverage area, such as the coverage area 110. In some examples, coverage areas 110 (e.g., different coverage areas) associated with different technologies may overlap, but the coverage areas 110 (e.g., different coverage areas) may be supported by the same network entity (e.g., a network entity 105) . In some other examples, overlapping coverage areas, such as a coverage area 110, associated with different technologies may be supported by different network entities (e.g., the network entities 105) . The wireless communications system 100 may include, for example, a heterogeneous network in which different types of the network entities 105 support communications for coverage areas 110 (e.g., different coverage areas) using the same or different RATs.
[0080] The wireless communications system 100 may be configured to support ultra-reliable communications or low-latency communications, or various combinations thereof. For example, the wireless communications system 100 may be configured to support ultra-reliable low-latency communications (URLLC) . The UEs 115 may be designed to support ultra-reliable, low-latency, or critical functions. Ultra-reliable communications 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.
[0081] In some examples, a UE 115 may be configured to support communicating directly with other UEs (e.g., one or more of the UEs 115) via a device-to-device (D2D) communication link, such as a D2D communication link 135 (e.g., in accordance with a peer-to-peer (P2P) , D2D, or sidelink protocol) . In some examples, one or more UEs 115 of a group that are performing D2D communications may be within the coverage area 110 of a network entity 105 (e.g., a base station 140, an RU 170) , which may support aspects of such D2D communications being configured by (e.g., scheduled by) the network entity 105. In some examples, one or more UEs 115 of such a group may be outside the coverage area 110 of a network entity 105 or may be otherwise unable to or not configured to receive transmissions from a network entity 105. In some examples, groups of the UEs 115 communicating via D2D communications may support a one-to-many (1: M) system in which each UE 115 transmits to one or more of the UEs 115 in the group. In some examples, a network entity 105 may facilitate the scheduling of resources for D2D communications. In some other examples, D2D communications may be carried out between the UEs 115 without an involvement of a network entity 105.
[0082] 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 5G core (5GC) , which may include at least one control plane entity that manages access and mobility (e.g., a mobility management entity (MME) , an access and mobility management function (AMF) ) and at least one user plane entity that routes packets or interconnects to external networks (e.g., a serving gateway (S-GW) , a Packet Data Network (PDN) gateway (P-GW) , or a user plane function (UPF) ) . The control plane entity may manage non-access stratum (NAS) functions such as mobility, authentication, and bearer management for the UEs 115 served by the network entities 105 (e.g., base stations 140) associated with the core network 130. User IP packets may be transferred through the user plane entity, which may provide IP address allocation as well as other functions. The user plane entity may be connected to IP services 150 for one or more network operators. The IP services 150 may include access to the Internet, Intranet (s) , an IP Multimedia Subsystem (IMS) , or a Packet-Switched Streaming Service.
[0083] The wireless communications system 100 may operate using one or more frequency bands, which may be in the range of 300 megahertz (MHz) to 300 gigahertz (GHz) . Generally, the region from 300 MHz to 3 GHz is known as the ultra-high frequency (UHF) region or decimeter band because the wavelengths range from approximately 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 the waves may penetrate structures sufficiently for a macro cell to provide service to the UEs 115 located indoors. Communications using UHF waves may be associated with smaller antennas and shorter ranges (e.g., less than one hundred kilometers) compared to communications using the smaller frequencies and longer waves of the high frequency (HF) or very high frequency (VHF) portion of the spectrum below 300 MHz.
[0084] The wireless communications system 100 may utilize both licensed and unlicensed RF spectrum bands. For example, the wireless communications system 100 may employ License Assisted Access (LAA) , LTE-Unlicensed (LTE-U) RAT, or NR technology using an unlicensed band such as the 5 GHz industrial, scientific, and medical (ISM) band. While operating using unlicensed RF spectrum bands, devices such as the network entities 105 and the UEs 115 may employ carrier sensing for collision detection and avoidance. In some examples, operations using unlicensed bands may be based on a carrier aggregation configuration in conjunction with component carriers operating using a licensed band (e.g., LAA) . Operations using unlicensed spectrum may include downlink transmissions, uplink transmissions, P2P transmissions, or D2D transmissions, among other examples.
[0085] A network entity 105 (e.g., a base station 140, an RU 170) or a UE 115 may be equipped with multiple antennas, which may be used to employ techniques such as transmit diversity, receive diversity, multiple-input multiple-output (MIMO) communications, or beamforming. The antennas of a network entity 105 or a UE 115 may be located within 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 a network entity 105 may be located at diverse geographic locations. A network entity 105 may include an antenna array with a set of rows and columns of antenna ports that the network entity 105 may use to support beamforming of communications with a UE 115. Likewise, a UE 115 may include one or more antenna arrays that may support various MIMO or beamforming operations. Additionally, or alternatively, an antenna panel may support RF beamforming for a signal transmitted via an antenna port.
[0086] The network entities 105 or the UEs 115 may use MIMO communications to exploit multipath signal propagation and increase spectral efficiency by transmitting or receiving multiple signals via different spatial layers. Such techniques may be referred to as spatial multiplexing. The multiple signals may, for example, be transmitted by the transmitting device via different antennas or different combinations of antennas. Likewise, the multiple signals may be received by the 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 used for channel measurement and reporting. MIMO techniques include single-user MIMO (SU-MIMO) , for which multiple spatial layers are transmitted to the same receiving device, and multiple-user MIMO (MU-MIMO) , for which multiple spatial layers are transmitted to multiple devices.
[0087] 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 steer 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 the signals communicated via antenna elements of an antenna array such that some signals propagating along particular orientations with respect to an antenna array experience constructive interference while others experience destructive interference. The adjustment of signals communicated via the antenna elements may include a transmitting device or a receiving device applying amplitude offsets, phase offsets, or both to signals carried via the antenna elements associated with the device. The adjustments associated with each of the antenna elements may be defined by a beamforming weight set associated with a particular orientation (e.g., with respect to the antenna array of the transmitting device or receiving device, or with respect to some other orientation) .
[0088] The wireless communications 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. An RLC layer may perform packet segmentation and reassembly to communicate via logical channels. A MAC layer may perform priority handling and multiplexing of logical channels into transport channels. The MAC layer also may implement error detection techniques, error correction techniques, or both to support retransmissions to improve link efficiency. In the control plane, an RRC layer may provide establishment, configuration, and maintenance of an RRC connection between a UE 115 and a network entity 105 or a core network 130 supporting radio bearers for user plane data. A PHY layer may map transport channels to physical channels.
[0089] In some cases, a UE 115 may be in an inter-cell scenario where one or more serving cells are configured and where each serving cell is associated with one or more non-serving cells. A UE 115 in an inter-cell scenario (e.g., Scenario 1, Scenario 2) may use the SSB selection techniques described herein to select an SSB for a random access procedure. An inter-cell scenario may also be referred to using other suitable terminology.
[0090] In the first type of inter-cell scenario, referred to as Scenario 1, the UE 115 may use one or more of the SSB selection techniques referred to as Option 1, Option 2, Option 3, and Option 4. In Option 1, described with reference to FIG. 3, the UE 115 may select between serving cell SSBs and non-serving cell SSBs (Step 1) , then select an SSB from the selected SSBs (Step 2) . In Option 2, described with reference to FIG. 4, the UE 115 may select a non-serving cell PCI (Step 1) , select between the non-serving cell PCI and the serving cell PCI (Step 2) , then select an SSB from the selected PCI (Step 3) . In Option 3, described with reference to FIG. 5, the UE 115 may use PCI-specific RSRP thresholds to select the SSB. In Option 4, described with reference to FIG. 6, the UE 115 may select one or more PCIs as indicated by a control message, then select an SSB associated with the PCI (s) .
[0091] In the second type of inter-cell scenario, referred to as Scenario 2, the UE 115-a may use one or more of the SSB selection techniques referred to as Option 5, Option 6, Option 7, and Option 8. In Option 5, described with reference to FIG. 8, the UE 115 may select a PCI (Step 1) , select between the SSBs groups associated with that PCI (Step 2) , then select an SSB from the selected SSB group. In Option 6, described with reference to FIG. 9, the UE 115 may select between first SSB groups and second SSB groups (Step 1) , select a PCI (Step 2) , then select an SSB associated with the PCI. In Option 7, described with reference to FIG. 10, the UE 115 may select a PCI indicated by a downlink control message, then select an SSB from the SSB groups associated with the PCI. In Option 8, described with reference to FIG. 11, the UE 115 may select both a PCI and an SSB group indicated by a downlink control message, then select an SSB from the SSB group.
[0092] Although described separately, aspects of the SSB selection techniques described herein may be combined.
[0093] FIG. 2 shows an example of a wireless communications system 200 that supports SSB selection in accordance with one or more aspects of the present disclosure. The wireless communications system 200 may be an example of the wireless communications system 100. The wireless communications system 200 may include a serving cell 205 for the UE 115-a and one or more non-serving cells 210 (e.g., non-serving cell 210-a, non-serving cell 210-b) . Each cell may be associated with a respective PCI that is different from the other PCIs. The wireless communications system 200 may be an example of a first type of inter-cell scenario referred to as Scenario 1.
[0094] In Scenario 1, the downlink TRP 220 may belong to the serving cell 205 whereas the uplink TRPs 215 may belong to the non-serving cells 210. Thus, in Scenario 1, SSBs transmitted by the downlink TRP 220 may be associated with the PCI (e.g., PCI A) of the serving cell 205, whereas SSBs transmitted by the uplink TRPs 215 (e.g., TRP 215-a-1, TRP 215-a-2, TRP 215-b-1, TRP 215-b-2) may be associated with the PCIs (e.g., PCI B, PCI C) of the non-serving cells 210. The PCI of the serving cell 205 may be referred to as the serving cell PCI and the PCI of a non-serving cell may be referred to as the non-serving cell PCI or as an “additional” PCI.
[0095] For the purposes of the present disclosure, the term “multi-cell” may refer to scenarios where multiple serving cells 205 are configured. Comparatively, the term “inter-cell” may be used to refer to scenarios where one or more serving cells 205 are configured, while each serving cell 205 is associated with one or more non-serving cells 210.
[0096] A downlink TRP 220 may communicate both data and control signals in the downlink and uplink directions, whereas an uplink TRP 215 may receive data in the uplink direction and transmit limited control signals (e.g., reference signals, SSBs) in the downlink. Further, the uplink TRPs 215 may have reduced / limited transmission power relative to the downlink TRPs 220. Thus, the uplink TRPs 215 may have more reduced downlink capabilities than the downlink TRPs 220. In some examples, a downlink TRP 220 may be a network entity 105, a macro node, or a central node. The uplink TRPs 215 may be connected to the downlink TRP 220 via backhaul. The uplink TRPs 215 may provide coverage extension relative to other inter-cell scenarios. Since the downlink control or data may be transmitted from the downlink TRPs 220 which are different from the uplink TRPs 215, and there may be more uplink TRPs 215 than downlink TRPs 220, the inter-cell scenario may be referred to as an asymmetric inter-cell scenario.
[0097] SSBs for a random access procedure may be transmitted by the TRPs in the wireless communication system 200. For example, uplink TRP 215-a-2 may transmit SSBs 225-a, uplink TRP 215-b-2 may transmit SSBs 225-b, and downlink TRP 220 may transmit SSBs 225-c. Although shown with SSBs transmitted by a subset of the TRPs, SSBs may be transmitted by any quantity of the TRPs. Although shown with two non-serving cells 210, Scenario 1 may involve any quantity of non-serving cells 210.
[0098] As part of the random access procedure, the UE 115-a may select an SSB from the SSBs 225 transmitted by the TRPs, determine a random access (e.g., physical random access channel (PRACH) ) resource associated with the SSB, and transmit a random access preamble in the random access resource. In a contention-free random access (CFRA) procedure in which random access resources associated with SSBs are provided to the UE 115-a (e.g., via a rach-ConfigDedicated message) , the UE 115-a may select one of the associated SSBs that has an RSRP above a threshold (e.g., rsrp-ThresholdSSB) (providing such an SSB exists) . In a contention-based random access (CBRA) procedure, the UE 115-a may select an SSB that has an RSRP above a threshold (e.g., rsrp-ThresholdSSB) (providing such an SSB exists) , otherwise the UE 115-a may select a random SSB. In either type of random access procedure, the UE may set the index of the preamble to the index (e.g., ra-PreambleIndex) corresponding to the selected SSB.
[0099] However, conventional SSB selection techniques may be insufficient or unsuitable for inter-cell scenarios in which the UE 115-a receives SSBs from both downlink TRPs 220 and uplink TRPs 215 associated with different cells with different PCIs. Accordingly, the UE 115-a may use the SSB selection techniques described herein to select the SSB in inter-cell scenarios. In some examples, aspects of the SSB selection techniques (e.g., Option 1, Option 2, Option 3, Option 4) described with reference to FIGs. 3–6 may be used for Scenario 1, and aspects of the SSB selection techniques (e.g., Option 5, Option 6, Option 7, Option 8) described with reference to FIGs. 8–11 may be used for a second inter-cell scenario, illustrated in FIG. 7, that is referred to as Scenario 2.
[0100] Option 1, Option 2, and Option 3 may be applied to CFRA indicated by the UE 115-a or CBRA that is initiated by the UE 115-a or the network. Option 4 may be applied to physical downlink control channel (PDCCH) ordered CBRA or CFRA. Given that the uplink TRPs 215 in Scenario 1 are associated with different PCIs than the serving cell 205, Option 1, Option 2, Option 3, and Option 4 may not be applied for initial access. For initial access, the UE 115-a may transmit PRACH to the serving cell 205 and select the associated SSB using one or more RSRP threshold (s) configured via RRC.
[0101] However, in some examples (e.g., where the UE 115-a is close to an uplink TRP 215 in a neighbor cell) , the UE 115-a may perform initial access to the uplink TRP of the neighbor cell. In this case, the UE 115-a may be configured with multiple SSB groups in a system information message (e.g., SIB1) where each SSB group is associated with a PCI (serving cell PCI or non-serving cell PCI) . For SSB configuration in each SSB group, the SSB transmit power, SSB periodicity, time and frequency location of SSBs may be configured. In addition, for each non-serving cell PCI, the corresponding PRACH configuration may be configured via SIB1. Further, the RSRP threshold (s) in Options 1–4 may be configured via SIB1.
[0102] FIG. 3 shows an example of a process flow 300 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 300 may be implemented by a UE such as the UE 115-a and may be described with reference to FIG. 2. The UE 115-a may implement aspects of the process flow 300 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1. The process flow 300 may be an example of a first option (Option 1) for selecting an SSB in Scenario 1. Thus, the process flow 300 may be implemented by the UE 115-a if the UE 115-a is configured with multiple SSB groups, where each SSB group is associated with a respective cell and the PCI of that cell.
[0103] At signaling operation 305, the UE 115-a may receive SSBs associated with different cells. For example, the UE 115-a may receive (e.g., from downlink TRP 220) SSBs associated with the serving cell 205 and PCI C. And the UE 115-a may receive (e.g., from uplink TRP 215-a-2, from uplink TRP 215-b-2) SSBs associated with one or more of the non-serving cells 210 and the PCIs of those non-serving cells (e.g., PCI A, PCI B) .
[0104] At processing operation 310, the UE 115-a may select an SSB group by selecting between a first SSB group that includes the SSBs associated with the serving cell 205 and a second SSB group that includes the SSBs associated with the non-serving cells 210 (e.g., both non-serving cell 210-a and non-serving cell 210-b) . In some examples, the operations at processing operation 310 may be referred to as Step 1 of Option 1.
[0105] The UE 115-a may implement one of several options for selecting the SSB group. For example, the UE 115-a may implement Option 1–1, with processing operations 310-a, Option 1-2, with processing operations 310-b, or Option 1–3, with processing operations 310-c.
[0106] In Option 1–1, the UE 115-a may be configured with (e.g., via SIB1 or RRC) and use a single RSRP threshold (e.g., rsrp-ThresholdSSB-PCI) as a basis for selecting the SSB group. The UE 115-a may compare the RSRP threshold with one or more RSRP metrics and select a group of SSBs (e.g., the first group associated with the serving cell 205 or the second group associated with the non-serving cells 210) based on the comparison (s) .
[0107] In a first alternative for Option 1–1, which may prioritize the serving cell 205-a, the UE 115-a may select the first SSB group associated with the serving cell 205 unless the RSRP metric associated with the first SSB group is less than the RSRP threshold. That is, the UE 115-a may select the first SSB group if the RSRP metric associated with the first SSB group is greater than or equal to the RSRP threshold, which may indicate that the UE 115-a is in the coverage area of the serving cell 205. In the first alternative for Option 1–1, the RSRP metric may be an average RSRP for the first SSB group, a weighted RSRP for the first SSB group, the highest RSRP for the first SSB group, or the lowest RSRP for the first SSB group, among other options. In the first alternative for Option 1–1, the RSRP metric may be determined by measuring the SSBs in the first SSB group.
[0108] In a second alternative for Option 1–1, which may prioritize the non-serving cells 210, the UE 115-a may select the second SSB group associated with the non-serving cell 210 unless the RSRP metric associated with the second SSB group is less than the RSRP threshold. In the second alternative for Option 1–1, the RSRP metric may be an average RSRP for the second SSB group, a weighted RSRP for the second SSB group, the highest RSRP for the second SSB group, or the lowest RSRP for the second SSB group, among other options. Alternatively, in the second alternative for Option 1–1 the RSRP metric may be an average RSRP for the second SSB group associated with a selected PCI, a weighted RSRP for the second SSB group associated with a selected PCI, the highest RSRP for the second SSB group associated with a selected PCI, or the lowest RSRP for the second SSB group associated with a selected PCI. The selected PCI may have the lowest PCI value, may be associated with the highest SSB RSRP, or may be randomly selected. In the second alternative for Option 1–1, the RSRP metric may be determined by measuring at least some of the SSBs in the second SSB group.
[0109] In a third alternative for Option 1–1, the UE 115-a select the first SSB group associated with the serving cell 205 unless the RSRP metric of both SSB groups is less than the RSRP threshold. In the third alternative for Option 1–1, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the SSBs associated with both groups (e.g., the SSBs associated with each PCI) , among other options. In the third alternative for Option 1–1, the RSRP metric may be determined by measuring the SSBs in both the first and second SSB groups.
[0110] In Option 1–2, the UE 115-a may be configured with (e.g., via SIB1 or RRC) and use multiple RSRP thresholds as bases for selecting the SSB group. The RSRP thresholds may be SSB group-specific. For example, the UE 115-a may be configured with a first RSRP threshold (e.g., rsrp-ThresholdSSB-servingPCI) for the first SSB group associated with the serving cell 205, and may be configured with a second RSRP threshold (e.g., rsrp-ThresholdSSB-non-servingPCI) for the second SSB group associated with the non-serving cells 210. The RSRP thresholds may be configured via a control message such as an RRC message or a system information (e.g., SIB1) message. The UE 115-a may compare one or more of the RSRP threshold (s) with one or more RSRP metrics and select a group of SSBs (e.g., the first group associated with the serving cell 205 or the second group associated with the non-serving cells 210) based on the comparison (s) . In Option 1–2, the RSRP metric (s) may be determined by measuring SSBs in the first SSB group, in the second SSB group, or both.
[0111] In Option 1–2, the UE 115-a may randomly select an SSB group from the first SSB group and the second SSB group if both of the respective RSRP metrics associated with the SSB groups satisfy (e.g., are greater than or equal to) their respective RSRP thresholds, or if neither of the respective RSRP metrics associated with the SSB groups satisfy their respective thresholds. For example, if a first RSRP metric associated with the first (e.g., serving cell) SSB group satisfies (e.g., is no less than) the first RSRP threshold, and if a second RSRP metric associated with the second (e.g., non-serving cell) SSB group satisfies (e.g., is no less than) the second RSRP threshold, the UE 115-a may randomly select an SSB group from the first SSB group and the second SSB group. Similarly, if the first RSRP metric associated with the first (e.g., serving cell) SSB group does not satisfy (e.g., is less than) the first RSRP threshold, and if the second RSRP metric associated with the second (e.g., non-serving cell) SSB group does not satisfy (e.g., is less than) the second RSRP threshold, the UE 115-a may randomly select an SSB group from the first SSB group and the second SSB group.
[0112] On the other hand, in Option 1–2, if only one SSB group has an RSRP metric that satisfies the respective RSRP threshold for that SSB group, the UE 115-a may select that SSB group. For example, if the first RSRP metric associated with the first SSB group satisfies (e.g., is greater or equal to, is no less than) the first RSRP threshold for the first SSB group, the UE 115-a may select the first SSB group. If the second RSRP metric associated with the second SSB group satisfies (e.g., is greater or equal to, is no less than) the second RSRP threshold for the second SSB group, the UE 115-a may select the second SSB group.
[0113] In Option 1–2, the first RSRP metric may be an average RSRP for the first SSB group, a weighted RSRP for the first SSB group, the highest RSRP for the first SSB group, or the lowest RSRP for the first SSB group, among other options. In Option 1–2, the first RSRP metric may be determined by measuring the SSBs in the first SSB group. In Option 1–2, the second RSRP metric may be an average RSRP for the second SSB group, a weighted RSRP for the second SSB group, the highest RSRP for the second SSB group, or the lowest RSRP for the second SSB group, among other options. Alternatively, in Option 1–2 the second RSRP metric may be an average RSRP for a selected PCI of the second SSB group, a weighted RSRP for the selected PCI of the second SSB group, the highest RSRP for the selected PCI of the second SSB group, or the lowest RSRP for the selected PCI of the second SSB group. The selected PCI may have the lowest PCI value, may be associated with the highest SSB RSRP, or may be randomly selected. In Option 1–2, the RSRP metric may be determined by measuring at least some of the SSBs in the second SSB group.
[0114] In Option 1–3, which may be implemented for a PDCCH ordered PRACH, the UE 115-a may select between the first SSB group and the second SSB group based on an indication in the downlink control information (DCI) associated with the PDCCH ordered PRACH. For example, one or more bits in the DCI may indicate whether the UE 115-a is to select the first SSB group or the second SSB group.
[0115] Thus, after processing operation 310, the UE 115-a may have selected either the first SSB group (associated with the serving cell 205 and PCI C) or the second SSB group (associated with one or more non-serving cells 210 and their respective PCIs) .
[0116] At processing operation 315, the UE 115-a may select an SSB from the selected SSB group. In some examples, processing operation 315 may be referred to as Step 2 of Option 1. If the selected SSB group is the first SSB group, the UE 115-a may select the SSB using the SSB selection technique described with reference to FIG. 1. If the selected SSB group is the second SSB group, the UE 115-a may first select a PCI (e.g., PCI A or PCI B) from the PCIs associated with the second SSB group, then select an SSB from the SSBs associated with the selected PCI using the SSB selection technique described with reference to FIG. 1. To select the PCI, the UE 115-a may determine, for each PCI, a respective RSRP metric for the SSBs associated with that PCI. The UE 115-a may then select the PCI associated with the SSBs that have highest RSRP metric. Alternatively, the UE 115-a may select the PCI randomly.
[0117] At signaling operation 320, the UE 115-a may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-a.
[0118] Thus, the UE 115-a may implement aspects of Option 1 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1.
[0119] FIG. 4 shows an example of a process flow 400 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 400 may be implemented by a UE such as the UE 115-a and may be described with reference to FIG. 2. The UE 115-a may implement aspects of the process flow 400 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1. The process flow 400 may be an example of a second option (Option 2) for selecting an SSB in Scenario 1.
[0120] At signaling operation 405, the UE 115-a may receive SSBs associated with different cells. For example, the UE 115-a may receive (e.g., from downlink TRP 220) SSBs associated with the serving cell 205 and PCI C. And the UE 115-a may receive (e.g., from uplink TRP 215-a-2, from uplink TRP 215-b-2) SSBs associated with one or more of the non-serving cells 210 and the PCIs of those non-serving cells 210 (e.g., PCI A, PCI B) .
[0121] At processing operation 410, the UE 115-a may select a PCI from the PCIs of the non-serving cells 210. For example, the UE 115-a may select PCI A associated with the non-serving cell 210-a or the UE 115-a may select PCI B associated with the non-serving cell 210-b. Put another way, from the second group of SSBs associated with the non-serving cells 210, the UE 115-a may select the sub-group of SSBs associated with one of the non-serving cells 210. To select the non-serving cell PCI, the UE 115-a may determine, for each non-serving cell PCI, a respective RSRP metric for the SSBs associated with that PCI. The UE 115-a may then select the non-serving cell PCI associated with the SSBs that have highest RSRP metric. Alternatively, the UE 115-a may select the non-serving cell PCI randomly. In some examples, the processing operation 410 may be referred to as Step 1 of Option 2.
[0122] At processing operation 415, the UE 115-a may select between the PCI of the serving cell 205 (e.g., PCI C) and the selected non-serving cell PCI (e.g., PCI A or PCI B) . In some examples, the processing operation 415 may be referred to as Step 2 of Option 2.
[0123] The UE 115-a may implement one of several options for selecting the PCI. For example, the UE 115-a may implement Option 2–1, with processing operations 415-a, or Option 2–2, with processing operations 415-b.
[0124] In Option 2–1, the UE 115-a may be configured with (e.g., via SIB1 or RRC) and use a single RSRP threshold (e.g., rsrp-ThresholdSSB-PCI) as a basis for selecting the PCI. The UE 115-a may compare the RSRP threshold with one or more RSRP metrics and select the PCI based on the comparison (s) . In a first alternative for Option 2–1, which may prioritize the serving cell 205, the UE 115-a may select the PCI of the serving cell 205 unless the RSRP metric associated with that PCI does not satisfy (e.g., is less than) the RSRP threshold. In the first alternative for Option 2–1, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the first SSB group associated with the serving cell 205, among other options. In the first alternative for Option 2–1, the RSRP metric may be determined by measuring the SSBs in the first SSB group associated with the serving cell 205.
[0125] In a second alternative for Option 2–1, which may prioritize the non-serving cell 210, the UE 115-a may select the PCI of the non-serving cell 210 unless the RSRP metric associated with that PCI does not satisfy (e.g., is less than) the RSRP threshold. In the second alternative for Option 2–1, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the SSB sub-group associated with the selected non-serving cell 210, among other options. In the second alternative for Option 2–1, the RSRP metric may be determined by measuring the SSBs in the SSB sub-group associated with the selected non-serving cell 210.
[0126] In a third alternative for Option 2–1, the UE 115-a may consider a collective RSRP metric for the SSBs associated with the serving cell 205 and the SSBs associated with the selected non-serving cell 210. In this alternative, the UE 115-a may select the PCI of the serving cell 205 unless the collective RSRP metric for the SSBs is less than the RSRP threshold. In the third alternative for Option 2–1, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the SSBs associated with the serving cell 205 and the selected non-serving cell 210, among other options. In the third alternative for Option 2–1, the RSRP metric may be determined by measuring the SSBs in the first SSB group associated with the serving cell 205 and the SSBs in the SSB sub-group associated with the selected non-serving cell 210.
[0127] In Option 2–2, the UE 115-a may be configured with (e.g., via SIB1 or RRC) and use multiple RSRP thresholds as bases for selecting the SSB group. The RSRP thresholds may be SSB group-specific. For example, the UE 115-a may determine a first RSRP threshold (e.g., rsrp-ThresholdSSB-servingPCI) for the first SSB group associated with the serving cell 205, and may determine a second RSRP threshold (e.g., rsrp-ThresholdSSB-non-servingPCI) for the SSB sub-group associated with the selected non-serving cell 210. The RSRP thresholds may be configured via a control message such as an RRC message or a system information (e.g., SIB1) message. The UE 115-a may compare one or more of the RSRP threshold (s) with one or more RSRP metrics and select a group of SSBs (e.g., the first SSB group associated with the serving cell 205 or the SSB sub-group associated with the selected non-serving cell 210) based on the comparison (s) . In Option 2–2, the RSRP metric (s) may be determined by measuring SSBs in the first SSB group, in the SSB sub-group, or both.
[0128] In Option 2–2, the UE 115-a may randomly select an SSB group from the first SSB group and the SSB sub-group if both of the respective RSRP metrics associated with the PCIs satisfy (e.g., are greater than or equal to) their respective RSRP thresholds, or if neither of the respective RSRP metrics associated with the PCIs satisfy their respective thresholds. For example, if a first RSRP metric associated with the first (e.g., serving cell) SSB group satisfies (e.g., is no less than) the first RSRP threshold, and if a second RSRP metric associated with the selected non-serving cell SSB sub-group satisfies (e.g., is no less than) the second RSRP threshold, the UE 115-a may randomly select an SSB group from the first SSB group and the SSB sub-group. Similarly, if the first RSRP metric associated with the first (e.g., serving cell) SSB group does not satisfy (e.g., is less than) the first RSRP threshold, and if the second RSRP metric associated with the selected non-serving cell SSB sub-group does not satisfy (e.g., is less than) the second RSRP threshold, the UE 115-a may randomly select an SSB group from the first SSB group and the SSB sub-group.
[0129] On the other hand, in Option 2–2, if only one SSB group has an RSRP metric that satisfies the respective RSRP threshold for that SSB group, the UE 115-a may select that SSB group. For example, if the first RSRP metric associated with the first SSB group satisfies (e.g., is greater or equal to, is no less than) the first RSRP threshold for the first SSB group, the UE 115-a may select the first SSB group. If the second RSRP metric associated with the SSB sub-group satisfies (e.g., is greater or equal to, is no less than) the second RSRP threshold for the SSB sub-group, the UE 115-a may select the SSB sub-group.
[0130] In Option 2–2, the first RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the first SSB group, among other options. In Option 2–2, the first RSRP metric may be determined by measuring the SSBs in the first SSB group. In Option 2–2, the second RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP for the SSB sub-group, among other options. In Option 1–2, the RSRP metric may be determined by measuring at least some of the SSBs in the SSB sub-group.
[0131] In some examples, the SSB group selection technique of Option 2–2 can be extended to an intra-cell scenario where both SSB groups (e.g., one SSB group for the downlink TRP and one SSB group for the uplink TRP) are associated with the serving cell PCI. Thus, Option 2–2 may be used to selected between SSB groups associated with the serving cell PCI.
[0132] Thus, after processing operation 415, the UE 115-a may have selected either the first SSB group (associated with the serving cell 205 and PCI C) or the SSB sub-group (associated with the selected non-serving cell 210 and its respective PCI) .
[0133] At processing operation 420, the UE 115-a may select an SSB from the selected SSB group. In some examples, the processing operation 420 may be referred to as Step 3 of Option 2. The UE 115-a may select the SSB using the SSB selection technique described with reference to FIG. 1. At signaling operation 425, the UE 115-a may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-a.
[0134] Thus, the UE 115-a may implement aspects of Option 2 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1.
[0135] FIG. 5 shows an example of a process flow 500 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 500 may be implemented by a UE such as the UE 115-a and may be described with reference to FIG. 2. The UE 115-a may implement aspects of the process flow 500 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1. The process flow 500 may be an example of a third option (Option 3) for selecting an SSB in Scenario 1.
[0136] At signaling operation 505, the UE 115-a may receive SSBs associated with different cells. For example, the UE 115-a may receive (e.g., from downlink TRP 220) SSBs associated with the serving cell 205 and PCI C. And the UE 115-a may receive (e.g., from uplink TRP 215-a-2, from uplink TRP 215-b-2) SSBs associated with one or more of the non-serving cells 210 and the PCIs of those non-serving cells 210 (e.g., PCI A, PCI B) .
[0137] At processing operation 510, the UE 115-a may be configured with (e.g., via SIB1 or RRC) with respective RSRP threshold for the PCIs (e.g., the UE 115-a may determine PCI-specific RSRP thresholds) . For example, the UE 115-a may determine a first RSRP threshold for the PCI of serving cell 205 (e.g., PCI C) , a second RSRP threshold for the PCI of the non-serving cell 210-a (e.g., PCI A) , and a third RSRP threshold for the PCI of the non-serving cell 210-b (e.g., PCI B) . The RSRP thresholds may be configured via a control message such as an RRC message or a system information (e.g., SIB1) message.
[0138] At processing operation 515, the UE 115-a may compare one or more of the RSRP threshold (s) with one or more RSRP metrics so that the UE 115-a can select, at processing operation 520, a PCI (and thus a group of SSBs) based on the comparison (s) . In Option 3, the RSRP metrics may be SSB-specific RSRP metrics.
[0139] In a first option, Option 3–1, the UE 115-a may determine if at least one of the SSBs associated with the serving cell PCI (e.g., PCI C) has an RSRP metric that satisfies (e.g., is equal to or greater than) the first RSRP threshold associated with the serving cell PCI. If so, the UE 115-a may select one of the serving cell SSBs whose RSRP metric satisfies the first RSRP threshold. If none of the SSBs associated with the serving cell PCI has an RSRP metric that satisfies the first RSRP threshold, the UE 115-a may determine if at least one of the SSBs associated with the non-serving cell PCIs has an RSRP metric that satisfies the RSRP threshold corresponding to that non-serving cell PCI. If so, the UE 115-a may select one of the non-serving cell SSBs whose RSRP metric satisfies the RSRP threshold for the PCI of that non-serving cell 210.
[0140] If none of the SSBs associated with the non-serving cell PCIs has an RSRP metric that satisfies the corresponding RSRP threshold for that PCI, the UE 115-a may implement one or more alternatives for selecting the SSB. In a first alternative (Alternative 1) , the UE 115-a may randomly select the SSB from all the received SSBs. In a second alternative (Alternative 2) , the UE 115-a may randomly select the SSB from the SSBs associated with the serving cell PCI. In a third alternative (Alternative 3) , the UE 115-a may randomly select the SSB from the SSBs associated with the non-serving cell PCI (s) .
[0141] In a second option, Option 3–2, the UE 115-a may determine if at least one of the received SSBs (for any PCI) has an RSRP metric that satisfies (e.g., is equal to or greater than) the RSRP threshold for the PCI associated with that SSB. If so, the UE 115-a may select one of SSBs whose RSRP metric satisfies the RSRP threshold for the PCI associated with that SSB. If none of received SSBs (for any PCI) has an RSRP metric that satisfies (e.g., is equal to or greater than) the RSRP threshold for the PCI associated with that SSB, the UE 115-a may implement one or more alternatives for selecting the SSB. For example, the UE 115-a may implement one of Alternative 1, Alternative 2, or Alternative 3 as described with reference to Option 3–1.
[0142] At signaling operation 525, after selecting the SSB, the UE 115-a may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-a.
[0143] Thus, the UE 115-a may implement aspects of Option 3 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1.
[0144] FIG. 6 shows an example of a process flow 600 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 600 may be implemented by a UE such as the UE 115-a and may be described with reference to FIG. 2. The UE 115-a may implement aspects of the process flow 600 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1. The process flow 600 may be an example of a fourth option (Option 4) for selecting an SSB in Scenario 1.
[0145] At signaling operation 605, the UE 115-a may receive SSBs associated with different cells. For example, the UE 115-a may receive (e.g., from downlink TRP 220) SSBs associated with the serving cell 205 and PCI C. And the UE 115-a may receive (e.g., from uplink TRP 215-a-2, from uplink TRP 215-b-2) SSBs associated with one or more of the non-serving cells 210 and the PCIs of those non-serving cells 210 (e.g., PCI A, PCI B) .
[0146] At processing operation 610, the UE 115-a may select one or more PCI (s) based on the PCI (s) being indicated by a downlink control message (e.g., a DCI message) , which may trigger the random access procedure associated with the SSBs. For example, the SSBs may be part of a PDCCH-ordered random access procedure. The PCI (s) may be indicated by one or more bits in the PDCCH associated with the DCI. For example, the one or more bits may indicate one or more of the PCI indices.
[0147] At processing operation 615, the UE 115-a may select an SSB associated with the PCI (s) selected at 610. If a single PCI is indicated by the DCI, the UE 115-a may select the SSB using the SSB selection technique described with reference to FIG. 2. If multiple PCIs are indicated by the DCI, the UE 115-a may select the SSB using aspects of the SSB selection techniques described with reference to Option 1, Option 2, or Option 3.
[0148] At signaling operation 620, after selecting the SSB, the UE 115-a may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-a.
[0149] Thus, the UE 115-a may implement aspects of Option 4 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 1.
[0150] FIG. 7 shows an example of a wireless communications system 700 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The wireless communications system 700 may be an example of the wireless communications system 100. The wireless communications system 700 may include a serving cell 705 for the UE 115-b and one or more non-serving cells 710 (e.g., non-serving cell 710-a, non-serving cell 710-b) . Each cell may be associated with a respective PCI that is different from the other PCIs. The wireless communications system 700 may be an example of the second type of inter-cell scenario referred to as Scenario 2.
[0151] In Scenario 2, each cell may have one or more downlink TRPs 720 and one or more uplink TRPs 715, each of which may transmit SSBs. For example, the serving cell 705 may include downlink TRP 720-c, uplink TRP 715-c-1, and uplink TRP 715-c-2, each of which may transmit SSBs associated with PCI C. Similarly, the non-serving cell 710-a may include downlink TRP 720-a, uplink TRP 715-a-1, and uplink TRP 715-a-2, each of which may transmit SSBs associated with PCI A. And the non-serving cell 710-b may include downlink TRP 720-b, uplink TRP 715-b-1, and uplink TRP 715-b-2, each of which may transmit SSBs associated with PCI B. For a given cell, the SSBs associated with the cell may be divided into a first group of SSBs that are transmitted by the downlink TRP 720 and a second group of SSBs that are transmitted by the one or more uplink TRPs 715. For example, the serving cell 705 may have a first group of SSBs (e.g., SSBs 725-a) transmitted from the downlink TRP 720-c and may have a second group of SSBs (e.g., SSBs 725-b) that are transmitted from the UL TRP 715-c-2. Thus, each cell may have an associated first group of SSBs and an associated second group of SSBs. Although shown with two non-serving cells 710, Scenario 2 may involve any quantity of non-serving cells 710.
[0152] In Scenario 2, the SSB selection techniques described with reference to FIG. 2 may be insufficient or unsuitable. Accordingly, the UE 115-b may use the SSB selection techniques described herein to select an SSB for a random access procedure that is initiated while the UE 115-b is in Scenario 2. For example, the UE 115-b may select an SSB by implementing aspects of Option 5, Option 6, Option 7, or Option 8 as described herein.
[0153] Option 5 and Option 6 may be applied to CFRA initiated by the UE 115-b or CBRA that is initiated by the UE 115-b or the network. Option 7 and Option 8 may be applied to PDCCH ordered CBRA or CFRA. For initial access, the UE 115-b may perform initial access to the serving cell 705. Therefore, for initial access, the UE 115-b may select an SSB from the two SSB groups associated with the serving cell 705. In this case, the non-serving cell PCI (s) and corresponding SSB groups may be configured via RRC signaling. Further, the RSRP threshold (s) in Options 5–8 may be configured via RRC signaling.
[0154] If the UE 115-b is close to the downlink TRP 720 or the uplink TRP 715 of a neighbor cell, the UE 115-b may perform initial access to the neighbor cell. In this case, the UE 115-b may be configured with one or more non-serving cell PCIs, where for each non-serving cell PCI, two SSB groups can be configured. In this case, the non-serving cell PCI (s) and SSB groups related to each non-serving cell PCI may be configured in a system information message (e.g., SIB1) . For each non-serving cell PCI, the corresponding PRACH configuration may be also configured via a system information message (e.g., SIB1) . Further, the RSRP threshold (s) in proposal 2 should also be configured via a system information message (e.g., SIB1) .
[0155] FIG. 8 shows an example of a process flow 800 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 800 may be implemented by a UE such as the UE 115-b and may be described with reference to FIG. 7. The UE 115-b may implement aspects of the process flow 800 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2. The process flow 800 may be an example of a first option (Option 5) for selecting an SSB in Scenario 2. Thus, the process flow 800 may be implemented by the UE 115-b if the UE 115-b is configured with multiple SSB groups per cell.
[0156] At signaling operation 805, the UE 115-b may receive SSBs associated with different cells. For example, for serving cell 705, the UE 115-b may receive a first group of SSBs from downlink TRP 720-c and a second group of SSBs from uplink TRP 715-c-2. Similarly, for the non-serving cell 710-a, the UE 115-b may receive a first group of SSBs from downlink TRP 720-a and a second group of SSBs from uplink TRP 715-a-1. And for the non-serving cell 710-b, the UE 115-b may receive a first group of SSBs from downlink TRP 720-b and a second group of SSBs from uplink TRP 715-b-2.
[0157] At processing operation 810, the UE 115-b may select a PCI. For example, the UE 115-a may select the PCI associated with the serving cell 705 (e.g., PCI C) , the PCI associated with the non-serving cell 710-a (PCI A) , or the PCI associated with the non-serving cell 710-b (e.g., PCI B) . The UE 115-b may select the PCI that has the highest RSRP metric. In a first alternative (Alternative 1) , the RSRP metric for a PCI may be an average RSRP, a weighted RSRP, a highest RSRP, or a lowest RSRP among the SSBs in the first and second SSB groups associated with the PCI. In a second alternative (Alternative 2) , the RSRP metric for a PCI may be an average RSRP, a weighted RSRP, a highest RSRP, or a lowest RSRP among the SSBs in the first SSB group associated with the PCI. In a third alternative (Alternative 3) , the RSRP metric for a PCI may be an average RSRP, a weighted RSRP, a highest RSRP, or a lowest RSRP among the SSBs in the second SSB group associated with the PCI. In a third alternative (Alternative 3) , the RSRP metric for a PCI may be the highest or lowest RSRP between Alternative 2 and Alternative 3. In some examples, the operations at 810 may be referred to as Step 1 of Option 5.
[0158] At processing operation 815, the UE 115-b may select an SSB from the SSB groups associated with the selected PCI. In some examples, the processing operation 815 may be referred to as Step 2 of Option 5.
[0159] In a first alternative (Alternative 1) , the UE 115-b first selects between the first and second groups of SSBs based on an RSRP threshold (e.g., rsrp-ThresholdSSB-Group) , then selects an SSB from the selected group using the SSB selection technique described with reference to FIG. 2. The RSRP threshold for SSB group selection may be configured by a higher layer (e.g., in an RRC message) or in a system information (e.g., SIB1) message. The RSRP threshold for SSB group selection may be commonly configured for different PCIs (e.g., a single RSRP threshold may be configured and applied for each PCI) or separately configured for different PCIs (e.g., respective separate RSRP thresholds may be configured and applied for each PCI) .
[0160] In a second alternative (Alternative 2) , the UE 115-b selects an SSB from the first and second SSB groups associated with the selected PCI based on a first RSRP threshold (e.g., rsrp-ThresholdSSB-FirstGroup) associated with the first SSB group and based on a second RSRP threshold associated with the second SSB group (e.g., rsrp-ThresholdSSB-SecondGroup) . The UE 115-b then selects an SSB from the selected group using the SSB selection technique described with reference to FIG. 2. The first and second RSRP thresholds for SSB group selection may be configured by a higher layer (e.g., in an RRC message) or in a system information message (e.g., SIB1) . The first RSRP threshold associated with the first SSB group may be commonly configured for different PCIs or separately configured for different PCIs. Similarly, the second RSRP threshold associated with the second SSB group may be commonly configured for different PCIs or separately configured for different PCIs.
[0161] At signaling operation 820, after selecting the SSB, the UE 115-b may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-b.
[0162] Thus, the UE 115-b may implement aspects of Option 5 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2.
[0163] FIG. 9 shows an example of a process flow 900 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 900 may be implemented by a UE such as the UE 115-b and may be described with reference to FIG. 7. The UE 115-b may implement aspects of the process flow 900 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2. The process flow 900 may be an example of a second option (Option 6) for selecting an SSB in Scenario 2. Thus, the process flow 900 may be implemented by the UE 115-b if the UE 115-b is configured with multiple SSB groups per cell.
[0164] At signaling operation 905, the UE 115-b may receive SSBs associated with different cells. For example, for serving cell 705, the UE 115-b may receive a first group of SSBs from downlink TRP 720-c and a second group of SSBs from uplink TRP 715-c-2. Similarly, for the non-serving cell 710-a, the UE 115-b may receive a first group of SSBs from downlink TRP 720-a and a second group of SSBs from uplink TRP 715-a-1. And for the non-serving cell 710-b, the UE 115-b may receive a first group of SSBs from downlink TRP 720-b and a second group of SSBs from uplink TRP 715-b-2.
[0165] At processing operation 910, the UE 115-b may select between the first groups of SSBs and the second groups of SSBs. That is, the UE 115-b may select between a superset of the first groups of SSBs and a superset of the second groups of SSBs, where the superset of the first groups of SSBs includes the first group of SSBs from each cell, and wherein the superset of the second groups of SSBs includes the second group of SSBs from each cell. In some examples, the operations at 910 may be referred to as Step 1 of Option 5. The UE 115-b may select between the first SSB groups and the second groups of SSBs based on an RSRP threshold for SSB group selection (e.g., rsrp-ThresholdSSB-Group) .
[0166] In a first alternative (Alternative 1) , the UE 115-b may select the first groups of SSBs unless an RSRP metric of the first groups of SSBs is less than the RSRP threshold. In the first alternative, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP among the SSBs in the first groups of SSBs across the PCIs.
[0167] In a second alternative (Alternative 2) , the UE 115-b may select the second groups of SSBs unless an RSRP metric of the second groups of SSBs is less than the RSRP threshold. In the second alternative, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP among the SSBs in the second groups of SSBs across the PCIs.
[0168] In a third alternative (Alternative 3) , the UE 115-b may select the second groups of SSBs unless a collective RSRP metric of the first and second groups of SSBs is less than the RSRP threshold. In the third alternative, the RSRP metric may be an average RSRP, a weighted RSRP, the highest RSRP, or the lowest RSRP among SSBs in the first and second SSB groups across the PCIs.
[0169] At processing operation 915, the UE 115-b may may select a PCI from the PCIs associated with the selected first or second group of SSBs. In some examples, the processing operation 915 may be referred to as Step 2 of Option 5. The UE 115-b may select the PCI based on the RSRP metric associated with each PCI. For example, the UE 115-b may select the PCI that has the highest associated RSRP metric. The RSRP metric for a PCI may be an average RSRP, a weighted RSRP, a highest RSRP, or a lowest RSRP among the SSBs in the selected SSB group associated with that PCI.
[0170] At processing operation 920, the UE 115-b may select an SSB from the selected group of SSBs associated with the selected PCI. The UE 115-b may select the SSB using the SSB selection technique described with reference to FIG. 2.
[0171] At signaling operation 925, after selecting the SSB, the UE 115-b may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-b.
[0172] Thus, the UE 115-b may implement aspects of Option 6 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2.
[0173] FIG. 10 shows an example of a process flow 1000 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 1000 may be implemented by a UE such as the UE 115-b and may be described with reference to FIG. 7. The UE 115-b may implement aspects of the process flow 1000 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2. The process flow 1000 may be an example of a third option (Option 7) for selecting an SSB in Scenario 2. Thus, the process flow 1000 may be implemented by the UE 115-b if the UE 115-b is configured with multiple SSB groups per cell.
[0174] At signaling operation 1005, the UE 115-b may receive SSBs associated with different cells. For example, for serving cell 705, the UE 115-b may receive a first group of SSBs from downlink TRP 720-c and a second group of SSBs from uplink TRP 715-c-2. Similarly, for the non-serving cell 710-a, the UE 115-b may receive a first group of SSBs from downlink TRP 720-a and a second group of SSBs from uplink TRP 715-a-1. And for the non-serving cell 710-b, the UE 115-b may receive a first group of SSBs from downlink TRP 720-b and a second group of SSBs from uplink TRP 715-b-2.
[0175] At processing operation 1010, the UE 115-b may select a PCI based on the PCI being indicated by a downlink control message (e.g., a DCI message) , which may trigger the random access procedure associated with the SSBs. For example, the SSBs may be part of a physical downlink control channel (PDCCH) -ordered random access procedure. The PCI may be indicated by one or more bits in the PDCCH associated with the DCI. For example, the one or more bits may indicate the PCI index.
[0176] At processing operation 1015, the UE 115-b may select an SSB from the SSB groups associated with the selected PCI. In a first alternative (Alternative 1) , the UE 115-b first selects between the first and second groups of SSBs based on an RSRP threshold (e.g., rsrp-ThresholdSSB-Group) , then selects an SSB from the selected group using the SSB selection technique described with reference to FIG. 2. The RSRP threshold for SSB group selection may be configured by a higher layer (e.g., in an RRC message) or in a system information message (e.g., SIB1) . The RSRP threshold for SSB group selection may be commonly configured for different PCIs (e.g., a single RSRP threshold may be configured and applied for each PCI) or separately configured for different PCIs (e.g., respective separate RSRP thresholds may be configured and applied for each PCI) .
[0177] In a second alternative (Alternative 2) , the UE 115-b selects an SSB from the first and second SSB groups associated with the selected PCI based on a first RSRP threshold (e.g., rsrp-ThresholdSSB-FirstGroup) associated with the first SSB group and based on a second RSRP threshold associated with the second SSB group (e.g., rsrp-ThresholdSSB-SecondGroup) . The UE 115-b then selects an SSB from the selected group using the SSB selection technique described with reference to FIG. 2. The first and second RSRP thresholds for SSB group selection may be configured by a higher layer (e.g., in an RRC message) or in a system information message (e.g., SIB1) . The first RSRP threshold associated with the first SSB group may be commonly configured for different PCIs or separately configured for different PCIs. Similarly, the second RSRP threshold associated with the second SSB group may be commonly configured for different PCIs or separately configured for different PCIs.
[0178] At signaling operation 1020, after selecting the SSB, the UE 115-b may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-b.
[0179] Thus, the UE 115-b may implement aspects of Option 7 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2.
[0180] FIG. 11 shows an example of a process flow 1100 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The process flow 1100 may be implemented by a UE such as the UE 115-b and may be described with reference to FIG. 7. The UE 115-b may implement aspects of the process flow 1100 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2. The process flow 1100 may be an example of a fourth option (Option 8) for selecting an SSB in Scenario 2. Thus, the process flow 1100 may be implemented by the UE 115-b if the UE 115-b is configured with multiple SSB groups per cell.
[0181] At signaling operation 1105, the UE 115-b may receive SSBs associated with different cells. For example, for serving cell 705, the UE 115-b may receive a first group of SSBs from downlink TRP 720-c and a second group of SSBs from uplink TRP 715-c-2. Similarly, for the non-serving cell 710-a, the UE 115-b may receive a first group of SSBs from downlink TRP 720-a and a second group of SSBs from uplink TRP 715-a-1. And for the non-serving cell 710-b, the UE 115-b may receive a first group of SSBs from downlink TRP 720-b and a second group of SSBs from uplink TRP 715-b-2.
[0182] At processing operation 1110, the UE 115-b may select a PCI based on the PCI being indicated by a downlink control message (e.g., a DCI message) , which may trigger the random access procedure associated with the SSBs. The UE 115-b may also select an SSB group (e.g., either the first group of SSBs or the second group of SSBs) associated with the PCI based on the SSB group being indicated by the downlink control message. For example, the SSBs may be part of a physical downlink control channel (PDCCH) -ordered random access procedure. In a first alternative (Alternative 1) , a single field may be used to indicate both the PCI and the SSB group, where each codepoint of the field is mapped to the PCI index and the SSB group index. In a second alternative (Alternative 2) , two fields may be used to indicate the PCI and the SSB group, where one field is used to indicate the PCI index, and the other field is used to indicate the SSB group index.
[0183] At processing operation 1115, the UE 115-b may select an SSB from the selected SSB group. For example, the UE 115-b may select the SSB using the SSB selection technique described with reference to FIG. 2.
[0184] At signaling operation 1120, after selecting the SSB, the UE 115-b may transmit a random access preamble in one or more random access (e.g., PRACH) resources associated with the selected SSB. The network may then use information in the random access preamble to establish a connection with the UE 115-b.
[0185] Thus, the UE 115-b may implement aspects of Option 8 to select an SSB for a random access procedure in an inter-cell scenario such as Scenario 2.
[0186] FIG. 12 shows a block diagram 1200 of a device 1205 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The device 1205 may be an example of aspects of a UE 115 as described herein. The device 1205 may include a receiver 1210, a transmitter 1215, and a communications manager 1220. The device 1205, or one or more components of the device 1205 (e.g., the receiver 1210, the transmitter 1215, the communications manager 1220) , may include at least one processor, which may be coupled with at least one memory, to, individually or collectively, support or enable the described techniques. Each of these components may be in communication with one another (e.g., via one or more buses) .
[0187] The receiver 1210 may provide a 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 SSB selection in an inter-cell wireless communications system) . Information may be passed on to other components of the device 1205. The receiver 1210 may utilize a single antenna or a set of multiple antennas.
[0188] The transmitter 1215 may provide a means for transmitting signals generated by other components of the device 1205. For example, the transmitter 1215 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 SSB selection in an inter-cell wireless communications system) . In some examples, the transmitter 1215 may be co-located with a receiver 1210 in a transceiver module. The transmitter 1215 may utilize a single antenna or a set of multiple antennas.
[0189] The communications manager 1220, the receiver 1210, the transmitter 1215, or various combinations or components thereof may be examples of means for performing various aspects of SSB selection in an inter-cell wireless communications system as described herein. For example, the communications manager 1220, the receiver 1210, the transmitter 1215, or various combinations or components thereof may be capable of performing one or more of the functions described herein.
[0190] In some examples, the communications manager 1220, the receiver 1210, the transmitter 1215, or various combinations or components thereof may be implemented in hardware (e.g., in communications management circuitry) . The hardware may include at least one of 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 configured as or otherwise supporting, individually or collectively, a means for performing the functions described in the present disclosure. In some examples, at least one processor and at least one memory coupled with the at least one processor may be configured to perform one or more of the functions described herein (e.g., by one or more processors, individually or collectively, executing instructions stored in the at least one memory) .
[0191] Additionally, or alternatively, the communications manager 1220, the receiver 1210, the transmitter 1215, or various combinations or components thereof may be implemented in code (e.g., as communications management software or firmware) executed by at least one processor (e.g., referred to as a processor-executable code) . If implemented in code executed by at least one processor, the functions of the communications manager 1220, the receiver 1210, the transmitter 1215, or various combinations or components thereof may be performed by a general-purpose processor, a DSP, a CPU, an ASIC, an FPGA, a microcontroller, or any combination of these or other programmable logic devices (e.g., configured as or otherwise supporting, individually or collectively, a means for performing the functions described in the present disclosure) .
[0192] In some examples, the communications manager 1220 may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1210, the transmitter 1215, or both. For example, the communications manager 1220 may receive information from the receiver 1210, send information to the transmitter 1215, or be integrated in combination with the receiver 1210, the transmitter 1215, or both to obtain information, output information, or perform various other operations as described herein.
[0193] The communications manager 1220 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1220 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds. The communications manager 1220 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0194] Additionally, or alternatively, the communications manager 1220 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1220 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for receiving a DCI message triggering a random access procedure and indicating one or more of the first PCI or the second PCI. The communications manager 1220 is capable of, configured to, or operable to support a means for transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the DCI message.
[0195] Additionally, or alternatively, the communications manager 1220 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1220 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP. The communications manager 1220 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0196] By including or configuring the communications manager 1220 in accordance with examples as described herein, the device 1205 (e.g., at least one processor controlling or otherwise coupled with the receiver 1210, the transmitter 1215, the communications manager 1220, or a combination thereof) may support techniques for more efficient utilization of communication resources.
[0197] FIG. 13 shows a block diagram 1300 of a device 1305 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The device 1305 may be an example of aspects of a device 1205 or a UE 115 as described herein. The device 1305 may include a receiver 1310, a transmitter 1315, and a communications manager 1320. The device 1305, or one or more components of the device 1305 (e.g., the receiver 1310, the transmitter 1315, the communications manager 1320) , may include at least one processor, which may be coupled with at least one memory, to support the described techniques. Each of these components may be in communication with one another (e.g., via one or more buses) .
[0198] The receiver 1310 may provide a 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 SSB selection in an inter-cell wireless communications system) . Information may be passed on to other components of the device 1305. The receiver 1310 may utilize a single antenna or a set of multiple antennas.
[0199] The transmitter 1315 may provide a means for transmitting signals generated by other components of the device 1305. For example, the transmitter 1315 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 SSB selection in an inter-cell wireless communications system) . In some examples, the transmitter 1315 may be co-located with a receiver 1310 in a transceiver module. The transmitter 1315 may utilize a single antenna or a set of multiple antennas.
[0200] The device 1305, or various components thereof, may be an example of means for performing various aspects of SSB selection in an inter-cell wireless communications system as described herein. For example, the communications manager 1320 may include an SSB component 1325, a selection component 1330, a preamble component 1335, a DCI component 1340, or any combination thereof. The communications manager 1320 may be an example of aspects of a communications manager 1220 as described herein. In some examples, the communications manager 1320, or various components thereof, may be configured to perform various operations (e.g., receiving, obtaining, monitoring, outputting, transmitting) using or otherwise in cooperation with the receiver 1310, the transmitter 1315, or both. For example, the communications manager 1320 may receive information from the receiver 1310, send information to the transmitter 1315, or be integrated in combination with the receiver 1310, the transmitter 1315, or both to obtain information, output information, or perform various other operations as described herein.
[0201] The communications manager 1320 may support wireless communications in accordance with examples as disclosed herein. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP. The selection component 1330 is capable of, configured to, or operable to support a means for selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds. The preamble component 1335 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0202] Additionally, or alternatively, the communications manager 1320 may support wireless communications in accordance with examples as disclosed herein. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The DCI component 1340 is capable of, configured to, or operable to support a means for receiving a DCI message triggering a random access procedure and indicating one or more of the first PCI or the second PCI. The preamble component 1335 is capable of, configured to, or operable to support a means for transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the DCI message.
[0203] Additionally, or alternatively, the communications manager 1320 may support wireless communications in accordance with examples as disclosed herein. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The SSB component 1325 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP. The preamble component 1335 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0204] FIG. 14 shows a block diagram 1400 of a communications manager 1420 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The communications manager 1420 may be an example of aspects of a communications manager 1220, a communications manager 1320, or both, as described herein. The communications manager 1420, or various components thereof, may be an example of means for performing various aspects of SSB selection in an inter-cell wireless communications system as described herein. For example, the communications manager 1420 may include an SSB component 1425, a selection component 1430, a preamble component 1435, a DCI component 1440, a comparison component 1445, an RSRP component 1450, or any combination thereof. Each of these components, or components or subcomponents thereof (e.g., one or more processors, one or more memories) , may communicate, directly or indirectly, with one another (e.g., via one or more buses) .
[0205] The communications manager 1420 may support wireless communications in accordance with examples as disclosed herein. The SSB component 1425 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. In some examples, the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP. The selection component 1430 is capable of, configured to, or operable to support a means for selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds. The preamble component 1435 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0206] In some examples, the one or more RSRP thresholds include a RSRP threshold associated with the serving cell and the one or more non-serving cells, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, the second set of SSBs, or both, where the first set of SSBs or the second set of SSBs is selected based on the comparison.
[0207] In some examples, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the one or more non-serving cells, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs. In some examples, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the one or more non-serving cells, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, where the first set of SSBs or the second set of SSBs is selected based on the comparisons.
[0208] In some examples, the one or more non-serving cells include a first non-serving cell and a second non-serving cell, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting the first non-serving cell based on the selection of the second set of SSBs, where the SSB is selected based on being associated with the first non-serving cell.
[0209] In some examples, the second set of SSBs is associated with a first non-serving cell that has a second PCI, and the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a third set of SSBs associated with a second non-serving cell that has a third PCI. In some examples, the second set of SSBs is associated with a first non-serving cell that has a second PCI, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting the second set of SSBs from among the second set of SSBs and the third set of SSBs, where the first set of SSBs or the second set of SSBs is selected based on the selection of the second set of SSBs.
[0210] In some examples, the one or more RSRP thresholds include a RSRP threshold, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, where the first set of SSBs or the second set of SSBs is selected based on the comparison.
[0211] In some examples, the one or more RSRP thresholds include a RSRP threshold associated with the serving cell and the one or more non-serving cells, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs or the second set of SSBs, where the first set of SSBs or the second set of SSBs is selected based on the comparison.
[0212] In some examples, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the first non-serving cell, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs. In some examples, the one or more RSRP thresholds include a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the first non-serving cell, and the comparison component 1445 is capable of, configured to, or operable to support a means for comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, where the first set of SSBs or the second set of SSBs is selected based on the comparisons.
[0213] In some examples, the one or more non-serving cells includes a non-serving cell that has a second PCI. In some examples, the one or more RSRP thresholds include a first RSRP threshold associated with the first PCI and a second RSRP threshold associated with the second PCI.
[0214] In some examples, the SSB is of the first set of SSBs, and the RSRP component 1450 is capable of, configured to, or operable to support a means for determining that a RSRP metric associated with the SSB satisfies the first RSRP threshold, where the SSB is selected based on the determination.
[0215] In some examples, the SSB is of the second set of SSBs, and the RSRP component 1450 is capable of, configured to, or operable to support a means for determining that a RSRP metric associated with the SSB satisfies the second RSRP threshold, where the SSB is selected based on the determination.
[0216] Additionally, or alternatively, the communications manager 1420 may support wireless communications in accordance with examples as disclosed herein. In some examples, the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. In some examples, the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The DCI component 1440 is capable of, configured to, or operable to support a means for receiving a DCI message triggering a random access procedure and indicating one or more of the first PCI or the second PCI. In some examples, the preamble component 1435 is capable of, configured to, or operable to support a means for transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the DCI message.
[0217] In some examples, the DCI message indicates one or more of the first PCI or the second PCI via one or more cell indicator fields.
[0218] In some examples, the DCI message indicates the first PCI and the second PCI, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI and the second PCI based on a RSRP threshold.
[0219] In some examples, the DCI message indicates the first PCI and the second PCI, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI and the second PCI based on a first RSRP threshold associated with the first PCI and based on a second RSRP threshold associated with the second PCI.
[0220] Additionally, or alternatively, the communications manager 1420 may support wireless communications in accordance with examples as disclosed herein. In some examples, the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. In some examples, the SSB component 1425 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP. In some examples, the preamble component 1435 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0221] In some examples, the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI or the second PCI, where the SSB is selected from the first set of SSBs or the second set of SSBs based on the selection of the first PCI or the second PCI.
[0222] In some examples, the selection component 1430 is capable of, configured to, or operable to support a means for selecting between a first superset of SSBs and a second superset of SSBs, where the first superset includes the first subset of SSBs and the third subset of SSBs, and where the second superset includes the second subset of SSBs and the fourth subset of SSBs. In some examples, the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI or the second PCI based on the selection between the first superset and the second superset, where the SSB is selected based on the selection of the first PCI or the second PCI.
[0223] In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI or the second PCI based on the downlink control message including an indication of the first PCI or the second PCI. In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting, based on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based on one or more RSRP thresholds. In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting, based on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based on the one or more RSRP thresholds.
[0224] In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting between the first PCI or the second PCI based on the downlink control message including an indication of the first PCI or the second PCI. In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting, based on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based on the downlink control message including an indication of the first subset or the second subset. In some examples, the random access preamble is associated with a random access procedure triggered by a DCI message, and the selection component 1430 is capable of, configured to, or operable to support a means for selecting, based on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based on the downlink control message including an indication of the third subset or the fourth subset.
[0225] FIG. 15 shows a diagram of a system 1500 including a device 1505 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The device 1505 may be an example of or include components of a device 1205, a device 1305, or a UE 115 as described herein. The device 1505 may communicate (e.g., wirelessly) with one or more other devices (e.g., network entities 105, UEs 115, or a combination thereof) . The device 1505 may include components for bi-directional voice and data communications including components for transmitting and receiving communications, such as a communications manager 1520, an input / output (I / O) controller, such as an I / O controller 1510, a transceiver 1515, one or more antennas 1525, at least one memory 1530, code 1535, and at least one processor 1540. These components may be in electronic communication or otherwise coupled (e.g., operatively, communicatively, functionally, electronically, electrically) via one or more buses (e.g., a bus 1545) .
[0226] The I / O controller 1510 may manage input and output signals for the device 1505. The I / O controller 1510 may also manage peripherals not integrated into the device 1505. In some cases, the I / O controller 1510 may represent a physical connection or port to an external peripheral. In some cases, the I / O controller 1510 may utilize an operating system such as or another known operating system. Additionally, or alternatively, the I / O controller 1510 may represent or interact with a modem, a keyboard, a mouse, a touchscreen, or a similar device. In some cases, the I / O controller 1510 may be implemented as part of one or more processors, such as the at least one processor 1540. In some cases, a user may interact with the device 1505 via the I / O controller 1510 or via hardware components controlled by the I / O controller 1510.
[0227] In some cases, the device 1505 may include a single antenna. However, in some other cases, the device 1505 may have more than one antenna, which may be capable of concurrently transmitting or receiving multiple wireless transmissions. The transceiver 1515 may communicate bi-directionally via the one or more antennas 1525 using wired or wireless links as described herein. For example, the transceiver 1515 may represent a wireless transceiver and may communicate bi-directionally with another wireless transceiver. The transceiver 1515 may also include a modem to modulate the packets, to provide the modulated packets to one or more antennas 1525 for transmission, and to demodulate packets received from the one or more antennas 1525. The transceiver 1515, or the transceiver 1515 and one or more antennas 1525, may be an example of a transmitter 1215, a transmitter 1315, a receiver 1210, a receiver 1310, or any combination thereof or component thereof, as described herein.
[0228] The at least one memory 1530 may include random access memory (RAM) and read-only memory (ROM) . The at least one memory 1530 may store computer-readable, computer-executable, or processor-executable code, such as the code 1535. The code 1535 may include instructions that, when executed by the at least one processor 1540, cause the device 1505 to perform various functions described herein. The code 1535 may be stored in a non-transitory computer-readable medium such as system memory or another type of memory. In some cases, the code 1535 may not be directly executable by the at least one processor 1540 but may cause a computer (e.g., when compiled and executed) to perform functions described herein. In some cases, the at least one memory 1530 may include, among other things, a basic I / O system (BIOS) which may control basic hardware or software operation such as the interaction with peripheral components or devices.
[0229] The at least one processor 1540 may include one or more intelligent hardware devices (e.g., one or more general-purpose processors, one or more DSPs, one or more CPUs, one or more graphics processing units (GPUs) , one or more neural processing units (NPUs) (also referred to as neural network processors or deep learning processors (DLPs) ) , one or more microcontrollers, one or more ASICs, one or more FPGAs, one or more programmable logic devices, discrete gate or transistor logic, one or more discrete hardware components, or any combination thereof) . In some cases, the at least one processor 1540 may be configured to operate a memory array using a memory controller. In some other cases, a memory controller may be integrated into the at least one processor 1540. The at least one processor 1540 may be configured to execute computer-readable instructions stored in a memory (e.g., the at least one memory 1530) to cause the device 1505 to perform various functions (e.g., functions or tasks supporting SSB selection in an inter-cell wireless communications system) . For example, the device 1505 or a component of the device 1505 may include at least one processor 1540 and at least one memory 1530 coupled with or to the at least one processor 1540, the at least one processor 1540 and the at least one memory 1530 configured to perform various functions described herein.
[0230] In some examples, the at least one processor 1540 may include multiple processors and the at least one memory 1530 may include multiple memories. One or more of the multiple processors may be coupled with one or more of the multiple memories, which may, individually or collectively, be configured to perform various functions described herein. In some examples, the at least one processor 1540 may be a component of a processing system, which may refer to a system (such as a series) of machines, circuitry (including, for example, one or both of processor circuitry (which may include the at least one processor 1540) and memory circuitry (which may include the at least one memory 1530) ) , or components, that receives or obtains inputs and processes the inputs to produce, generate, or obtain a set of outputs. The processing system may be configured to perform one or more of the functions described herein. For example, the at least one processor 1540 or a processing system including the at least one processor 1540 may be configured to, configurable to, or operable to cause the device 1505 to perform one or more of the functions described herein. Further, as described herein, being “configured to, ” being “configurable to, ” and being “operable to” may be used interchangeably and may be associated with a capability, when executing code 1535 (e.g., processor-executable code) stored in the at least one memory 1530 or otherwise, to perform one or more of the functions described herein.
[0231] The communications manager 1520 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1520 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds. The communications manager 1520 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs.
[0232] Additionally, or alternatively, the communications manager 1520 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1520 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for receiving a DCI message triggering a random access procedure and indicating one or more of the first PCI or the second PCI. The communications manager 1520 is capable of, configured to, or operable to support a means for transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the DCI message.
[0233] Additionally, or alternatively, the communications manager 1520 may support wireless communications in accordance with examples as disclosed herein. For example, the communications manager 1520 is capable of, configured to, or operable to support a means for receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP. The communications manager 1520 is capable of, configured to, or operable to support a means for transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0234] By including or configuring the communications manager 1520 in accordance with examples as described herein, the device 1505 may support techniques for more efficient utilization of communication resources.
[0235] In some examples, the communications manager 1520 may be configured to perform various operations (e.g., receiving, monitoring, transmitting) using or otherwise in cooperation with the transceiver 1515, the one or more antennas 1525, or any combination thereof. Although the communications manager 1520 is illustrated as a separate component, in some examples, one or more functions described with reference to the communications manager 1520 may be supported by or performed by the at least one processor 1540, the at least one memory 1530, the code 1535, or any combination thereof. For example, the code 1535 may include instructions executable by the at least one processor 1540 to cause the device 1505 to perform various aspects of SSB selection in an inter-cell wireless communications system as described herein, or the at least one processor 1540 and the at least one memory 1530 may be otherwise configured to, individually or collectively, perform or support such operations.
[0236] FIG. 16 shows a flowchart illustrating a method 1600 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The operations of the method 1600 may be implemented by a UE or its components as described herein. For example, the operations of the method 1600 may be performed by a UE 115 as described with reference to FIGs. 1 through 15. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally, or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.
[0237] At 1605, the method may include receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The operations of 1605 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1605 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0238] At 1610, the method may include receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP. The operations of 1610 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1610 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0239] At 1615, the method may include selecting the first set of SSBs or the second set of SSBs based on one or more RSRP thresholds. The operations of 1615 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1615 may be performed by a selection component 1430 as described with reference to FIG. 14.
[0240] At 1620, the method may include transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the selection of the first set of SSBs or the second set of SSBs. The operations of 1620 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1620 may be performed by a preamble component 1435 as described with reference to FIG. 14.
[0241] FIG. 17 shows a flowchart illustrating a method 1700 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The operations of the method 1700 may be implemented by a UE or its components as described herein. For example, the operations of the method 1700 may be performed by a UE 115 as described with reference to FIGs. 1 through 15. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally, or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.
[0242] At 1705, the method may include receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP. The operations of 1705 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1705 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0243] At 1710, the method may include receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The operations of 1710 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1710 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0244] At 1715, the method may include receiving a DCI message triggering a random access procedure and indicating one or more of the first PCI or the second PCI. The operations of 1715 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1715 may be performed by a DCI component 1440 as described with reference to FIG. 14.
[0245] At 1720, the method may include transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based on the DCI message. The operations of 1720 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1720 may be performed by a preamble component 1435 as described with reference to FIG. 14.
[0246] FIG. 18 shows a flowchart illustrating a method 1800 that supports SSB selection in an inter-cell wireless communications system in accordance with one or more aspects of the present disclosure. The operations of the method 1800 may be implemented by a UE or its components as described herein. For example, the operations of the method 1800 may be performed by a UE 115 as described with reference to FIGs. 1 through 15. In some examples, a UE may execute a set of instructions to control the functional elements of the UE to perform the described functions. Additionally, or alternatively, the UE may perform aspects of the described functions using special-purpose hardware.
[0247] At 1805, the method may include receiving a first set of SSBs associated with a serving cell that has a first PCI, where the first set of SSBs includes a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP. The operations of 1805 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1805 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0248] At 1810, the method may include receiving a second set of SSBs associated with a non-serving cell that has a second PCI, where the second set of SSBs includes a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP. The operations of 1810 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1810 may be performed by an SSB component 1425 as described with reference to FIG. 14.
[0249] At 1815, the method may include transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs. The operations of 1815 may be performed in accordance with examples as disclosed herein. In some examples, aspects of the operations of 1815 may be performed by a preamble component 1435 as described with reference to FIG. 14.
[0250] The following provides an overview of aspects of the present disclosure:
[0251] Aspect 1: A method for wireless communications at a UE, comprising: receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP; receiving a second set of SSBs associated with one or more non-serving cells that each have a respective PCI different from the first PCI, the second set of SSBs received from one or more TRPs that have reduced downlink capabilities relative to the first TRP; selecting the first set of SSBs or the second set of SSBs based at least in part on one or more RSRP thresholds; and transmitting a random access preamble in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based at least in part on the selection of the first set of SSBs or the second set of SSBs.
[0252] Aspect 2: The method of aspect 1, wherein the one or more RSRP thresholds comprise a RSRP threshold associated with the serving cell and the one or more non-serving cells, the method further comprising: comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, the second set of SSBs, or both, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the comparison.
[0253] Aspect 3: The method of any of aspects 1 through 2, wherein the one or more RSRP thresholds comprise a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the one or more non-serving cells, the method further comprising: comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs; and comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the comparisons.
[0254] Aspect 4: The method of any of aspects 1 through 3, wherein the one or more non-serving cells comprise a first non-serving cell and a second non-serving cell, and wherein the second set of SSBs is selected, the method further comprising: selecting the first non-serving cell based at least in part on the selection of the second set of SSBs, wherein the SSB is selected based at least in part on being associated with the first non-serving cell.
[0255] Aspect 5: The method of any of aspects 1 through 4, wherein the second set of SSBs is associated with a first non-serving cell that has a second PCI, the method further comprising: receiving a third set of SSBs associated with a second non-serving cell that has a third PCI; and selecting the second set of SSBs from among the second set of SSBs and the third set of SSBs, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the selection of the second set of SSBs.
[0256] Aspect 6: The method of aspect 5, wherein the one or more RSRP thresholds comprise a RSRP threshold, the method further comprising: comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the comparison.
[0257] Aspect 7: The method of any of aspects 5 through 6, wherein the one or more RSRP thresholds comprise a RSRP threshold associated with the serving cell and the one or more non-serving cells, the method further comprising: comparing the RSRP threshold with a RSRP metric associated with the first set of SSBs or the second set of SSBs, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the comparison.
[0258] Aspect 8: The method of any of aspects 5 through 7, wherein the one or more RSRP thresholds comprise a first RSRP threshold associated with the serving cell and a second RSRP threshold associated with the first non-serving cell, the method further comprising: comparing the first RSRP threshold with a first RSRP metric associated with the first set of SSBs; and comparing the second RSRP threshold with a second RSRP metric associated with the second set of SSBs, wherein the first set of SSBs or the second set of SSBs is selected based at least in part on the comparisons.
[0259] Aspect 9: The method of any of aspects 1 through 8, wherein the one or more non-serving cells comprises a non-serving cell that has a second PCI, and the one or more RSRP thresholds comprise a first RSRP threshold associated with the first PCI and a second RSRP threshold associated with the second PCI.
[0260] Aspect 10: The method of aspect 9, wherein the SSB is of the first set of SSBs, the method further comprising: determining that a RSRP metric associated with the SSB satisfies the first RSRP threshold, wherein the SSB is selected based at least in part on the determination.
[0261] Aspect 11: The method of any of aspects 9 through 10, wherein the SSB is of the second set of SSBs, the method further comprising: determining that a RSRP metric associated with the SSB satisfies the second RSRP threshold, wherein the SSB is selected based at least in part on the determination.
[0262] Aspect 12: A method for wireless communications at a UE, comprising: receiving a first set of SSBs associated with a serving cell that has a first PCI, the first set of SSBs received from a first TRP; receiving a second set of SSBs associated with a non-serving cell that has a second PCI different from the first PCI, the second set of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP; receiving a downlink control information message triggering a random access procedure and indicating one or more of the first PCI or the second PCI; and transmitting a random access preamble associated with the random access procedure in a random access resource associated with a SSB selected from either the first set of SSBs or the second set of SSBs based at least in part on the downlink control information message.
[0263] Aspect 13: The method of aspect 12, wherein the downlink control information message indicates one or more of the first PCI or the second PCI via one or more cell indicator fields.
[0264] Aspect 14: The method of any of aspects 12 through 13, wherein the downlink control information message indicates the first PCI and the second PCI, the method further comprising: selecting between the first PCI and the second PCI based at least in part on a RSRP threshold.
[0265] Aspect 15: The method of any of aspects 12 through 14, wherein the downlink control information message indicates the first PCI and the second PCI, the method further comprising: selecting between the first PCI and the second PCI based at least in part on a first RSRP threshold associated with the first PCI and based at least in part on a second RSRP threshold associated with the second PCI.
[0266] Aspect 16: A method for wireless communications at a UE, comprising: receiving a first set of SSBs associated with a serving cell that has a first PCI, wherein the first set of SSBs comprises a first subset of SSBs received from a first TRP and a second subset of SSBs received from a second TRP that has reduced downlink capabilities relative to the first TRP; receiving a second set of SSBs associated with a non-serving cell that has a second PCI, wherein the second set of SSBs comprises a third subset of SSBs received from a third TRP and a fourth subset of SSBs received from a fourth TRP that has reduced downlink capabilities relative to the third TRP; and transmitting a random access preamble in a random access resource associated with a SSB selected from the first set of SSBs or the second set of SSBs.
[0267] Aspect 17: The method of aspect 16, further comprising: selecting between the first PCI or the second PCI, wherein the SSB is selected from the first set of SSBs or the second set of SSBs based at least in part on the selection of the first PCI or the second PCI.
[0268] Aspect 18: The method of any of aspects 16 through 17, further comprising: selecting between a first superset of SSBs and a second superset of SSBs, wherein the first superset comprises the first subset of SSBs and the third subset of SSBs, and wherein the second superset comprises the second subset of SSBs and the fourth subset of SSBs; and selecting between the first PCI or the second PCI based at least in part on the selection between the first superset and the second superset, wherein the SSB is selected based at least in part on the selection of the first PCI or the second PCI.
[0269] Aspect 19: The method of any of aspects 16 through 18, wherein the random access preamble is associated with a random access procedure triggered by downlink control message, the method further comprising: selecting between the first PCI or the second PCI based at least in part on the downlink control message comprising an indication of the first PCI or the second PCI; and selecting, based at least in part on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based at least in part on one or more RSRP thresholds; or selecting, based at least in part on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based at least in part on the one or more RSRP thresholds.
[0270] Aspect 20: The method of any of aspects 16 through 19, wherein the random access preamble is associated with a random access procedure triggered by downlink control message, the method further comprising: selecting between the first PCI or the second PCI based at least in part on the downlink control message comprising an indication of the first PCI or the second PCI; and selecting, based at least in part on the selection of the first PCI, between the first subset of SSBs and the second subset of SSBs based at least in part on the downlink control message comprising an indication of the first subset or the second subset; or selecting, based at least in part on the selection of the second PCI, between the third subset of SSBs and the fourth subset of SSBs based at least in part on the downlink control message comprising an indication of the third subset or the fourth subset.
[0271] Aspect 21: A UE for wireless communications, comprising one or more memories storing processor-executable code, and one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to perform a method of any of aspects 1 through 11.
[0272] Aspect 22: A UE for wireless communications, comprising at least one means for performing a method of any of aspects 1 through 11.
[0273] Aspect 23: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by one or more processors to perform a method of any of aspects 1 through 11.
[0274] Aspect 24: A UE for wireless communications, comprising one or more memories storing processor-executable code, and one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to perform a method of any of aspects 12 through 15.
[0275] Aspect 25: A UE for wireless communications, comprising at least one means for performing a method of any of aspects 12 through 15.
[0276] Aspect 26: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by one or more processors to perform a method of any of aspects 12 through 15.
[0277] Aspect 27: A UE for wireless communications, comprising one or more memories storing processor-executable code, and one or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to perform a method of any of aspects 16 through 20.
[0278] Aspect 28: A UE for wireless communications, comprising at least one means for performing a method of any of aspects 16 through 20.
[0279] Aspect 29: A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by one or more processors to perform a method of any of aspects 16 through 20.
[0280] It should be noted that the methods described herein describe possible implementations. The operations and the steps may be rearranged or otherwise modified and other implementations are possible. Further, aspects from two or more of the methods may be combined.
[0281] Although aspects of an LTE, LTE-A, LTE-A Pro, or NR system may be described for purposes of example, and LTE, LTE-A, LTE-A Pro, or NR terminology may be used in much of the description, the techniques described herein are applicable beyond LTE, LTE-A, LTE-A Pro, or NR networks. For example, the described techniques may be applicable to various other wireless communications 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, as well as other systems and radio technologies not explicitly mentioned herein.
[0282] Information and signals described herein may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.
[0283] The various illustrative blocks and components described in connection with the disclosure herein may be implemented or performed using a general-purpose processor, a DSP, an ASIC, a CPU, a graphics processing unit (GPU) , a neural processing unit (NPU) , an 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 the alternative, the processor may be any processor, controller, microcontroller, or state machine. A 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) . Any functions or operations described herein as being capable of being performed by a processor may be performed by multiple processors that, individually or collectively, are capable of performing the described functions or operations.
[0284] The functions described herein may be implemented using hardware, software executed by a processor, firmware, or any combination thereof. If implemented using software executed by a processor, the functions may be stored as or transmitted using one or more instructions or code of a computer-readable medium. Other examples and implementations are within the scope of the disclosure and appended claims. For example, due to the nature of software, functions described herein may be implemented using software executed by a processor, hardware, firmware, hardwiring, or combinations of any of these. Features implementing functions may also be physically located at various positions, including being distributed such that portions of functions are implemented at different physical locations.
[0285] Computer-readable media includes both non-transitory computer storage media and communication media including any medium that facilitates transfer of a computer program from one location to another. A non-transitory storage medium may be any available medium that may be accessed by a general-purpose or special-purpose computer. By way of example, and not limitation, non-transitory computer-readable media may include RAM, ROM, electrically erasable programmable ROM (EEPROM) , flash memory, compact disk (CD) ROM or other optical disk storage, magnetic disk storage or other magnetic storage devices, or any other non-transitory medium that may be used to carry or store desired program code means in the form of instructions or data structures and that may be accessed by a general-purpose or special-purpose computer or a general-purpose or special-purpose processor. Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared, radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of computer-readable medium. Disk and disc, as used herein, include CD, laser disc, optical disc, digital versatile disc (DVD) , floppy disk, and Blu-ray disc. Disks may reproduce data magnetically, and discs may reproduce data optically using lasers. Combinations of the above are also included within the scope of computer-readable media. Any functions or operations described herein as being capable of being performed by a memory may be performed by multiple memories that, individually or collectively, are capable of performing the described functions or operations.
[0286] As used herein, including in the claims, “or” as used in a list of items (e.g., a list of items prefaced by a phrase such as “at least one of” or “one or more of” ) indicates an inclusive list such 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) . Also, as used herein, the phrase “based on” shall not be construed as a reference to a closed set of conditions. For example, an example step that is described as “based on condition A” may be based on both a condition A and a condition B without departing from the scope of the present disclosure. In other words, as used herein, the phrase “based on” shall be construed in the same manner as the phrase “based at least in part on. ”
[0287] As used herein, including in the claims, the article “a” before a noun is open-ended and understood to refer to “at least one” of those nouns or “one or more” of those nouns. Thus, the terms “a, ” “at least one, ” “one or more, ” and “at least one of one or more” may be interchangeable. For example, if a claim recites “a component” that performs one or more functions, each of the individual functions may be performed by a single component or by any combination of multiple components. Thus, the term “a component” having characteristics or performing functions may refer to “at least one of one or more components” having a particular characteristic or performing a particular function. Subsequent reference to a component introduced with the article “a” using the terms “the” or “said” may refer to any or all of the one or more components. For example, a component introduced with the article “a” may be understood to mean “one or more components, ” and referring to “the component” subsequently in the claims may be understood to be equivalent to referring to “at least one of the one or more components. ” Similarly, subsequent reference to a component introduced as “one or more components” using the terms “the” or “said” may refer to any or all of the one or more components. For example, referring to “the one or more components” subsequently in the claims may be understood to be equivalent to referring to “at least one of the one or more components. ”
[0288] The term “determine” or “determining” encompasses a variety of actions and, therefore, “determining” can include calculating, computing, processing, deriving, investigating, looking up (such as via looking up in a table, a database, or another data structure) , ascertaining, and the like. Also, “determining” can include receiving (e.g., receiving information) , accessing (e.g., accessing data stored in memory) , and the like. Also, “determining” can include resolving, obtaining, selecting, choosing, establishing, and other such similar actions.
[0289] In the appended figures, similar components or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label by a dash and a second label that distinguishes among the similar components. If just the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label or other subsequent reference label.
[0290] The description set forth herein, in connection with the appended drawings, describes example configurations and does not represent all the examples that may be implemented or that are within the scope of the claims. The term “example” used herein means “serving as an example, instance, or illustration” and not “preferred” or “advantageous over other examples. ” The detailed description includes specific details for the purpose of providing an understanding of the described techniques. These techniques, however, may be practiced without these specific details. In some figures, known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the described examples.
[0291] The description herein is provided to enable a person having ordinary skill in the art to make or use the disclosure. Various modifications to the disclosure will be apparent to a person having ordinary skill in the art, and the generic principles defined herein may be applied to other variations without departing from the scope of the disclosure. Thus, the disclosure is not limited to the examples and designs described herein but is to be accorded the broadest scope consistent with the principles and novel features disclosed herein.
Claims
1.A user equipment (UE) , comprising:one or more memories storing processor-executable code; andone or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to:receive a first set of synchronization signal blocks associated with a serving cell that has a first physical cell identifier, the first set of synchronization signal blocks received from a first transmission-reception point;receive a second set of synchronization signal blocks associated with one or more non-serving cells that each have a respective physical cell identifier different from the first physical cell identifier, the second set of synchronization signal blocks received from one or more transmission-reception points that have reduced downlink capabilities relative to the first transmission-reception point;select the first set of synchronization signal blocks or the second set of synchronization signal blocks based at least in part on one or more reference signal received power thresholds; andtransmit a random access preamble in a random access resource associated with a synchronization signal block selected from either the first set of synchronization signal blocks or the second set of synchronization signal blocks based at least in part on the selection of the first set of synchronization signal blocks or the second set of synchronization signal blocks.2.The UE of claim 1, wherein the one or more reference signal received power thresholds comprise a reference signal received power threshold associated with the serving cell and the one or more non-serving cells, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:compare the reference signal received power threshold with a reference signal received power metric associated with the first set of synchronization signal blocks, the second set of synchronization signal blocks, or both, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the comparison.3.The UE of claim 1, wherein the one or more reference signal received power thresholds comprise a first reference signal received power threshold associated with the serving cell and a second reference signal received power threshold associated with the one or more non-serving cells, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:compare the first reference signal received power threshold with a first reference signal received power metric associated with the first set of synchronization signal blocks; andcompare the second reference signal received power threshold with a second reference signal received power metric associated with the second set of synchronization signal blocks, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the comparisons.4.The UE of claim 1, wherein the one or more non-serving cells comprise a first non-serving cell and a second non-serving cell, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select the first non-serving cell based at least in part on the selection of the second set of synchronization signal blocks, wherein the synchronization signal block is selected based at least in part on being associated with the first non-serving cell.5.The UE of claim 1, wherein the second set of synchronization signal blocks is associated with a first non-serving cell that has a second physical cell identifier, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:receive a third set of synchronization signal blocks associated with a second non-serving cell that has a third physical cell identifier; andselect the second set of synchronization signal blocks from among the second set of synchronization signal blocks and the third set of synchronization signal blocks, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the selection of the second set of synchronization signal blocks.6.The UE of claim 5, wherein the one or more reference signal received power thresholds comprise a reference signal received power threshold, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:compare the reference signal received power threshold with a reference signal received power metric associated with the first set of synchronization signal blocks, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the comparison.7.The UE of claim 5, wherein the one or more reference signal received power thresholds comprise a reference signal received power threshold associated with the serving cell and the one or more non-serving cells, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:compare the reference signal received power threshold with a reference signal received power metric associated with the first set of synchronization signal blocks or the second set of synchronization signal blocks, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the comparison.8.The UE of claim 5, wherein the one or more reference signal received power thresholds comprise a first reference signal received power threshold associated with the serving cell and a second reference signal received power threshold associated with the first non-serving cell, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:compare the first reference signal received power threshold with a first reference signal received power metric associated with the first set of synchronization signal blocks; andcompare the second reference signal received power threshold with a second reference signal received power metric associated with the second set of synchronization signal blocks, wherein the first set of synchronization signal blocks or the second set of synchronization signal blocks is selected based at least in part on the comparisons.9.The UE of claim 1, wherein the one or more non-serving cells comprises a non-serving cell that has a second physical cell identifier, and wherein the one or more reference signal received power thresholds comprise a first reference signal received power threshold associated with the first physical cell identifier and a second reference signal received power threshold associated with the second physical cell identifier.10.The UE of claim 9, wherein the synchronization signal block is of the first set of synchronization signal blocks, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:determine that a reference signal received power metric associated with the synchronization signal block satisfies the first reference signal received power threshold, wherein the synchronization signal block is selected based at least in part on the determination.11.The UE of claim 9, wherein the synchronization signal block is of the second set of synchronization signal blocks, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:determine that a reference signal received power metric associated with the synchronization signal block satisfies the second reference signal received power threshold, wherein the synchronization signal block is selected based at least in part on the determination.12.A user equipment (UE) , comprising:one or more memories storing processor-executable code; andone or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to:receive a first set of synchronization signal blocks associated with a serving cell that has a first physical cell identifier, the first set of synchronization signal blocks received from a first transmission-reception point;receive a second set of synchronization signal blocks associated with a non-serving cell that has a second physical cell identifier different from the first physical cell identifier, the second set of synchronization signal blocks received from a second transmission-reception point that has reduced downlink capabilities relative to the first transmission-reception point;receive a downlink control information message triggering a random access procedure and indicating one or more of the first physical cell identifier or the second physical cell identifier; andtransmit a random access preamble associated with the random access procedure in a random access resource associated with a synchronization signal block selected from either the first set of synchronization signal blocks or the second set of synchronization signal blocks based at least in part on the downlink control information message.13.The UE of claim 12, wherein the downlink control information message indicates one or more of the first physical cell identifier or the second physical cell identifier via one or more cell indicator fields.14.The UE of claim 12, wherein the downlink control information message indicates the first physical cell identifier and the second physical cell identifier, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between the first physical cell identifier and the second physical cell identifier based at least in part on a reference signal received power threshold.15.The UE of claim 12, wherein the downlink control information message indicates the first physical cell identifier and the second physical cell identifier, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between the first physical cell identifier and the second physical cell identifier based at least in part on a first reference signal received power threshold associated with the first physical cell identifier and based at least in part on a second reference signal received power threshold associated with the second physical cell identifier.16.A user equipment (UE) , comprising:one or more memories storing processor-executable code; andone or more processors coupled with the one or more memories and individually or collectively operable to execute the code to cause the UE to:receive a first set of synchronization signal blocks associated with a serving cell that has a first physical cell identifier, wherein the first set of synchronization signal blocks comprises a first subset of synchronization signal blocks received from a first transmission-reception point and a second subset of synchronization signal blocks received from a second transmission-reception point that has reduced downlink capabilities relative to the first transmission-reception point;receive a second set of synchronization signal blocks associated with a non-serving cell that has a second physical cell identifier, wherein the second set of synchronization signal blocks comprises a third subset of synchronization signal blocks received from a third transmission-reception point and a fourth subset of synchronization signal blocks received from a fourth transmission-reception point that has reduced downlink capabilities relative to the third transmission-reception point; andtransmit a random access preamble in a random access resource associated with a synchronization signal block selected from the first set of synchronization signal blocks or the second set of synchronization signal blocks.17.The UE of claim 16, wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between the first physical cell identifier or the second physical cell identifier, wherein the synchronization signal block is selected from the first set of synchronization signal blocks or the second set of synchronization signal blocks based at least in part on the selection of the first physical cell identifier or the second physical cell identifier.18.The UE of claim 16, wherein the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between a first superset of synchronization signal blocks and a second superset of synchronization signal blocks, wherein the first superset comprises the first subset of synchronization signal blocks and the third subset of synchronization signal blocks, and wherein the second superset comprises the second subset of synchronization signal blocks and the fourth subset of synchronization signal blocks; andselect between the first physical cell identifier or the second physical cell identifier based at least in part on the selection between the first superset and the second superset, wherein the synchronization signal block is selected based at least in part on the selection of the first physical cell identifier or the second physical cell identifier.19.The UE of claim 16, wherein the random access preamble is associated with a random access procedure triggered by downlink control message, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between the first physical cell identifier or the second physical cell identifier based at least in part on the downlink control message comprising an indication of the first physical cell identifier or the second physical cell identifier; andselect, based at least in part on the selection of the first physical cell identifier, between the first subset of synchronization signal blocks and the second subset of synchronization signal blocks based at least in part on one or more reference signal received power thresholds; orselect, based at least in part on the selection of the second physical cell identifier, between the third subset of synchronization signal blocks and the fourth subset of synchronization signal blocks based at least in part on the one or more reference signal received power thresholds.20.The UE of claim 16, wherein the random access preamble is associated with a random access procedure triggered by downlink control message, and the one or more processors are individually or collectively further operable to execute the code to cause the UE to:select between the first physical cell identifier or the second physical cell identifier based at least in part on the downlink control message comprising an indication of the first physical cell identifier or the second physical cell identifier; andselect, based at least in part on the selection of the first physical cell identifier, between the first subset of synchronization signal blocks and the second subset of synchronization signal blocks based at least in part on the downlink control message comprising an indication of the first subset or the second subset; orselect, based at least in part on the selection of the second physical cell identifier, between the third subset of synchronization signal blocks and the fourth subset of synchronization signal blocks based at least in part on the downlink control message comprising an indication of the third subset or the fourth subset.