Devices and methods for layer 1 report retransmission
The retransmission mechanism for L1 reports in 3GPP communication systems addresses the issue of missing reports by enabling UE to store and retransmit L1 properties at the correct transmission occasion, improving prediction accuracy for NEs.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2024-09-27
- Publication Date
- 2026-04-02
AI Technical Summary
In 3GPP communication systems, network entities (NE) face challenges in accurately predicting layer 1 (L1) properties due to missing or undecodable L1 reports from user equipment (UE), leading to incorrect predictions for future slots, as current aperiodic L1 reports are based on the latest transmission occasion rather than the expected earlier transmission occasion.
A retransmission mechanism is implemented for L1 reports, where the NE indicates whether a report is for initial or retransmission and specifies the desired transmission occasion, allowing the UE to store reports in a buffer and retransmit missing L1 reports using control signals or higher layer signaling to ensure accurate reporting.
This mechanism ensures that NEs receive L1 reports corresponding to the intended transmission occasion, enhancing the accuracy of L1 property predictions and mitigating the impact of report loss.
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Figure CN2024121786_02042026_PF_FP_ABST
Abstract
Description
DEVICES AND METHODS FOR LAYER 1 REPORT RETRANSMISSION
[0001] FIELD OF THE DISCLOSURE
[0002] This document generally describes methods and devices operating in wireless communication systems such as (but not limited to) the ones described in 5G standard documents, known as 3rd Generation Partnership Project (3GPP) communication systems.BACKGROUND
[0003] This background description is provided for the purpose of generally presenting the context of the disclosure and the technical problems. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure.
[0004] A network entity (NE) , which is a part of a 3GGP communication system, may configure a user equipment (UE) to measure some layer 1 (L1) properties and provide them to the NE into an L1 report, as uplink control information (UCI) , by physical uplink shared channel (PUSCH) or physical uplink control channel (PUCCH) . The NE may configure the UE to transmit the L1 report aperiodically, semi-persistently, periodically, or based on a UE detected event. In one example, the NE configures an L1 report via radio resource control (RRC) signaling, e.g., CSI-ReportConfig.
[0005] For the L1 report, the NE may configure one or multiple channel state information reference signal (CSI-RS) resources, one or multiple synchronization signal block (SSB) resources, and / or one or multiple sounding reference signal (SRS) resources as channel measurement resource (CMR) for the UE to measure the properties of the downlink channel. The NE may further configure one or multiple CSI-RS resources, one or multiple channel state information interference measurement (CSI-IM) resources, and / or one or multiple SRS resources as interference measurement resource (IMR) for UE to measure interference.
[0006] For the L1 report, the NE may configure one or more report quantities, which may include one or more of the following: SSB resource indicator (SSBRI) , CSI-RS resource indicator (CRI) , rank indicator (RI) , precoder matrix indicator (PMI) , channel quality indicator (CQI) , layer indicator (LI) , time-domain channel property (TDCP) , delay offset (DO) , frequency offset (FO) , phase offset (PO) , layer 1 reference signal received power (L1-RSRP) , layer 1 signal-to-interference plus noise ratio (L1-SINR) , or received signal strength indication (RSSI) . The SSBRI is used to indicate one of the configured SSB resources for the CSI report. The CRI is used to indicate one of the configured CSI-RS resources for the CSI report. RI and PMI are used to indicate the digital precoder, CQI is used to indicate the signal-to-interference plus noise (SINR) status in order to assist the NE to determine the modulation and coding scheme (MCS) , and LI is used to identify the strongest layer for the reported precoder indicated by RI and PMI. TDCP is used to indicate the cross-correlation for channel in different time-domains, which can reflect the channel variance speed. DO is used to indicate the delay difference between two CSI-RS resource sets, e.g., two transmission and reception points (TRPs) . FO is used to indicate the frequency difference between two CSI-RS resource sets, e.g., two TRPs. PO is used to indicate the uplink and downlink channel phase difference between two CSI-RS resources, e.g., two TRPs. L1-RSRP is used to indicate the signal quality for each resource element (RE) . L1-SINR is used to indicate the SINR for each RE. RSSI is used to indicate the interference strength. For each report quantity, the NE may configure the UE to report one or multiple values based on different CMRs / IMRs. Details on the report quantity are defined in 3GPP technical specification (TS) 38.214.
[0007] To facilitate various operations on the NE side, the UE may be configured to measure and report some L1 properties based on a certain transmission occasion (TO) of the CMR. However, if the NE fails to decode one or multiple of the L1 reports, or the UE fails to transmit one or multiple of the L1 reports due to a UCI collision, CSI omission, CSI processing unit (CPU) limits, processing delay limits, or other causes, the NE may not be able to correctly predict the L1 property for future slots.
[0008] To mitigate the impact of L1 report loss, the NE may trigger an aperiodic L1 report, after it detects that one L1 report is lost (for any reason) . However, currently, for the aperiodic L1 report, the UE needs to calculate the L1 properties based on the latest TO of the CMR, which is different from a prior TO of the CMR for which the NE expects to receive the (missing) report.
[0009] Thus, currently, the UE sends the L1 report as a substitute for the missing L1 report , but the two reports are not equivalent or do not provide the same information as they correspond to different TOs. As such, the UE provides to the NE the L1 properties associated with the latest TO instead of an earlier TO for which the NE is expecting.SUMMARY
[0010] To retrieve missing L1 reports that include L1 properties associated with a past TO, the NE implements a retransmission mechanism that uses a control signal for enabling the UE to retransmit the missing L1 reports. The NE indicates whether an L1 report is for an initial transmission or a retransmission. If the L1 report is for retransmission, the NE indicates the TO for which the L1 report is expected to be retransmitted. In one embodiment, the NE configures a first L1 report configuration for an initial transmission and a second L1 report configuration for a retransmission. The NE indicates the TO for which the UE to retransmit the first L1 report. In one embodiment, the UE may use any of plural candidate UL resources for retransmitting the L1 report, thus avoiding collisions with other UL transmissions. In another embodiment, the NE and UE may use higher layer signaling for retransmitting the L1 report. In other embodiments, the L1 report may be transmitted as part of an uplink control information (UCI) .
[0011] The NE may also configure buffer management techniques associated with the UE for storing one or more L1 reports that have been sent. The UE removes an L1 report from the buffer when a next L1 report is transmitted, or when receiving an indication that such L1 report has been received by the NE, or when a number of L1 reports stored in the buffer exceeds a maximum value. In one embodiment, the UE removes one or more L1 reports stored in the buffer based on a priority level.BRIEF DESCRIPTION OF THE DRAWINGS
[0012] The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate one or more embodiments and, together with the description, explain these embodiments.
[0013] FIG. 1A illustrates a timeline of a scenario in which the NE receives L1 reports corresponding to various TOs of CMR.
[0014] FIG. 1B illustrates a timeline of a scenario in which an L1 report associated with a CMR TO is lost.
[0015] FIG. 2 illustrates a block diagram of a wireless communication system including NE and UE that perform methods according to various embodiments.
[0016] FIG. 3 illustrates a signal diagram in which the NE schedules the UE to retransmit the first L1 report for the first TO, according to an embodiment.
[0017] FIG. 4A illustrates a flow chart of a UE method for retransmitting an L1 report for a specific TO according to an embodiment.
[0018] FIG. 4B illustrates another flow chart of a UE method for retransmitting an L1 report for a specific TO according to an embodiment.
[0019] FIG. 5A illustrates a flow chart of a NE method for instructing the UE to retransmit an L1 report for a specific TO according to an embodiment.
[0020] FIG. 5B illustrates another flow chart of a NE method for instructing the UE to retransmit an L1 report for a specific TO according to an embodiment.
[0021] FIG. 6 illustrates a timeline of a scenario in which the NE sends a DCI indication to the UE for initial transmission or retransmission, according to an embodiment.
[0022] FIG. 7 illustrates a timeline of a scenario in which the NE configures a first L1 report configuration for initial transmission and a second L1 report configuration for retransmission, according to an embodiment.
[0023] FIG. 8 illustrates a timeline of a scenario in which the NE indicates which TO to be used for the L1 report retransmission, according to an embodiment.
[0024] FIG. 9 illustrates a diagram of a scenario in which the NE configures plural resources for L1 report transmission, according to an embodiment.
[0025] FIG. 10 illustrates a timeline of a scenario in which higher layer signaling is used for retransmission of the L1 report, according to an embodiment.
[0026] FIG. 11 illustrates a timeline of a scenario in which uplink control information (UCI) is used for retransmission of the L1 report according to an embodiment.
[0027] FIG. 12 illustrates an example of buffer management based on a timer or event according to an embodiment.
[0028] FIG. 13 illustrates a flow chart of a UE method for L1 report buffer management based on a timer according to an embodiment.
[0029] FIG. 14 illustrates an example of buffer management based on NE indication according to an embodiment.
[0030] FIG. 15 illustrates a flow chart of a UE method for L1 report buffer management based on NE indication according to an embodiment.
[0031] FIG. 16 illustrates an example of buffer size management based on a priority level according to an embodiment.
[0032] FIG. 17 illustrates a flow chart of a UE method for L1 report buffer management based on report priority according to an embodiment.DETAILED DESCRIPTION
[0033] Methods and devices described in this section embody techniques related to enabling a retransmission mechanism for L1 reports generated and transmitted by the UE so that the NE is able to require and receive the retransmission of an L1 report for a desired TO (i.e., a TO prior to a latest TO, also called “past TO” in this document) . These techniques may configure the UE to initiate a buffer for storing one or more of the transmitted L1 reports so that when a specific L1 report needs to be retransmitted, the UE is capable of selecting that specific report from the buffer and retransmitting it to the NE. The NE and / or UE are also configured to use buffer management techniques for ensuring that desired L1 reports are stored for a certain time and other reports are removed from the buffer. The embodiment descriptions in this section refer to the accompanying drawings. The same reference numbers in different drawings identify the same or similar elements. The detailed descriptions do not preclude other embodiments within the scope of the appended claims. The embodiments are not limited to the described configurations but may be extended to other arrangements.
[0034] As mentioned earlier, there are situations when the NE makes predictions based on L1 reports from the UE but some of these reports might not be received by the NE or the NE cannot decode them. For example, as shown in FIG. 1A, the NE may perform some L1 property prediction 100 (e.g., CSI prediction, beam prediction, or L1-RSRP prediction) , based on the historical L1 properties reported 102 by the UE. The NE may then generate 104 these property predictions at various slots, as illustrated in FIG. 1A. The L1 property measurement takes place during a measuring window 103 while the L1 property prediction transmission takes place during a transmission window 105. However, if the NE fails to decode one or multiple of the L1 reports 106, or the UE fails to transmit one or multiple of the L1 reports 106 due to a UCI collision, CSI omission, CSI processing unit (CPU) limits, processing delay limits, or other causes, the NE may not be able to correctly predict the L1 property for future slots 104.
[0035] To mitigate the impact of L1 report loss, the NE may trigger 128 an aperiodic L1 report, as illustrated in FIG. 1B, after it detects that one L1 report 126 is lost (for any reason) . FIG. 1B shows plural TOs of CMRs 122A, 122B, and 122C that are used by the UE to measure the L1 properties. The figure also shows the transmitted reports 124A, 126, and 124C. However, currently, for the aperiodic L1 report 124C, the UE needs to calculate the L1 properties based on the latest TO 122C of the CMR, which is different from a prior TO 122B of the CMR for which the NE expects to receive the (missing) report 126.
[0036] Thus, currently, the UE sends the L1 report 124C as a substitute for the missing L1 report 126, as indicated by arrow 127, but the two reports are not equivalent or do not provide the same information as they correspond to different TOs 112B 122B and 122C. As such, the UE provides to the NE the L1 properties associated with the latest TO instead of an earlier TO for which the NE is expecting.
[0037] Prior to discussing a retransmission mechanism and associated buffer management techniques for L1 reporting (that overcome the above noted limitations of the existing 5G systems) , a wireless communication system 200 is introduced, as illustrated in FIG. 2. The wireless communication system 200 includes a UE 210 and a NE 220 (only one of each is shown for simplicity, but one skilled in the art would understand that many such elements may be present) communicating wirelessly through a wireless communication channel 201.
[0038] UE 210 may be any user computing device, for example, a smartphone. UE includes antennas connected to an RF front end 211, and a transceiver. The transceiver may be an LTE transceiver 212, a 5G NR transceiver 213, or another transceiver. Although FIG. 2 shows two transceivers being present in the UE 210, one skilled in the art would understand that, while at least one transceiver is present, more than one transceiver being present is optional. The antennas and RF front end 211 can be tuned to one or more frequency bands (e.g., subcarriers) , for example, as defined by 3GPP long term evolution (LTE) , 5G new radio (NR) , and 6G communication standards and implemented by respective transceivers. UE 210 also includes one or more precoders 214, one or more processor (s) 215, and computer-readable storage media (CRSM) 216. Processor (s) 215 may be single or multiple-core processors, and CRSM 216 includes any suitable memory / storage other than propagating signals. For example, memory / storage can include random access memory (RAM) , static RAM (SRAM) , dynamic RAM (DRAM) , non-volatile RAM (NVRAM) , read-only memory (ROM) , and / or flash memory. CRSM 216 stores device data 217 necessary for UE’s communications. The CRSM 216 may also include an L1 configuration manager 218.
[0039] The L1 configuration manager 218 is configured to implement the L1 measurement and reporting techniques. The L1 configuration manager 218 is either preconfigured to implement the L1 reporting, or uses a set of rules or, based on prior communications with the NE, determines which L1 reporting to implement. The UE may also include a buffer 219, which may be managed by the NE, the L1 configuration manager 218 of the UE, or both. The buffer 219 is configured to store one or more L1 reports transmitted by the UE to the NE.
[0040] NE 220 may be any element of a base station (BS) or radio access network (RAN) or core network (CN) or a combination of them. NE 220 and UE 210 may include additional functions and interfaces omitted from the figure in the interest of brevity. Signaling channel 201 generally represents both uplink signals (from the UE to the NE) and downlink signals (from the NE to the UE) .
[0041] NE 220 may provide the functionality of a next generation node B (gNB, e.g., a 5G or 6G base station) or perform various other CN functions. NE 220’s functionality may be distributed across multiple entities (e.g., a central unit, CU, a distributed unit, DU, and a radio unit, RU (not shown) if the NE is the BS) . When NE 220 is the BS, it includes one or more antennas, an RF front end 221 and a transceiver 222 for communicating with UE 210 and other UEs and NEs. NE 220’s antennas and RF front end 221 can be tuned to one or more frequency bands (e.g., subcarriers) , for example as defined by 3GPP LTE, 5G NR, and 6G communication standards and implemented by transceiver 222.
[0042] NE 220 further includes processor (s) 223 and computer-readable storage media (CRSM) 224. Processor (s) 223 can include single or multiple-core processors, and CRSM 224 includes any suitable memory / storage except propagating signals. For example, memory / storage can include RAM, SRAM, DRAM, NVRAM, ROM, and / or flash memory. CRSM 224 stores device data 225, which includes network scheduling data, radio resource management data, applications, and / or an operating system, which are executable by processor (s) 223 to enable wireless communication 201 with UE 210 as well as with other NEs and UEs. CRSM 224 also stores an L1 configuration manager 226. L1 configuration manager 226 causes UE 210 to configure the L1 report based on various factors, which are discussed later, and also to initiate the retransmission of a missing L1 report.
[0043] The retransmission mechanism for L1 reporting is now discussed with regard to methods illustrated in FIGs. 3 to 5B. FIG. 3 is a signal diagram of a method 300 for configuring the UE for the retransmission of a previously transmitted L1 report. The method optionally includes the UE 210 reporting to the NE 220 the UE’s capabilities indicating the supported configurations for the retransmission of the L1 report. Note that any steps that are optional are indicated in the figures with a dash line. The UE may report 302 at least one of the following UE capabilities: supporting of L1 report retransmission; supported types of L1 report configuration (e.g., supported report quantity) for L1 report retransmission; supported maximum number of instances of L1 report for retransmission; supported maximum number of L1 report configurations per component carrier (CC) or across CCs in a band or band combination for L1 report retransmission; supported maximum duration of a timer for the L1 report buffer management; maximum / minimum memory for L1 report retransmission; and / or maximum number of processes per CC or across CCs in a band or band combination for UCI retransmission. Other UE capabilities may be reported.
[0044] In some embodiments, the UE capabilities may be pre-defined in the specification of the communication system without capability signaling reporting to the NE. For example, for a UE (that supports a certain NE-side L1 property prediction) , it is mandatory to support the L1 report storage and / or retransmission.
[0045] Based on the received / predefined UE capabilities, the NE transmits 304 a control signaling to the UE configuring at least a first L1 report configuration with a retransmission indication being enabled. For the retransmission mechanism discussed in these embodiments, the UE needs to know whether the L1 report may need to be retransmitted or not. This need is satisfied by the retransmission indication being enabled. When the UE determines that the retransmission indication is enabled, the UE prepares a corresponding buffer for storing one or more L1 reports, so that they can be retransmitted if the NE requests so. In one embodiment, the NE may configure two L1 report configurations, a first L1 report configuration with retransmission indication enabled, so that the UE knows to prepare the buffer for storing the L1 reports corresponding to the first L1 report configuration, and a legacy L1 report configuration with retransmission indication disabled, i.e., the UE does not prepare any buffer for storing an L1 report corresponding to the legacy L1 report configuration.
[0046] In one embodiment, the retransmission indication used to enable / disable the buffer for storing the L1 report may be an RRC parameter in a CSI-ReportConfig such as enableRetransmission. If the RRC parameter is not configured, the retransmission is disabled. In a variation of this embodiment, a granularity of the retransmission indication may be made more general, e.g., the L1 report configuration may be provided per CSI report configuration, per type of CSI report configuration (e.g., CSI report for NE side prediction or CSI report based on a certain report quantity) , per bandwidth part, per serving cell, or per serving cell group.
[0047] The control signaling in step 304 may also configure at least one of the following features, which are associated with the first L1 report configuration: a second L1 report configuration for retransmission that is linked to the first L1 report configuration, whether the L1 report is based on UCI or higher layer signaling; a timer for buffer management; or enabling an indication of acknowledgement of the L1 report. In one embodiment, the NE may configure a third L1 report configuration without retransmission (i.e., the legacy L1 reporting discussed above) .
[0048] The NE may configure the first L1 report configuration based on a CSI report configuration, e.g., CSI-ReportConfig. In the first L1 report configuration, the NE configures a list of CMR (s) , and also configures the report quantity to include at least one of the following parameters: SSBRI, CRI, RI, PMI, CQI, LI, TDCP, DO, FO, PO, L1-RSRP, L1-SINR, or RSSI. The NE may further configure at least one of the following: one or multiple uplink resources for the L1 report; at least one IMR for interference measurement; time restriction for channel measurement; time restriction for interference measurement; and / or configuration to identify the TO (s) of CMR for the L1 report. The NE may transmit the control signaling in step 304 by RRC signaling, e.g., RRCReconfiguration.
[0049] The NE may provide some of the configurations or update some of the configurations by medium access control (MAC) control element (CE) , e.g., MAC CE activating the (semi-persistent) L1 report, or downlink control information (DCI) , e.g., different triggering states for the DCI triggering the (aperiodic) L1 report may correspond to different configurations. The NE optionally transmits 306 the MAC CE or DCI activating or triggering a first L1 report for the first L1 report configuration.
[0050] After receiving 308 reference signals on configured CMR (s) at TO for the first L1 report configuration, the UE measures at least an L1 property and then the UE optionally transmits 310 (note that sometimes, the UE may fail to transmit the corresponding L1 report, which results in the lost report at the NE side) the first L1 report including the at least L1 property. In case that the NE fails to receive the first L1 report (for example, for the reasons previously discussed above) , the NE sends 312 to the UE a scheduling message for scheduling a retransmission of the first L1 report or scheduling a second L1 report retransmitting part or all of the first L1 report, where the second L1 report is based on the second L1 report configuration that is linked to the first L1 report configuration. The scheduling message may be a DCI message. Then the UE determines the buffer status for the L1 report retransmission. If the buffer stores the first L1 report, the UE retransmits 314 the first L1 report; otherwise, the UE drops the retransmission of the first L1 report or transmits an indication to the NE signaling that the buffer for the first L1 report is empty (i.e., flushed) .
[0051] FIGs. 4A and 4B illustrate the UE behavior for the retransmission of the L1 report according to different embodiments. FIG. 4A is a flow chart of a method 400A that includes an optional step 402 of transmitting the UE capabilities on supported configurations (or features) for L1 report retransmission and also a buffer size for L1 report buffer management. This step is similar to step 302. The UE receives 404 a control signal from the NE, similar to step 304, for configuring the first L1 report configuration. As previously discussed, for an initial transmission, the first L1 report configuration does not have the retransmission indicator enabled, i.e., no buffer is initiated for storing the L1 report and the UE does not try to store the L1 report after being transmitted to the NE. However, if the retransmission indicator is enabled in the first L1 report configuration, the UE prepares the buffer and stores the L1 report after or just before being transmitted to the NE. In some aspects, the UE may store the L1 report after generating the L1 report. The control signal may also configure the UE in step 404 to have a second L1 report configuration, linked to the first L1 report configuration. In one embodiment, the first L1 report configuration is for an initial transmission of the L1 report and the second L1 report configuration is for a retransmission of the L1 report. The two L1 report configurations may also be used for other scenarios. The signaling for these configurations and / or reports is discussed later. The buffer management for storing the transmitted L1 reports is also discussed later.
[0052] The UE optionally receives 406 a message, for example, MAC CE or DCI, that activates or triggers the first L1 report configuration, followed by receiving 408 the TO on CMR, where the CMR is configured in a CSI report configuration. Based on the latest TO for the CMR, the UE measures and transmits 410 the first L1 report to the NE. If the NE determines that the L1 report needs to be retransmitted, the UE receives 412 a scheduling message, from the NE, scheduling the retransmission of the first L1 report. In one embodiment, when only the first L1 report configuration is used, the scheduling message configures the UE to use the first L1 report configuration for retransmitting the first L1 report. If the UE is configured with both the first and second L1 report configurations, then the scheduling message configures the UE to use the second L1 report configuration for the retransmission of the L1 report.
[0053] The UE determines 414 whether the buffer was initialized. If the buffer was not initialized, indicated by “NO” in the figure, then the UE drops 415 the retransmission of the first L1 report as the report is not available and the TO of the first L1 report is past, i.e., the UE cannot measure again the L1 parameters reported in the first L1 report for the specific conditions of the past TO. If the buffer was initialized, indicated by “YES” in the figure, then the UE determines 416 whether the buffer stores the already transmitted first L1 report. If the buffer is not storing the transmitted first L1 report, indicated by “NO” in the figure, then the UE drops 415 the retransmission as the first L1 report is not available and the TO of the first L1 report is past, i.e., the UE cannot measure again the L1 parameters reported in the first L1 report for the specific conditions of the TO. However, if the result of the determination 416 is that the buffer is initialized and the first L1 report is stored in the buffer, indicated by “YES” in the figure, the UE retransmits 418 the first L1 report stored in the buffer.
[0054] FIG. 4B is a flow chart of a UE method 400B similar to method 400A, except that steps 402, 406, 408, and 410 are excluded. Method 400B indicates that not all the steps shown in method 400A need to be performed for a retransmission of the first L1 report to take place. However, the method 400B does not exclude the presence of one or more of the steps 402, 406, 408, and 410 from method 400A. For example, in one embodiment, method 400B may also include step 408. In a different embodiment, method 400B may include additional steps 406 and 408. In yet another embodiment, the method 400B may include additional steps 406, 408, and 410. One skilled in the art would understand that any number of these steps from method 400A may be added to the method 400B.
[0055] FIG. 5A illustrates the NE behavior for the retransmission of the first L1 report discussed with regard to FIG. 3. The description of the steps that are similar or identical to those of methods 300 to 400B are omitted. In method 500A, the NE optionally receives 502 the UE capability with regard to the supported L1 report configuration, similar to steps 302 and 402 (note that step 502 is performed by the NE and step 402 is performed by the UE, and the actions described by these steps mirror each other; the same is true for other similar steps described with regard to the figures) . The NE transmits 504 the control signaling discussed above with regard to steps 304 and 404. The NE optionally transmits 506 the message (e.g., MAC CE or DCI) activating or triggering the first L1 report configuration, similar to steps 306 and 406, and transmits 508 the CMR based on which the UE needs to perform L1 measurements. The CMR is configured in CSI report configuration. The NE optionally receives 510 the first L1 report, similar to steps 310 and 410. Note that under certain circumstances, e.g., the UE fails to send the L1 report, the NE does not receive the L1 report. When the NE fails to receive the first L1 report or fails to decode this expected report, the NE transmits 512 a scheduling message to the UE for scheduling the retransmission of the first L1 report, similar to steps 312 and 412. The NE then receives 518 the retransmission of the first L1 report.
[0056] FIG. 5B is a flow chart of an NE method 500B, which is similar to the method 500A. Similar to method 400B, method 500B may include less steps than the method 500A. However, any of the steps or combination of these steps present in the method 500A and not currently shown in the method 500B may be added to the method 500B.
[0057] In this document, unless specified, an RRC signaling may indicate an RRC reconfiguration message from NE to UE, or a System Information Block (SIB) , where the SIB can be an existing SIB (e.g., SIB1) or a newly added SIB (e.g., SIB J, where J is an integer above 21) transmitted by the gNB. In some embodiments, the NE may receive the UE capability from a UE or from a CN (e.g., Access and Mobility Management Function (AMF) ) or another NE.
[0058] The methods illustrated in FIGs. 3 to 5B may be modified as discussed with regard to FIGs. 6 to 17, which illustrate timeline events. In an embodiment, the NE may indicate whether a triggered L1 report is for initial transmission or retransmission. The NE may provide the retransmission indication via a message, e.g., PDCCH carrying a DCI triggering 628 the L1 report, as illustrated in FIG. 6. This figure shows various TOs of CMRs (622A to 622C) being sent by the NE to the UE. In response to these TOs, the UE measures L1 properties and reports the measurements with corresponding L1 reports 624A. However, for a given TO 622B, the corresponding L1 report 626 is lost or undecodable. Thus, the NE sends 628 a scheduling message (e.g., PDCCH scheduling for aperiodic L1 report for retransmission) to the UE to retransmit the lost L1 report. Although the UE receives a most recent TO 622C of CMR after receiving the retransmission request 628, the scheduling message instructs the UE to send the L1 report corresponding to the prior TO 622B, i.e., corresponding to lost L1 report 626. The UE then retransmits the lost report as L1 report 624B (which is indicated by arrow 627 as corresponding lost report 626) stored in the buffer, and later sends the corresponding L1 report (not shown) for the latest TO 622C.
[0059] In some embodiments, for L1 report retransmission, the NE and UE may determine whether the report 624B is a retransmission, corresponding to the most recent TO 622C or multiple TOs, of an L1 report (1) configured or (2) scheduled to be transmitted or (3) transmitted X symbols before the first symbol of the PDCCH (s) 628 with the DCI message. The value of X may be pre-defined, e.g., X=0, or configured by the NE via RRC signaling, MAC CE, or DCI (e.g., the same DCI triggering the L1 report) , or reported by the UE. In other words, the scheduling message 628 may specify the value of X so that the L1 report corresponding to the TO 622B is retransmitted (if stored in a buffer) , although a more recent TO 622C exists.
[0060] In some other embodiments, for L1 report transmission, the NE may further indicate the information about the one or multiple TOs 622B of the previous L1 report for retransmission. In some embodiments, the NE further configures or indicates the number of TOs for retransmission for an L1 report (i.e., an L1 report does not have to be associated with a single TO, the L1 report may be associated with plural TOs) . The UE may retransmit the L1 report for one or multiple TOs.
[0061] In some embodiments, the initial transmission 626 and the retransmission 624 of the L1 report may be in the same serving cell or uplink bandwidth part (BWP) . In some other embodiments, the initial transmission and the retransmission of the L1 report may be in different serving cells or different uplink BWPs. For these cases, the NE may further indicate the serving cell index and / or BWP index for the corresponding initial transmission and / or retransmission of the L1 report.
[0062] In some embodiments, the NE may provide a status indication (or transmission indication) , which has a first value for the initial transmission and a second value, different from the first value, for the retransmission of the L1 report. The status indication may be provided by a dedicated DCI field in the scheduling message. Thus, the dedicated DCI field may indicate whether the triggered L1 report is based on initial transmission or retransmission.
[0063] In some other embodiments, the NE may provide the status indication of the initial transmission or retransmission by indicating different aperiodic triggering states, where different triggering states may correspond to initial transmission or retransmission of the L1 report. In one example, the NE indicates the triggering states using the DCI field CSI request.
[0064] In some other embodiments, the NE and UE may determine whether the triggered L1 report is for initial transmission or retransmission based on the configuration of the L1 report, e.g., time-domain behavior of the L1 report. In one example, if the NE configures the time-domain behavior for the triggered aperiodic L1 report as periodic or semi-persistent, the NE and UE may determine that the triggered aperiodic L1 report is for retransmission; otherwise, the NE and UE may determine that the triggered aperiodic L1 report is for initial transmission.
[0065] FIG. 7 illustrates a case 700 in which the retransmission of an L1 report is based on a second L1 report configuration 704, which is linked to a first L1 report configuration 702. The first L1 report configuration 702 is for an initial transmission of the L1 report while the second L1 report configuration 704 is for the retransmission of the L1 report. In one embodiment, the first L1 report configuration is different from the second L1 report configuration. Then, when the NE triggers the first L1 report, the UE performs initial transmission, using the first L1 report configuration 702. When the NE triggers 728 the retransmission of the lost L1 report 726, the UE performs retransmission 724B of the L1 report for the indicated TO 622B, as illustrated in FIG. 7.
[0066] In some embodiments, for the retransmitted L1 report 724B, the NE and UE may determine if the report is a retransmission of the first L1 report 726, corresponding to the TO 622B or multiple TOs, and the first L1 report 726 is (1) configured or (2) scheduled to be transmitted, or (3) transmitted X symbols before the first symbol of the PDCCH (s) 728 with the DCI message. The value of X may be pre-defined, e.g., X=0, or configured by the NE via RRC signaling, MAC CE, or DCI (e.g., the same DCI triggering the L1 report) , or reported by the UE. In some other embodiments, for the second L1 report 724B, the NE may further indicate the information about the TO 622B, of the first L1 report 726, for retransmission. In some embodiments, the NE may further configure or indicate a number of TOs for retransmission for an L1 report. The UE may retransmit a previous L1 report for one or multiple TOs.
[0067] In some embodiments, the initial transmission and the retransmission of the L1 report may be in the same serving cell or BWP. Thus, the NE may configure the first L1 report configuration 702 and the second linked L1 report configuration 704 in the same serving cell or BWP or may configure uplink resources for the L1 report in the same serving cell or BWP. In some other embodiments, the initial transmission and the retransmission of the L1 report may be in different serving cells or different uplink BWPs. Then the NE may configure the first and second linked L1 report configurations in different serving cells or BWPs or may configure the uplink resources for the L1 report in the different serving cells or BWPs.
[0068] In some embodiments, the NE may configure whether an L1 report configuration linked to another L1 report configuration is for initial transmission or retransmission by an RRC parameter associated with or configured in the L1 report configuration.
[0069] In some other embodiments, the NE and UE determines whether an L1 report configuration linked to another L1 report configuration is for initial transmission or retransmission based on the configuration of the L1 report configuration, e.g., time-domain behavior of the L1 report, the CMR configuration, report quantity configuration, and so on. In one example, if the NE configures the time-domain behavior for the L1 report configuration as periodic or semi-persistent, the NE and UE may determine the L1 report configuration is for initial transmission; otherwise (e.g., if the time-domain behavior for the L1 report configuration is aperiodic) , the NE and UE may determine the triggered L1 report is for retransmission. In another example, if the CMR is configured in the L1 report configuration, the NE and UE may determine the L1 report configuration is for initial transmission; otherwise, the NE and UE may determine the L1 report configuration is for retransmission. In another example, if the report quantity is configured in the L1 report configuration, the NE and UE may determine the L1 report configuration is for initial transmission; otherwise, the NE and UE may determine the L1 report configuration is for retransmission.
[0070] FIG. 8 illustrates an embodiment 800 in which the NE may indicate or configure the TO of the CMR for an L1 report. Then, for an initial transmission 624A, the NE may indicate or configure the UE to perform the L1 report based on the latest TO 622A of the CMR, e.g., latest TO of the CMR before the CSI reference resource defined in 3GPP TS 38.214. For retransmission, the NE may indicate or configure the UE to transmit the L1 report 824B based on one or multiple TOs 622B received prior to the latest TO 622C of the CMR, as shown in FIG 8. The initial L1 report 826 for TO 622B is lost in this embodiment and the NE informs the UE about the retransmission based on a scheduling message 828.
[0071] In some embodiments, for the aperiodic L1 report 824B, the NE and UE may determine the corresponding TO (s) 622B of CMR being X symbols before the first symbol of the PDCCH (s) 828 with the DCI message or before the CSI reference resource that should be used for the L1 measurement, where X may be indicated by the NE. The NE may indicate the value of X by the DCI scheduling 828 the aperiodic L1 report 824B. In one example, the NE explicitly indicates the value of X by a DCI field. In another example, the NE indicates the value of X by indicating different aperiodic CSI triggering states, where the NE may configure by RRC signaling a different value of X corresponding to different aperiodic CSI triggering states. The NE may further indicate the number of TOs of the CMR for the L1 measurement.
[0072] In some other embodiments, for an aperiodic L1 report, the NE may indicate the time-domain location of the CSI reference resource. The NE may provide such indication by the DCI scheduling the aperiodic L1 report. Then, the NE and UE may determine the TO (s) of the CMR before the indicated CSI reference resource should be used for the L1 measurement. The NE may further indicate the number of TOs of the CMR for the L1 measurement.
[0073] In some other embodiments, for the aperiodic L1 report, the NE may indicate the time-domain location, e.g., slot (s) , of the TO (s) of the CMR for the L1 measurement. The NE may provide such indication by the DCI scheduling 828 the aperiodic L1 report.
[0074] FIG. 9 shows an embodiment 900 in which the NE may configure or schedule multiple TOs 930, 932 of an uplink channel or multiple resources of an uplink channel for L1 reporting. In one example, the NE may configure or schedule multiple TOs of PUSCH or multiple PUCCH resources for the L1 report. The UE may transmit the L1 report on a subset of TOs or resources of the uplink channel. In one example, the UE may transmit the L1 report on the TO (s) 932 or resource (s) available for the L1 report, e.g., without collision with other UL channel resources 934. The UE may refrain from transmitting the L1 report, e.g., dropping of the L1 report, on the TO (s) 930 or resource (s) that overlap in the time domain with other UL channel resources 934.
[0075] In some embodiments, the NE may further configure at least one threshold for the UE to determine the number of TOs or repetitions for the L1 report. In one example, the NE may configure a threshold for 2 repetitions. If the measured downlink quality, e.g., L1-RSRP or higher layer filtered, for a downlink signal, e.g., SSB / CSI-RS, that is associated with the uplink channel, e.g., configured as spatial relation source or pathloss reference signal, is below or equal to the threshold, the UE may transmit the L1 report by 2 repetitions; otherwise, the UE may transmit the L1 report by 1 repetition. In another example, the NE may configure multiple thresholds for different number of repetitions, and the UE can determine the number of repetitions based on the thresholds and the downlink measurement results.
[0076] In some other embodiments, the NE may dynamically indicate the number of TOs or repetitions for the L1 report by MAC CE, e.g., MAC CE activating the L1 report, or DCI, e.g., DCI scheduling the aperiodic L1 report.
[0077] FIG. 10 illustrates an embodiment 1000 in which the NE may configure or schedule the UE to transmit the missing L1 report 1026 based on higher layer signaling, e.g., MAC CE or RRC 1028. Then the NE may schedule 1028 a retransmission of the PUSCH with the higher layer signaling if it fails to decode it, as shown in FIG. 10. In other words, the UE sends the retransmission 1024B based on higher layer signaling in this embodiment.
[0078] In some embodiments, for a L1 report configuration, the NE may configure whether it should be reported by L1 signaling, e.g., UCI on PUCCH or PUSCH, or by higher layer signaling, e.g., MAC CE or RRC. The NE may provide the configuration by RRC signaling, MAC CE (e.g., MAC CE activating the L1 report) , or DCI (e.g., DCI scheduling the L1 report) . In one example, the NE may configure the UE to transmit the L1 report with retransmission enabled by higher layer signaling 1028, e.g., MAC CE or RRC, and configure the UE to transmit the L1 report with retransmission disabled by UCI.
[0079] FIG. 11 illustrates an embodiment 1100 in which the NE may configure one or multiple transmission processes for UCI transmission 1124A, 1124B for a BWP or serving cell. Thus, when one UCI 1126 including an L1 report is lost, another UCI 1124B is used for L1 report retransmission. For one UCI, the NE may configure or indicate a transmission process ID. The NE may further configure or indicate whether a triggered transmission is for an initial transmission or retransmission of a UCI on a UCI process 1128 as shown in FIG. 11.
[0080] In some embodiments, for a PUCCH or PUSCH resource with UCI 1124A, 1124B, the NE may configure a UCI process ID. Then for a retransmission for a UCI process, the UE retransmits the whole UCI in the same process.
[0081] In some other embodiments, for an L1 report configuration, the NE may configure a UCI process ID. Then, when multiple L1 reports overlap in time domain, the UE may drop at least one of the L1 reports or transmit all the L1 reports. The UE may determine whether to drop at least one of the L1 reports or transmit all the L1 reports based on whether the L1 reports correspond to the L1 report configurations with the same UCI process ID. In one example, if the L1 reports correspond to the L1 report configurations with the same UCI process ID, the UE may transmit all the L1 reports if the maximum payload size for the UCI on PUCCH or PUSCH is sufficient to carry all the L1 reports; otherwise, the UE may transmit one or a subset of L1 reports that share the same UCI process ID and drop at least one of the L1 reports with different UCI process ID.
[0082] In an embodiment, when a first uplink channel with retransmitted L1 report or retransmitted UCI overlaps with a second uplink channel with other UCI, e.g., initial transmission of L1 report, hybrid automatic repeat request-acknowledgement (HARQ-ACK) information, scheduling request (SR) , unused transmission occasion (UTO) , the UE may perform at least one of the followings:
[0083] · Drop the first uplink channel, and only transmit the other UCI on the first uplink channel;
[0084] · Drop the second uplink channel, and transmit the retransmitted L1 report or retransmitted UCI on the first uplink channel; or
[0085] · Multiplex the retransmitted L1 report or retransmitted UCI and other UCI, and transmit the multiplexed UCI on the first or second uplink channel.
[0086] In some embodiments, the UE may report the UE capability indicating the supported UE behaviors noted above. In some other embodiments, the NE may configure the UE behavior based on one of the above factors.
[0087] In some embodiments, the UE may determine the priority for the UCI / CSI dropping or multiplexing based on at least one of the following:
[0088] · Serving cell for the CMR or L1 report, e.g., higher priority for the smaller serving cell index;
[0089] · Time-domain behavior for the report type (aperiodic, semi-persistent, periodic, or event-triggered) , e.g., the order of the priority may be: (event-triggered > aperiodic > semi-persistent > periodic) ;
[0090] · Report quantity, e.g., the order of the priority may be: L1-RSRP / L1-SINR > L1 report other than L1-RSRP / L1-SINR;
[0091] · L1 report configuration ID, e.g., higher priority for the smaller L1 report configuration ID;
[0092] · Whether the L1 report is for initial transmission or retransmission or number of retransmissions, e.g., higher priority for retransmission compared to initial transmission, or higher priority for L1 report with greater number of retransmissions; or
[0093] · Content for the UCI, e.g., HARQ-ACK > L1 report.
[0094] Those skilled in the art would understand that other criteria may be used for the priority order, for example, the priority order for content of UCI, like L1 report > HARQ-ACK.
[0095] While FIGs. 6 to 11 presented variations for the retransmission mechanism, the following figures describe buffer management procedures associated with the buffer 219 at the UE (see FIG. 2) . FIG. 12 illustrates an embodiment 1200 in which an L1 report configuration is enabled (the retransmission indication is enabled) for retransmission. The NE and / or the UE, in response to the retransmission indication being enabled, configures a timer for the UE to determine when to clear the buffer 219. The UE may start at time 1240 or restart at time 1244 the timer for an L1 report configuration when or after the UE transmits 624A an initial transmission of an L1 report for a given TO 622A, corresponding to the L1 report configuration. The UE removes (or flushes) at time 1244 the transmitted L1 report 624A from the buffer when the timer expires or is restarted and stores a new L1 report 1226 in the buffer for a new TO 622B. During a period 1242 (which corresponds to the timer length) , the first L1 report 624A is stored in the buffer. When the timer expires at time 1244, the timer resets or restarts and the existing L1 report 624A is removed from the buffer. The UE stores a new L1 report 1226, which happens to be lost, i.e., not received by the NE. The UE keeps the new L1 report 1226 in the buffer until the timer expires at time 1248. If the UE receives an indication from the NE, during the time period 1246, before the timer expires, that the L1 report 1226 is lost, the UE retransmits the L1 report 1226, as previously discussed. However, if no indication is received from the NE until when the timer expires at time 1248, the L1 report 1226 is removed from the buffer. In some embodiments, the UE may store the L1 report in the buffer when / after it transmits an initial transmission of the L1 report. In some other embodiments, the UE may store the L1 report in the buffer after generating the L1 report.
[0096] The UE may flush / clean the buffer for the L1 report and / or stop the timer when at least one of the following events occurs:
[0097] · The timer for the L1 report configuration expires;
[0098] · The L1 report configuration is deactivated;
[0099] · The L1 report retransmission is disabled;
[0100] · The serving cell for the L1 report configuration is deactivated;
[0101] · UE flushes all HARQ buffers for the same serving cell with the L1 report configuration configured;
[0102] · When the UE receives the L1 report configuration for retransmission of a second L1 report, for which the TO index is larger than the current one in the buffer (e.g., newer TO than current one) ; or
[0103] · When the UE detects that the prediction window correlated with the L1 report is started.
[0104] The UE may reset the timer for a L1 report configuration when or after it transmits a retransmission of the L1 report corresponding to the L1 report configuration. The NE may perform the same timer management process, and it may schedule the retransmission of the L1 report when the timer is running and before the timer expires.
[0105] FIG. 13 illustrates a corresponding flow chart for the process of FIG. 12. The UE of the method 1300 starts by transmitting 1324A an L1 report. At the same time, or just before or after the transmitting, the UE starts 1340 a timer associated with buffer 219. The UE stores 1341 the transmitted L1 report in the buffer 219, for possible further retransmission. If an event is detected 1343 ( “Y” branch) , before the timer expires, then the UE may retransmit 1345 the stored L1 report. The event may be an indication from the NE that the initial L1 report 624A was not received. Other events related to the missing report may be used. However, if no event is detected 1343 ( “N” branch) and the timer is not expired 1347 ( “N” branch) , the method returns to step 1343 to check again for an event. This step is repeated until the timer expires. After the timer has expired 1347 ( “Y” branch) , the UE flushes 1349 the buffer and is ready to store a new L1 report.
[0106] In some embodiments, for a L1 report configuration, the NE may configure multiple processes for retransmission. Then the UE may maintain the buffer per process based on the above method. For the retransmission, the NE may indicate the corresponding process index. Then the UE performs the retransmission of the L1 report in the buffer corresponding to the process. In some embodiments, for UCI proces based retransmission, the UE may maintain the buffer per UCI process based on the above procedure separately.
[0107] FIG. 14 illustrates an embodiment 1400 for which the NE enables the retransmission for an L1 report configuration. The UE receives a TO 622A and sends the L1 report 624A based on the TO 622A. The NE further indicates 1450 whether it has correctly received the L1 report 624A. When transmitting at time 1440 the L1 report, the UE flushes the buffer and stores the transmitted L1 report 624A in the buffer, for the L1 report configuration. The UE maintains the L1 report in the buffer for a time period 1442, at least until the indication 1450 is received. After X symbols or slots 1452 after receiving the indication 1450, that the NE has correctly received the L1 report, the UE flushes at time 1454 the buffer for the L1 report configuration, where the value of X may be pre-defined, or configured by the NE via RRC signaling, MAC CE, or DCI, or reported by the UE via UE capability.
[0108] In some embodiments, the NE may provide the indication 1450 as an acknowledgement (ACK) for the L1 report by a PDCCH. The NE may transmit the PDCCH based on cell radio network temporary identifier (C-RNTI) or another RNTI configured by the NE.
[0109] FIG. 15 illustrates a flow chart of a UE method 1500 for flushing an existing L1 report stored in a buffer, based on the NE indication 1450 in FIG. 14. The method 1500 starts by transmitting 1524A the L1 report to the NE. The UE stores 1541 the L1 report in the buffer 219. For this embodiment, it is possible to not use a timer. The UE determines 1547 whether an NE indication has been received, for example, an indication from the NE that the L1 report has been received. If the UE determines that the NE indication has been received ( “Y” branch) , then the UE flushes 1549 the buffer and prepares for the next transmission. The UE may flush 1549 the buffer immediately after receiving the indication or after a given time. If the UE determines 1547 that the NE indication has not been received ( “N” branch) , for example, as another TO has been received for a next L1 report, the NE then retransmits 1545 the previously stored L1 report and then the method proceeds to step 1549.
[0110] In some embodiments, the NE may further configure a timer for retransmission of the L1 report corresponding to an L1 report configuration. The NE may configure an uplink resource (e.g., PUCCH or PUSCH resource) for the retransmission. The UE starts or restarts the timer after it transmits the L1 report. When the timer expires, the UE may perform the retransmission of the L1 report on the configured uplink resource. After receiving the indication of ACK of L1 report, the UE may stop the timer.
[0111] In some embodiments, the NE may configure a stop / flush time. The stop / flush time may be the same or prior to the start of the prediction window correlated with the L1 report. When the stop / flush time arrives, or before the stop / flush time arrives, if there is no available uplink resource (e.g., PUCCH or PUSCH resource) for the retransmission, the UE flushes the buffer for the L1 report.
[0112] In some embodiments, the NE may configure the indication to indicate the UE to perform actual measurements, e.g., during the prediction window, or to indicate the fallback to legacy measurement at the UE side. After receiving the indication, the UE may flush the buffer for the L1 report.
[0113] In some embodiments, for an L1 report configuration, the NE may configure multiple processes for retransmission. Then the NE may provide the indication of buffer management per process based on the method 1500. For the retransmission, the NE may indicate a corresponding process index. Then the UE performs the retransmission of the L1 report, stored in the buffer and corresponding to the process. In some embodiments, for UCI process based retransmission, the UE may separately maintain the buffer per UCI process based on the procedure above.
[0114] FIG. 16 illustrates a scenario 1600 in which for L1 report retransmission, a maximum buffer size 1602 may be pre-defined, or configured by the NE, or reported by the UE. The UE stores one or more L1 reports 1604 corresponding to an L1 report retransmission when the current buffer size is smaller than the maximum buffer size 1602, e.g., the maximum number of L1 report instances or maximum buffered bits. The maximum buffer size 1602 may be per BWP, per serving cell, per band, per band combination, per frequency range, or per UE. When a new L1 report 1606 needs to be added to the buffer, and thus, the target buffer size becomes greater than the maximum buffer size 1602, the UE removes 1608 at least one already stored L1 report 1604 based on the priority of the stored L1 reports, and adds the new L1 report 1606, to meet the maximum buffer size requirement as shown in FIG. 16.
[0115] FIG. 17 is a flow chart of a UE method 1700 that illustrates the process of FIG. 16. The method 1700 starts with the UE transmitting 1724A the L1 report. As the UE is configured to store the transmitted L1 report in the buffer 219, the UE determines 1760 whether the addition of the transmitted L1 report will require a buffer size larger than the maximum buffer size 1602 of the buffer 219. If the result of this determination 1760 is no ( “N” branch) , then the UE stores 1741 the transmitted L1 report in the buffer without removing existing L1 reports. However, if the result of the determination 1760 is yes ( “Y” branch) , then the UE removes 1764 one or more stored L1 reports with the lowest priority, and then stores 1741 the latest transmitted L1 report.
[0116] The NE and UE may determine the priority of the L1 reports (e.g., L1 report 2 1604 in FIG. 16) based on at least one of the following criteria:
[0117] · Serving cell for the CMR or L1 report, e.g., higher priority for the smaller serving cell index;
[0118] · Time-domain behavior for the report type (aperiodic, semi-persistent, periodic, or event-triggered) , e.g., the order of the priority may be: (event-triggered > aperiodic > semi-persistent > periodic) ;
[0119] · Report quantity, e.g., the order of the priority may be: L1-RSRP / L1-SINR > L1 report other than L1-RSRP / L1-SINR;
[0120] · L1 report configuration ID, e.g., higher priority for the smaller L1 report configuration ID; or
[0121] · Timing for the TOs of the L1 report or CMR for the L1 report, e.g., higher priority for later TOs.
[0122] Those skilled in the art would understand that the embodiments are not limited by these criterion, and other criterion may be used.
[0123] In some embodiments, for UCI process based retransmission, the UE may separately maintain the buffer, per UCI process, based on the above procedure. Thus, the L1 reports above may correspond to the same UCI process.
[0124] Reference throughout this section to “one embodiment” or “an embodiment” means that a particular feature, structure, or characteristic described in connection with an embodiment is included in at least one embodiment. Thus, the appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout the specification are not necessarily all referring to the same embodiment. Further, the particular features, structures or characteristics may be combined in any suitable manner in one or more embodiments.
[0125] Numerical adjectives “first” , “second” , and “third” do not imply any order (are not ordinals) but are markers to distinguish separate instances of similar elements. References to the singular (e.g., “a” or “an” , “the” ) should include the plural unless clearly indicated otherwise.
[0126] As used herein, a phrase referring to “at least one of” or “one or more of” a list of items refers to any combination of those items, including single members. For example, “at least one of: a, b, or c” is intended to cover the possibilities of: a only, b only, c only, a combination of a and b, a combination of a and c, a combination of b and c, and a combination of a and b and c.
[0127] Although the features and elements of the present embodiments are described in the embodiments in particular combinations, each feature or element can be used alone without the other features and elements of the embodiments or in various combinations with or without other features and elements disclosed herein. The methods or flow charts may be implemented in a computer program, software or firmware tangibly embodied in a computer-readable storage medium for execution by a specifically programmed computer or processor.
Claims
1.A method for wireless communication by a user equipment, UE, (210) , the method comprising:receiving (404) from a network entity, NE, (220) a control signal configuring a first layer 1, L1, report configuration with a retransmission indication being enabled;receiving (412) , from the NE (220) , a scheduling message for scheduling a retransmission of a first L1 report associated with the first L1 report configuration; andtransmitting (418) , to the NE (220) , the retransmission of the first L1 report.2.The method of Claim 1, wherein the scheduling message includes a status indication indicating a first value for an initial transmission of an L1 report or a second value for a retransmission of an L1 report.3.The method of any of Claims 1 or 2, wherein the control signal further configures a second L1 report configuration linked to the first L1 report configuration, wherein the first L1 report configuration is used for an initial transmission of the first L1 report and the second L1 report configuration is used for the retransmission of the first L1 report.4.The method of any of Claims 1 to 3, wherein the scheduling message specifies at least one transmission occasion, TO, prior to a latest TO, of a channel measurement resource, CMR, that is associated with the first L1 report.5.The method of any of Claims 1 to 4, further comprising:selecting, at the UE, one or more of plural uplink resources for the retransmission of the first L1 report.6.The method of any of Claims 1 to 5, wherein the transmitting includes transmitting the retransmission of the first L1 report as part of a first uplink control information, UCI.7.The method of Claim 6, further comprising:dropping the first UCI or a second UCI when the first and second UCIs overlap, ormultiplexing the first and second UCIs when the first and second UCIs overlap,wherein the second UCI includes at least one of an initial transmission of the first L1 report, a hybrid automatic repeat request-acknowledgement feedback, a scheduling request, or an uplink transmission occasion.8.The method of any of Claims 1 to 7, further comprising:responsive to the retransmission indication being enabled, storing the first L1 report in a buffer;starting a timer of the buffer when the UE transmits an initial transmission of the first L1 report; andperforming at least one of:resetting the timer of the buffer and removing the first L1 report from the buffer when the UE transmits the retransmission of the first L1 report, [Buffer, option 1]removing the first L1 report from the buffer after receiving an indication from the NE that the retransmission of the first L1 report has been received, or [Buffer, option 2]removing a lowest priority L1 report from the buffer to store the first L1 report.9.The method of any of Claims 1 to 8, further comprising:transmitting, to the NE, a UE capability message that includes at least one supported configuration for the retransmission of the first L1 report.10.The method of Claim 9, wherein the at least one supported configuration for the retransmission of the L1 report includes one or more of:supporting of L1 report retransmission,supported types of L1 report configuration for the L1 report retransmission,supported maximum number of instances of L1 report for retransmission,supported maximum number of L1 report configurations per component carrier (CC) or across CCs in a band or band combination for the L1 report retransmission,supported maximum duration of a timer for the L1 report buffer management,supported maximum or minimum buffer size for L1 report retransmission, orsupported maximum number of processes per CC or across CCs in a band or band combination for L1 report retransmission.11.A method for wireless communication by a network entity, NE, (220) , the method comprising:transmitting (504) to a user equipment, UE, (210) a control signal configuring a first layer 1, L1, report configuration with a retransmission indication being enabled;transmitting (512) , to the UE (210) , a scheduling message for scheduling a retransmission of a first L1 report associated with the first L1 report configuration; andreceiving (518) , at the NE, the retransmission of the first L1 report.12.The method of Claim 11, wherein the scheduling message includes a status indication indicating a first value for an initial transmission of an L1 report or a second value for a retransmission of an L1 report.13.The method of any of Claims 11 or 12, wherein the control signal further configures a second L1 report configuration linked to the first L1 report configuration, wherein the first L1 report configuration is used an initial transmission of the first L1 report, and the second L1 report configuration is used for the retransmission of the first L1 report.14.The method of any of Claims 11 to 13, wherein the scheduling message specifies at least one transmission occasion, TO, prior to a latest TO, of a channel measurement resource, CMR, that is associated with the first L1 report.15.[Corrected under Rule 26, 29.11.2024]The method of any of Claims 11 to 14, wherein the transmitting of the control signal further configures at least one of:a transmission of the L1 report based on uplink control information (UCI) or higher layer signaling,a timer for L1 report buffer management associated with the retransmission of the first L1 report, oran indication of acknowledgment of a received L1 report.16.The method of Claim 15, further comprising:sending an indication to the UE that the retransmission of the first L1 report has been received.17.A wireless communication device (210, 220) comprising a transceiver (213, 222) , a processor (216, 223) , and computer-readable storage media (217, 224) storing executable instructions for the processor to perform any one of methods recited in claims 1-16, using the transceiver.
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