WO2022116148A1

WO2022116148A1 - Methods and apparatuses for beam failure recovery

Info

Publication number: WO2022116148A1
Application number: PCT/CN2020/133885
Authority: WO
Inventors: Wei Ling; Chenxi Zhu; Bingchao LIU; Yi Zhang; Lingling Xiao
Original assignee: Lenovo Beijing Ltd
Current assignee: Lenovo Beijing Ltd
Priority date: 2020-12-04
Filing date: 2020-12-04
Publication date: 2022-06-09
Anticipated expiration: 2023-06-04

Abstract

Embodiments of the present disclosure relate to a method and apparatus for beam link recovery (BFR). An exemplary method can include: receiving configuration information indicating: at least one set of failure detection resources, at least including: a first set of failure detection resource associated with a first TRP index and a third set of failure detection resources associated with a secondary cell (SCell); and a set of dedicated periodic physical uplink control channel (PUCCH) resources; in the case that a radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold, transmitting a first positive link recovery request (LRR) in a first dedicated periodic PUCCH resource; and in the case that a radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold, transmitting a third positive LRR in a third dedicated periodic PUCCH resource.

Description

METHODS AND APPARATUSES FOR BEAM FAILURE RECOVERY

TECHNICAL FIELD

Embodiments of the present application generally relate to wireless communication technology, and in particular to a method and an apparatus for beam failure recovery, e.g., in multiple transmit-receive points (TRPs) .

BACKGROUND

Multi-TRP transmission has been introduced into New Radio (NR) . During multi-TRP transmission, two or more TRPs (or panels) may be used to transmit data to a user equipment (UE) to improve reliability and robustness. A work item description (WID) approved on multiple-input multiple-output (MIMO) in NR Release 17 (R17) includes a research topic, evaluating and, if needed, specifying beam-management-related enhancements for simultaneous multi-TRP transmission with multi-panel reception.

In addition, in Release 15 (R15) , a random access channel (RACH) -based beam failure recovery (BFR) is defined for primary cell (PCell) . In Release 16 (R16) , a medium access control (MAC) control element (CE) -based BFR is defined for secondary cell (SCell) . However, the above BFRs for PCell and SCell are only defined in single-TRP transmission. For multi-TRP transmission, the BFR should be reconsidered. For example, a TRP specific beam failure recovery request (BFRQ) may be triggered for a TRP when all the beam failure detection (BFD) reference signals (RSs) associated with the TRP failed.

It is agreed in the standard documents that the TRP specific BFRQ is based on the SCell BFRQ. However, the relationship between the dedicated physical uplink control channel (PUCCH) resource configured for TRP specific BFRQ and the dedicated PUCCH resource configured for SCell BFRQ has not been discussed yet.

Given the above, it is desirable to provide an improved technology for beam failure recovery in multiple TRPs, so as to configure and transmit the dedicated PUCCH resources for TRP specific BFRQ and SCell BFRQ.

SUMMARY OF THE APPLICATION

One objective of the present application is to provide a technical solution for beam failure recovery, e.g., in multiple TRPs.

According to some embodiments of the present application, a method may include: receiving configuration information indicating: at least one set of failure detection resources, at least including: a first set of failure detection resource associated with a first TRP index and a third set of failure detection resources associated with a SCell; and a set of dedicated periodic PUCCH resources; in the case that a radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold, transmitting a first positive link recovery request (LRR) in a first dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources; and in the case that a radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold, transmitting a third positive LRR in a third dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources, wherein the first dedicated periodic PUCCH resource and third dedicated periodic PUCCH resource are the same or different.

In an embodiment of the present application, the at least one set of failure detection resources further includes a second set of failure detection resources associated with a second TRP index.

In another embodiment of the present application, the first set of failure detection resources and second set of failure detection resources are configured in a PCell or a PSCell.

In another embodiment of the present application, the first dedicated periodic PUCCH resource is a dedicated periodic PUCCH resource in the PCell or the PSCell.

In another embodiment of the present application, the first dedicated periodic PUCCH resource is configured with two spatial relation information and is configured with a beam mapping pattern to indicate which spatial relation information is used in each transmission occasion of the first dedicated periodic PUCCH resource, and the method may further include: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using a second spatial relation information associated with the second TRP index; and in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using first spatial relation information associated with the first TRP index.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource, and a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in a same PCell or PSCell.

In another embodiment of the present application, the method may further include: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index; and in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a physical uplink shared channel (PUSCH) carrying a medium access control (MAC) control element (CE) to indicate that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, wherein a PUSCH resource for transmitting the PUSCH is requested by a scheduling request (SR) transmitted in a PUCCH resource configured by a radio resource control (RRC) signaling.

In another embodiment of the present application, the set of dedicated periodic PUCCH resources further includes a second dedicated periodic PUCCH resource in the PCell or the PSCell, and the method further includes: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index; and in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in the second dedicated periodic PUCCH resource with first spatial relation information associated with the second TRP index.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is the same as one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In another embodiment of the present application, a priority of a positive LRR transmitted in the third dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the other one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In another embodiment of the present application, a priority of a positive LRR transmitted in the third dedicated periodic PUCCH resource is lower than that of a positive LRR transmitted in the other one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In another embodiment of the present application, a priority of a positive LRR of a lower TRP index transmitted in one dedicated periodic PUCCH resource of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is higher than that of a positive LRR of a higher TRP index transmitted in the other dedicated periodic PUCCH resource of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is different from any of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource; and in the case that the third dedicated periodic PUCCH resource and both of the first and the second dedicated periodic PUCCH resource are configured in a same PCell or PSCell, a priority of a positive LRR transmitted in any of the first dedicated periodic PUCCH resource and the second is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.

In another embodiment of the present application, wherein the first dedicated periodic PUCCH resource is configured in a PUCCH-SCell, and the method further includes: in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in the first dedicated periodic PUCCH resource.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resources, and a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in a same PUCCH-SCell.

In another embodiment of the present application, the first set of failure detection resources and second set of failure detection resources are configured in a SCell, wherein the first dedicated periodic PUCCH resource is the same as the third dedicated periodic PUCCH resource, and the method includes: in the case that radio link quality of all failure detection resources in the second set of failure detection resources are lower than a second threshold, transmitting a second positive LRR in the first dedicated periodic PUCCH resource.

In another embodiment of the present application, the TRP index is one of the following: a CORESETPoolIndex value; a failure detection resource set index; a candidate resource set index; and a RRC configured index other than a CORESETPoolIndex value, a failure detection resource set index and a candidate resource set index.

According to some embodiments of the present application, a method may include: transmitting configuration information indicating: at least one set of failure detection resources, at least including: a first set of failure detection resource associated with a first TRP index and a third set of failure detection resources associated with a SCell; and a set of dedicated periodic PUCCH resources; in the case that a radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold, receiving a first positive LRR in a first dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources; and in the case that a radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold, receiving a third positive LRR in a third dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources, wherein the first dedicated periodic PUCCH resource and third dedicated periodic PUCCH resource are the same or different.

In another embodiment of the present application, the first dedicated periodic PUCCH resource is configured with two spatial relation information and is configured with a beam mapping pattern to indicate which spatial relation information is used in each transmission occasion of the first dedicated periodic PUCCH resource, and the method includes: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, receiving the first positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using a second spatial relation information associated with the second TRP index; and in the case that radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, receiving a second positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using first spatial relation information associated with the first TRP index.

In another embodiment of the present application, the method may further include: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, receiving the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index; and in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, receiving a PUSCH carrying a MAC CE to indicate that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, wherein a PUSCH resource for receiving the PUSCH is requested by a SR received in a PUCCH resource configured by a RRC signaling.

In another embodiment of the present application, the set of dedicated periodic PUCCH resources further includes a second dedicated periodic PUCCH resource in the PCell or the PSCell, and the method further includes: in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, receiving the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index; and in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, receiving a second positive LRR in the second dedicated periodic PUCCH resource with first spatial relation information associated with the first TRP index.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is different from any of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource; and in the case that the third dedicated periodic PUCCH resource and both of the first and the second dedicated periodic PUCCH resource are configured in a same PCell or PSCell, a priority of a positive LRR transmitted in any of the first dedicated periodic PUCCH resource and the second periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.

In another embodiment of the present application, the first dedicated periodic PUCCH resource is configured in a PUCCH-SCell, and the method further includes: in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, receiving a second positive LRR in the first dedicated periodic PUCCH resource.

In another embodiment of the present application, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resources, and wherein a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in a same PUCCH-SCell.

In another embodiment of the present application, the first set of failure detection resources and second set of failure detection resources are configured in a SCell, wherein the first dedicated periodic PUCCH resource is the same as the third dedicated periodic PUCCH resource, and the method includes: in the case that radio link quality of all failure detection resources in the second set of failure detection resources are lower than a second threshold, receiving a second positive LRR in the first dedicated periodic PUCCH resource.

Some embodiments of the present application also provide an apparatus, include: at least one non-transitory computer-readable medium having computer executable instructions stored therein; at least one receiving circuitry; at least one transmitting circuitry; and at least one processor coupled to the at least one non-transitory computer-readable medium, the at least one receiving circuitry and the at least one transmitting circuitry. The computer executable instructions are programmed to implement any method as stated above with the at least one receiving circuitry, the at least one transmitting circuitry and the at least one processor.

Embodiments of the present application provide a technical solution for beam failure recovery in multiple TRPs, so as to configure and transmit the dedicated PUCCH resources for TRP specific BFRQ and SCell BFRQ, thereby facilitating the beam management in the multi-TRP transmission.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to describe the manner in which advantages and features of the application can be obtained, a description of the application is rendered by reference to specific embodiments thereof, which are illustrated in the appended drawings. These drawings depict only example embodiments of the application and are not therefore to be considered limiting of its scope.

FIG. 1 is a schematic diagram illustrating an exemplary wireless communication system according to some embodiments of the present application;

FIG. 2 is a flow chart illustrating a method for beam failure recovery according to some embodiments of the present application;

FIG. 3 illustrates an exemplary procedure of LRR transmission according to some embodiments of the present application;

FIG. 4 illustrates another exemplary procedure of LRR transmission according to some other embodiments of the present application;

FIG. 5 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application;

FIG. 6 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application;

FIG. 7 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application;

FIG. 8 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application; and

FIG. 9 illustrates a simplified block diagram of an apparatus for beam failure recovery according to some embodiments of the present application.

DETAILED DESCRIPTION

The detailed description of the appended drawings is intended as a description of the preferred embodiments of the present application and is not intended to represent the only form in which the present application may be practiced. It should be understood that the same or equivalent functions may be accomplished by different embodiments that are intended to be encompassed within the spirit and scope of the present application.

Reference will now be made in detail to some embodiments of the present application, examples of which are illustrated in the accompanying drawings. To facilitate understanding, embodiments are provided under specific network architecture and new service scenarios, such as the 3rd generation partnership project (3GPP) 5G (NR) , 3GPP long-term evolution (LTE) Release 8, and so on. It is contemplated that along with the developments of network architectures and new service scenarios, all embodiments in the present application are also applicable to similar technical problems; and moreover, the terminologies recited in the present application may change, which should not affect the principle of the present application.

A wireless communication system generally includes one or more base stations (BSs) and one or more UEs. Furthermore, a BS may be configured with one TRP (or panel) or more TRPs (or panels) . A TRP can act like a small BS. The TRPs can communicate with each other by a backhaul link. Such backhaul link may be an ideal backhaul link or a non-ideal backhaul link. Latency of the ideal backhaul link may be deemed as zero, and latency of the non-ideal backhaul link may be tens of milliseconds and much larger, e.g. on the order of tens of milliseconds, than that of the ideal backhaul link.

In a wireless communication system, a single TRP can be used to serve one or more UEs under the control of a BS. In different scenarios, a TRP may be referred to as different terms. Persons skilled in the art should understand that as the 3rd Generation Partnership Project (3GPP) and the communication technology develop, the terminologies recited in the specification may change, which should not affect the scope of the present application. It should be understood that the TRP (s) (or panel (s) ) configured for the BS may be transparent to a UE.

FIG. 1 is a schematic diagram illustrating an exemplary wireless communication system 100 according to some embodiments of the present application.

Referring to FIG. 1, a wireless communication system 100 can include a base station (BS) 101, TRPs 103 (e.g., a TRP 103a and a TRP 103b) , and UEs 105 (e.g., a UE 105a, a UE 105b, and a UE 105c) . Although only one base station 101, two TRPs 103 and three UEs 105 are shown for simplicity, it should be noted that the wireless communication system 100 may include more or less communication device (s) or apparatus in accordance with some other embodiments of the present application.

In some embodiments of the present application, a BS 101 may be referred to as an access point, an access terminal, a base, a base unit, a macro cell, a Node-B, an evolved Node B (eNB) , a gNB, an ng-eNB, a Home Node-B, a relay node, or a device, or described using other terminology used in the art. The UEs 105 (for example, the UE 105a, the UE 105b, and the UE 105c) may include, for example, but is not limited to, a computing device, a wearable device, a mobile device, an IoT device, a vehicle, etc.

The TRPs 103, for example, the TRP 103a and the TRP 103b can communicate with the base station 101 via, for example, a backhaul link. Each of TRPs 103 can serve some or all of UEs 105. As shown in FIG. 1, the TRP 103a can serve some mobile stations (which include the UE 105a, the UE 105b, and the UE 105c) within a serving area or region (e.g., a cell or a cell sector) . The TRP 103b can serve some mobile stations (which include the UE 105a, the UE 105b, and the UE 105c) within a serving area or region (e.g., a cell or a cell sector) . The TRP 103a and the TRP 103b can communicate to each other via, for example, a backhaul link.

The multi-TRP transmission may refer to at least two TRPs (or panels) to transmit data to a UE. As shown in FIG. 1, for the same UE 105 (e.g., the UE 105a, the UE 105b, or the UE 105c) , two TRPs (e.g., the TRP 103a and the TRP 103b) may both transmit data to it, which is an exemplary scenario of the multi-TRP transmission.

In addition, regarding BFR during transmission, both PCell BFR and SCell BFR only consider single-TRP transmission. For multiple-TRP transmission, the beam (represent by "spatial relation information" ) failure recovery should be reconsidered.

For example, according to one workable mechanism, the beam failure recovery in the multiple-TRP transmission can be performed for each TRP, respectively. In order to detect the beam condition per TRP, separate beam failure detection RSs may be configured for each TRP in the multiple-TRP transmission. Similar to the beam failure detection RSs, separate new candidate beams can also be configured for each TRP in the in the multiple-TRP transmission. When a beam failure is detected for a TRP, the beam failure information as well as new candidate beam information may be transmitted via an available link to another TRP.

A TRP specific BFRQ, which is based on the SCell BFRQ may be triggered for a TRP when all the BFD RSs associated with the TRP failed. For the SCell BFRQ, the beam failure of a SCell may be reported by a PUCCH-BFR resource followed by a MAC CE which indicates the failed SCell index (es) and the corresponding new beam index (es) . Accordingly, for the TRP specific BFRQ, a PUCCH-BFR resource may be configured to report the beam failure of the specific TRP.

However, in the case that both TRP specific BFRQ and SCell BFRQ are configured for a UE, how many PUCCH-BFR resources for the TRP specific BFRQ and SCell BFRQ should be configured, the relationship between the PUCCH-BFR resources configured for the TRP specific BFRQ and the PUCCH-BFR resources configured for the SCell BFRQ, and how to report the beam failure of at least one of one or more TRP and SCell have not been discussed yet.

Embodiments of the present application provide solutions for beam failure recovery, which can at least solve the above three technical problems, thereby improving the beam management in the multi-TRP transmission. More details on embodiments of the present application will be illustrated in the following text in combination with the appended drawings.

FIG. 2 is a flow chart illustrating a method for beam failure recovery in multi-TRP transmission according to some embodiments of the present application. Although the method is illustrated in a system level by a UE and a BS (e.g., the UE 105 and the BS 101 as illustrated and shown in FIG. 1) , persons skilled in the art can understand that the method implemented in the UE and that implemented in the BS can be separately implemented and incorporated by other apparatus with the like functions.

In the exemplary method in FIG. 2, in step 201, the BS 101 may transmit configuration information to the UE 105.

According to some embodiments of the present application, the configuration information may indicate at least one set of failure detection resources. Each set of failure detection resources may be associated with a TRP index or a SCell, and include one or more failure detection resource. The at least one set of failure detection resources may at least include a first set of failure detection resource associated with a first TRP index (e.g., an index of the TRP 103a) and a third set of failure detection resources associated with a SCell. In an embodiment of the present application, the at least one set of failure detection resources may include a first set of failure detection resource associated with a first TRP index (e.g., an index of the TRP 103a) , a second set of failure detection resource associated with a second TRP index (e.g., an index of the TRP 103b) , and a third set of failure detection resources associated with a SCell. In another embodiment of the present application, in addition to the first, second, and third sets of failure detection resources, the at least one set of failure detection resources may also include one or more other sets of failure detection resources, each of the one or more other sets of failure detection resources may be associated with a different TRP index other than the first TRP index and the second TRP index.

In an embodiment of the present application, each set of failure detection resources may be configured by a RRC signaling. For example, each set of failure detection resources may be a set of periodic channel state information-reference signal (CSI-RS) resource configuration indexes configured by the RRC signaling. When there is no set of failure detection resources configured by the RRC signaling, the UE may determine each set of failure detection resources to include periodic CSI-RS resource configuration indexes with the same values as the RS indexes in the RS sets indicated by a transmission configuration indicator (TCI) state for respective control resource sets (CORESETs) that the UE uses for monitoring PDCCH. When there are two RS indexes in a TCI state, each set of failure detection resources may include RS indexes with quasi co-location (QCL) -TypeD configuration for the corresponding TCI state.

According to some embodiments of the present application, the configuration information may indicate at least one set of candidate resources. Each set of the at least one set of candidate resources may be associated with a TRP index or a SCell. The at least one set of candidate resources may at least include a first set of candidate resource associated with a first TRP index (e.g., an index of the TRP 103a) and a third set of candidate resources associated with a SCell. In an embodiment of the present application, the at least one set of candidate resources may include a first set of candidate resource associated with a first TRP index (e.g., an index of the TRP 103a) , a second set of candidate resource associated with a second TRP index (e.g., an index of the TRP 103b) , and a third set of candidate resources associated with a SCell. In another embodiment of the present application, in addition to the first, second, and third sets of candidate resources, the at least one set of candidate resources may also include one or more other sets of candidate resources, and each of the one or more other sets of candidate resources may be associated with a different TRP index other than the first TRP index and the second TRP index.

In an embodiment of the present application, each set of candidate resources may include at least one of the following: a set of periodic CSI-RS resource configuration indexes, and a set of synchronization signal (SS) /physical broadcast channel (PBCH) block indexes.

According to some embodiments of the present application, the configuration information may indicate a set of dedicated periodic PUCCH resources. The set of dedicated periodic PUCCH resources may include one or more dedicated periodic PUCCH resources, which are used for report the beam failure (or BRFQs) of at least one of the one or more TRPs and SCell. For example, each dedicated periodic PUCCH resource may be a SR-like PUCCH resource configured by a RRC signaling with periodic transmission to indicate a LRR of at least one of the one or more TRPs and SCell. The priority of a positive LRR transmitted in each dedicated periodic PUCCH resource is higher than that of a positive SR transmitted in the PUCCH resource configured for transmitting the SR.

In an embodiment of the present application, the set of dedicated periodic PUCCH resources may include a first dedicated periodic PUCCH resource for transmitting a first positive LRR of the first TRP and a third set of dedicated periodic PUCCH resources for transmitting a third positive LRR of the SCell. The first set of failure detection resources and the third set of dedicated periodic PUCCH resources may be the same or different.

According to some embodiments of the present application, the TRP index may be one of the following: a CORESETPoolIndex value as specified in 3GPP standard documents, a failure detection resource set index, a candidate resource set index, and a RRC configured index other than a CORESETPoolIndex value, a failure detection resource set index and a candidate resource set index mentioned before. For example, in a scenario of multi-downlink control information (DCI) based multiple TRPs, the CORESETPoolIndex value can be used as a TRP index to distinguish different TRPs. In a scenario of single-DCI based multiple TRPs, the failure detection resource index, the candidate resource set index or a new RRC configured index can be used as a TRP index to distinguish different TRPs.

Consequently, in step 202, the UE 105 may receive the configuration information from the BS 101. After receiving the configuration information, the UE 105 may access the radio link quality of each set of the at least one set of failure detection resources.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold (e.g., all beams in the first set of failure detection resources failed or a beam failure for the first TRP is detected) , in step 203, the UE 105 may transmit a first positive LRR in the first dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources to the BS 101. Consequently, the BS 101 may receive the first positive LRR in the first dedicated periodic PUCCH resource in step 204. The UE 105 may transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resources) of the first TRP (e.g., the TRP 103a) to the BS 101.

In the case that the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold (e.g., all beams in the third set of failure detection resources failed or a beam failure for the SCell is detected) , in step 205, the UE 105 may transmit a third positive LRR in the third dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources to the BS 101. Consequently, the BS 101 may receive the third positive LRR in the third dedicated periodic PUCCH resource in step 206. The UE 105 may transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell to the BS 101. The first threshold and the third threshold may be configured by the BS 101 and may be the same or different.

Considering there are two TRPs are supported in R16/R17 now, embodiments of the present application may use two TRPs for illustration. It should be noted that more than two TRPs can also be supported by using the methods disclosed below.

In the case that the multi-TRP transmission is a two-TRP transmission, the at least one set of failure detection resources may include a first set of failure detection resources associated with a first TRP index (e.g., an index of the TRP 103a) , and a second set of failure detection resources associated with a second TRP index (e.g., an index of the TRP 103b) .

Case 1

According to some embodiments of the present application, the first set of failure detection resources and second set of failure detection resources may be configured in a PCell or a PSCell (hereinafter referred to as case 1) . In other words, case 1 means two TRPs will be deployed in PCell or PSCell in order to support TRP specific BFRQ.

In case 1, in some embodiments, the first dedicated periodic PUCCH resource is a dedicated periodic PUCCH resource in the PCell or the PSCell. The first dedicated periodic PUCCH resource may be used for two TRPs to report the TRP specific BFRQs for the two TRPs. The first dedicated periodic PUCCH resource may be configured with two spatial relation information (e.g., two beams) . The BS 101 may also configure the correspondence between the two spatial relation information and the two TRP indexes. For example, the two spatial relation information may include first spatial relation information associated with the first TRP index and second spatial relation information associated with the second TRP index.

In addition, the first dedicated periodic PUCCH resource may also be configured with a beam mapping pattern to indicate which spatial relation information is used in each transmission occasion of the first dedicated periodic PUCCH resource.

In an embodiment, the beam mapping pattern may be a cyclical mapping pattern. For example, for two spatial relation information, e.g., spatial relation information #1 and spatial relation information #2, when the cyclical mapping pattern is configured, the first and second spatial relation information are applied to the first and second transmission occasions, respectively, and the same mapping pattern continues to the remaining transmission occasions. Accordingly, the cyclical mapping pattern might be #1#2#1#2#1#2#1#2…for a sequence of transmission occasions.

In another embodiment, the beam mapping pattern may be a sequential mapping pattern. For example, for two spatial relation information, e.g., spatial relation information #1 and spatial relation information #2, when the sequential mapping pattern is configured, the first spatial relation information is applied to the first and second transmission occasions, and the second spatial relation information is applied to the third and fourth transmission occasions, and the same mapping pattern continues to the remaining transmission occasions. Accordingly, the sequential mapping pattern might be #1#1#2#2#1#1#2#2…for a sequence of transmission occasions.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold (e.g., all beams in the first set of failure detection resources are failed or a beam failure is detected for the first TRP) , the UE 105 may transmit the first positive LRR in a transmission occasion using a second spatial relation information associated with the second TRP index of the first dedicated periodic PUCCH resource to the BS 101. The UE 105 may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resource) of the first TRP (e.g., the TRP 103a) to the BS 101.

In the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than the second threshold (e.g., all beams in the second set of failure detection resources are failed or a beam failure is detected for the second TRP) , the UE 105 may transmit the second positive LRR in a transmission occasion using first spatial relation information associated with the first TRP index of the first dedicated periodic PUCCH resource to the BS 101. After that, the UE 105 may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of the second TRP (e.g., the TRP 103b) to the BS 101. The second threshold may be configured by the BS 101 and may be the same or different from the first threshold.

Considering whether SCell BFRQ and TRP specific BFRQ are configured at the same time for the same UE, there are two options, i.e., option 1 and option 2 regarding how to configure the dedicated periodic PUCCH resource for SCell BFRQ and TRP specific BFRQ.

Option 1: The dedicated periodic PUCCH resource configured for TRP specific BFRQ may be reused for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource. That is, the first dedicated periodic PUCCH resource is used to transmit the first LRR of the first TRP, the second LRR of the second TRP, and the third LRR of the SCell.

FIG. 3 illustrates an exemplary procedure of LRR transmission according to some embodiments of the present application with option 1 in case 1.

Referring to FIG. 3, the first TRP, e.g., TRP 1 and the second TRP, e.g., TRP 2 are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP2. A first dedicated periodic PUCCH resource, e.g., PUCCH resource 1 with two beams, e.g., beam 1 and beam 2 is configured for both TRP 1 and TRP 2, wherein beam 1 is associated with the TRP 1 and beam 2 is associated with TRP 2. A cyclic mapping pattern is configured for the PUCCH resource 1 to indicate the beam for each transmission occasion. PUCCH resource 1 may be reused for BFRQ of a SCell. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 3, in transmission occasion t1, the UE 105 may detect a beam failure of TRP 1 (e.g., the radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold) , and may transmit a beam failure report of TRP 1 (e.g., a first positive LRR) in transmission occasion t2 of PUCCH resource 1 using beam 2 associated with TRP 2 to the BS. After transmitting the first positive LRR in t2, the UE may transmit a PUSCH carrying the MAC CE which includes a new beam indication of TRP 1 in t3. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resources) of TRP 1. Considering that all beams of TRP 1 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 2 as shown in FIG. 3 when the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

Similarly, in transmission occasion t4, the UE 105 may detect a beam failure of TRP 2 (e.g., the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold) , and may transmit a beam failure report of TRP 2 (e.g., a second positive LRR) in transmission occasion t5 of PUCCH resource 1 using beam 1 associated with TRP 1. After transmitting the second positive LRR in t5, the UE may transmit a PUSCH carrying the MAC CE which includes a new beam indication of TRP 2 in t6. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of TRP 2. Considering that all beams of TRP 2 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 1 as shown in FIG. 3 when the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In transmission occasion t7, the UE 105 may detect a beam failure of SCell (e.g., the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold) , and may transmit a beam failure report of SCell (e.g., a third positive LRR) in transmission occasion t8 of PUCCH resource 1 using beam 2 associated with TRP 2 to the BS. Since the BS cannot distinguish the first positive LRR of TRP1 and the third positive LRR of SCell when receiving the LRR in PUCCH resource 1 in t8, it will schedule a PUSCH such that the UE may transmit the PUSCH carrying the MAC CE in t9 to TRP 2 after transmitting the LRR in t8. The PUSCH carrying the MAC CE transmitted in t9 may indicate the failed beam (s) of SCell and may include a new beam indication of the SCell. The new beam indication may indicate at least one new candidate beam (i.e., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in another SCell whose beam does not fail.

Option 2: Except for the first dedicated periodic PUCCH resource configured for TRP specific BFRQ of both the first and second TRP, another dedicated periodic PUCCH resource may be configured for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource.

In an embodiment, the third dedicated periodic PUCCH resource may also be configured in a PCell or a PSCell. Since there are two dedicated periodic PUCCH resources in PCell or a PSCell for LRR transmission, a priority between the two dedicated periodic PUCCH resources should be determined. Considering the radio link quality of the PCell or PSCell is more important than the SCell, when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in the same PCell or PSCell, a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.

In another embodiment, the third dedicated periodic PUCCH resource may be configured in PUCCH-SCell, and the first dedicated periodic PUCCH resource for TRP specific BFRQ will not overlap with the third dedicated periodic PUCCH resource for SCell BFRQ due to being in different cells. Therefore, no priority is necessary to be determined for the two dedicated periodic PUCCH resources.

FIG. 4 illustrates another exemplary procedure of LRR transmission according to some other embodiments of the present application with option 2 in case 1.

Referring to FIG. 4, the first TRP, e.g., TRP 1 and the second TRP, e.g., TRP 2 are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP2. A first dedicated periodic PUCCH resource, e.g., PUCCH resource 1 with two beams, e.g., beam 1 and beam 2 is configured for both TRP1 and TRP2, wherein beam 1 is associated with the TRP 1 and beam 2 is associated with TRP 2. A cyclic mapping pattern is configured for the PUCCH resource 1 to indicate the beam for each transmission occasion. The third dedicated periodic PUCCH resource, e.g., PUCCH resource 2 may be configured for the BFRQ of a SCell. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 4, the steps performed before transmission occasion t7 are the same as those in FIG. 3, and will not repeat. In t7, when the UE detects that the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold (e.g., a beam failure for the SCell is detect) , the UE may transmit a beam failure report, e.g., the third positive LRR of the SCell in PUCCH resource 2 in t8. The UE may also transmit a PUSCH carrying the MAC CE which includes a new beam indication of the SCell in t9 in a PCell or a PSCell. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in another SCell whose beam does not failed.

In some other embodiments, the first dedicated periodic PUCCH resource may only be used for one TRP of the two TRPs to report the TRP specific BFRQ. For example, the BS 101 may configure the first dedicated periodic PUCCH resource to be used to transmit the LRR (or report the TRP specific BFRQ) of the first TRP (e.g., the TRP 103a) .

Moreover, the first dedicated periodic PUCCH resource may be configured with one spatial relation information, e.g., one beam. In an embodiment, the correspondence between the spatial relation information and the TRP index is configured by the BS. For example, the BS may configure that the spatial relation information is associated the second TRP index, such that the first dedicated periodic PUCCH resource may be associated with the second TRP. In another embodiment, the correspondence between the first dedicated periodic PUCCH resource and the TRP index is configured by the BS. For example, the BS may configure that the first dedicated periodic PUCCH resource is associated with the second TRP. For the second TRP (e.g., the TRP 103b) , the UE may use a PUSCH carrying a MAC CE to report the TRP specific BFRQ of the second TRP, and the PUSCH resource for transmitting the PUSCH may be requested by a SR.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold (e.g., all beams in the first set of failure detection resources are failed or a beam failure is detected for the first TRP) , the UE may transmit the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index to the BS. The UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resource) of the first TRP (e.g., the TRP 103a) to the BS.

In the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold (e.g., all beams in the second set of failure detection resources are failed or a beam failure is detected for the second TRP) , the UE may transmit a PUSCH carrying a MAC CE to indicate that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than the second threshold. The PUSCH resource for transmitting the PUSCH is requested by a SR transmitted in a PUCCH resource configured by a RRC signaling.

Considering whether SCell BFRQ and TRP specific BFRQ are configured at the same time for the UE, there are two options, i.e., option 3 and option 4 regarding how to configure the dedicated periodic PUCCH resource for SCell BFRQ and TRP specific BFRQ.

Option 3: The first dedicated periodic PUCCH resource configured for TRP specific BFRQ of TRP 1 may be reused for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource. That is, the first dedicated periodic PUCCH resource is used to transmit the first positive LRR of the first TRP and the third positive LRR of the SCell.

FIG. 5 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application with option 3 in case 1.

Referring to FIG. 5, the first TRP (e.g., TRP 1) and the second TRP (e.g., TRP 2) are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP2. A first dedicated periodic PUCCH resource for TRP specific BFRQ (e.g., PUCCH resource 1) with beam 2 is configured by the BS, wherein beam 2 is associated with the TRP 2. PUCCH resource 1 may be reused for BFRQ of a SCell. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 5, in transmission occasion t1, the UE may detect a beam failure of TRP 1 (e.g., , the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold) , and may transmit a beam failure report of TRP 1 (e.g., a first positive LRR) in transmission occasion t2 of PUCCH resource 1 using beam 2 associated with TRP 2 to the BS. After transmitting the first positive LRR in t2, the UE may transmit a PUSCH carrying the MAC CE which includes a new beam indication of TRP 1 in t3. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resources) of TRP 1. Considering that all beams of TRP 1 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 2 as shown in FIG. 5 when the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In transmission occasion t4, the UE may detect a beam failure of TRP 2 (e.g., the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold) . The UE may use a PUSCH to carry a MAC CE to transmit a beam failure report and a new beam indication of TRP2. Assuming that a PUCCH resource 2 is to transmit a SR in t4, the UE may transmit the SR in PUCCH resource 2 to the BS, and then the BS may schedule a PUSCH in t6 such that the UE may transmit a PUSCH carrying a MAC CE in t6. The PUSCH carrying the MAC CE may indicate that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold and may also include a new beam indication of TRP 2. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of TRP 2. Considering that all beams of TRP 2 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 1 as shown in FIG. 5 when the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In transmission occasion t7, the UE may detect a beam failure of a SCell (e.g., the radio link quality of all failure detection resources in the third set of failure detection resources is lower than third threshold) , and may transmit a beam failure report of the SCell (e.g., a third positive LRR) in transmission occasion t8 of PUCCH resource 1 using beam 2 associated with TRP 2 to the BS. Since the BS cannot distinguish the first positive LRR of TRP1 and the third positive LRR of SCell when receiving the LRR in PUCCH resource 1 in t8, the BS will schedule a PUSCH such that the UE may transmit the PUSCH carrying the MAC CE in t9 to TRP 2. The PUSCH carrying the MAC CE transmitted in t9 may indicate the failed beam (s) of the SCell and may include a new beam indication of the SCell. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in another SCell whose beam does not fail.

Option 4: Except for the first dedicated periodic PUCCH resource configured for TRP specific BFRQ of the first TRP, another dedicated periodic PUCCH resource may be configured for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource.

In an embodiment, the third dedicated periodic PUCCH resource may also be configured in a PCell or a PSCell. Since there are two dedicated periodic PUCCH resources in PCell or a PSCell, a priority between the two dedicated periodic PUCCH resources should be determined. Considering the radio link quality of the PCell or a PSCell is more important than the SCell, when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in the same PCell or PSCell, a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.

FIG. 6 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application with option 4 in case 1.

Referring to FIG. 6, the first TRP (e.g., TRP 1) and the second TRP (e.g., TRP 2) are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP2. A first dedicated periodic PUCCH resource (e.g., PUCCH resource 1) with beam 2 is configured by the BS, wherein beam 2 is associated with TRP 2. The third dedicated periodic PUCCH resource (e.g., PUCCH resource 3) may be configured for the BFRQ of a SCell. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 6, the steps performed before transmission occasion t7 are the same as those in FIG. 6, and will not repeat. In t7, when the UE detects that the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold (e.g., a beam failure for the SCell is detected) , the UE may transmit a beam failure report (i.e., the third positive LRR) of the SCell in PUCCH resource 3 in t8 to the BS 101. The UE may also transmit a PUSCH carrying the MAC CE which includes a new beam indication of the SCell in t9 in a PCell or a PSCell. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In some other embodiments, two dedicated periodic PUCCH resources in the PCell or the PSCell may be configured for the two TRPs. Each dedicated periodic PUCCH resource may be associated with a corresponding TRP of the two TRPs. For example, the two dedicated periodic PUCCH resources may include a first dedicated periodic PUCCH resource configured for beam failure report of the first TRP index and a second dedicated periodic PUCCH resource configured for beam failure report of the second TRP index.

Each of the first and second dedicated periodic PUCCH resource may be configured with spatial relation information. For example, the first dedicated periodic PUCCH resource may be configured with second spatial relation information and the second dedicated periodic PUCCH resource may be configured with first spatial relation information. In an embodiment, the correspondence between the spatial relation information and the TRP index is configured by the BS. For example, the BS may configure that the first spatial relation information is associated the first TRP index and the second spatial relation information is associated the second TRP index.

In another embodiment, the BS may also configure the correspondence between the two dedicated periodic PUCCH resources and the two TRP indexes for transmission. For example, the BS may configure that the first dedicated PUCCH resource is associated with the second TRP index which means that it is transmitted to the second TRP index and the second dedicated PUCCH resource is associated with the first TRP index which means it is transmitted to first TRP index.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold (e.g., all beams in the first set of failure detection resources are failed or a beam failure is detected for the first TRP) , the UE 105 may transmit the first positive LRR in the first dedicated periodic PUCCH resource with a second spatial relation information associated with the second TRP index to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resource) of the first TRP (e.g., the TRP 103a) to the BS.

In the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than the second threshold (e.g., all beams in the second set of failure detection resources are failed or a beam failure is detected for the second TRP) , the UE may transmit the second positive LRR in the second dedicated periodic PUCCH resource with first spatial relation information associated with the first TRP index to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resource) of the second TRP (e.g., the TRP 103b) to the BS.

Considering whether SCell BFRQ and TRP specific BFRQ are configured at the same time for the UE, there are two options, i.e., option 5 and option 6 regarding how to configure the dedicated periodic PUCCH resource for SCell BFRQ and TRP specific BFRQ.

Option 5: One of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is reused for SCell BFRQ. That is, the third dedicated periodic PUCCH resource is the same as one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource. Since there are two dedicated periodic PUCCH resources in PCell or a PSCell, a priority between the two dedicated periodic PUCCH resources should be determined.

In an embodiment of the present application, a priority of a positive LRR transmitted in the third dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the other one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource. For example, assuming that the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource, then the priority of a positive LRR transmitted in first dedicated periodic PUCCH resource is higher than a priority of a positive LRR transmitted in the second dedicated periodic PUCCH resource.

In another embodiment of the present application, a priority of a positive LRR transmitted in the third dedicated periodic PUCCH resource is lower than that of a positive LRR transmitted in the other one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource. For example, assuming that the first dedicated periodic PUCCH resource is the same as the third dedicated periodic PUCCH resource, then the priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is lower than a priority of a positive LRR transmitted in the second dedicated periodic PUCCH resource.

In yet another embodiment of the present application, a priority of a positive LRR of a lower TRP index transmitted in one dedicated periodic PUCCH resource of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is higher than that of a positive LRR of a higher TRP index transmitted in the other dedicated periodic PUCCH resource of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource. For example, assuming that the first dedicated periodic PUCCH resource is used to report the BFRQ (e.g., the first positive LRR) of a first TRP having a TRP index "1" , and the second dedicated periodic PUCCH resource is used to report the BFRQ (e.g., the second positive LRR) of a second TRP having a TRP index "2, " then the priority of a positive LRR transmitted in the second dedicated periodic PUCCH resource is lower than a priority of a positive LRR transmitted in first dedicated periodic PUCCH resource.

FIG. 7 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application with option 5 in case 1.

Referring to FIG. 7, the first TRP (e.g., TRP 1) and the second TRP (e.g., TRP 2) are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP 2. A first dedicated periodic PUCCH resource (e.g., PUCCH resource 1) is used to report the BFRQ of TRP 1 and is configured with beam 2 associated with TRP 2, and the second dedicated periodic PUCCH resource (e.g., PUCCH resource 2) is used to report the BFRQ of TRP 2 and is configured with beam 1 associated with TRP 1. PUCCH resource 1 may be also configured for SCell BFRQ. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 7, in transmission occasion t1, the UE may detect a beam failure of TRP 1 (e.g., the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold) , and may transmit a beam failure report of TRP 1 (e.g., a first positive LRR) in PUCCH resource 1 using beam 2 associated with TRP 2 in t2 to the BS. After transmitting the first positive LRR in t2, the UE may transmit a PUSCH carrying the MAC CE which includes a new beam indication of TRP 1 in t3. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resources) of TRP 1. Considering that all beams of TRP 1 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 2 as shown in FIG. 7 when the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In transmission occasion t4, the UE may detect a beam failure of TRP 2 (e.g., the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold) , and may transmit a beam failure report of TRP 2 (e.g., the second positive LRR) in the PUCCH resource 2 using beam 1 associated with TRP 1 in t5 to the BS. After transmitting the second positive LRR in t5, the UE may transmit a PUSCH carrying the MAC CE which includes a new beam indication of the TRP 2 in t6. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of TRP 2. Considering that all beams of TRP 2 failed, the PUSCH carrying the MAC CE may be transmitted to TRP 1 as shown in FIG. 7 if the PUSCH is transmitted in the PCell or in the PSCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in a SCell whose beam does not fail.

In transmission occasion t7, the UE may detect a beam failure of SCell (e.g., the radio link quality of all failure detection resources in the third set of failure detection resources is lower than the third threshold) , and may transmit a beam failure report of SCell (e.g., a third positive LRR) in the PUCCH resource 1 using beam 2 associated with TRP 2 in t8. Since the BS cannot distinguish the first positive LRR of TRP1 and the third positive LRR of SCell when receiving the LRR in PUCCH resource 1 in t8, it will schedule a PUSCH such that the UE may transmit the PUSCH carrying the MAC CE in t9 to TRP 2. The PUSCH carrying the MAC CE transmitted in t9 may indicate the failed beam (s) of the SCell and may include a new beam indication of the SCell. The new beam indication may indicate at least one new candidate beam (i.e., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in another SCell whose beam does not fail.

Option 6: Except for the first and second dedicated periodic PUCCH resources respectively configured for TRP specific BFRQ of the first and second TRP, another dedicated periodic PUCCH resource may be configured for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is different from both of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In an embodiment, the third dedicated periodic PUCCH resource may also be configured in a PCell or a PSCell. Since there are three dedicated periodic PUCCH resources in PCell or a PSCell, a priority between the dedicated periodic PUCCH resource for TRP specific BFRQ and that for SCell BFRQ should be determined. Considering the radio link quality of the PCell or PSCell is more important than SCell, in the case that the third dedicated periodic PUCCH resource and both of the first and the second dedicated periodic PUCCH resource are configured in the same PCell or PSCell, a priority of a positive LRR transmitted in any of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource. Besides, if there is possible that the first dedicated PUCCH resource and the second dedicate PUCCH resource may overlap with each other, then the priority of the positive LRR of a lower TRP index transmitted in one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is higher than the positive LRR of a higher TRP index transmitted in the other of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.

In another embodiment, the third dedicated periodic PUCCH resource may be configured in PUCCH-SCell, and the first dedicated periodic PUCCH resource for TRP specific BFRQ will not overlap with the third dedicated periodic PUCCH resource for SCell BFRQ due to being in different cells. Therefore, no priority is necessary to be determined for the dedicated periodic PUCCH resource for TRP specific BFRQ and that for SCell BFRQ.

FIG. 8 illustrates yet another exemplary procedure of LRR transmission according to some other embodiments of the present application with option 6 in case 1.

Referring to FIG. 8, the first TRP (e.g., TRP 1) and the second TRP (e.g., TRP 2) are deployed in a PCell or a PSCell. TRP 1 is configured with a first set of failure detection resource and TRP 2 is configured with a second set of failure detection resource. A first set of candidate resources may also be configured for TRP 1 and a second set of candidate resources may also be configured for TRP2. A first dedicated periodic PUCCH resource (e.g., PUCCH resource 1) is used to report the BFRQ of TRP 1 and is configured with beam 2 associated with TRP 2, and the second dedicated periodic PUCCH resource (e.g., PUCCH resource 2) is used to report the BFRQ of TRP 2 and is configured with beam 1 associated with TRP 1. PUCCH resource 3 may be configured for BFRQ of a SCell. A third set of failure detection resource and a third set of candidate resources may also be configured for the SCell.

As shown in FIG. 8, the steps performed before transmission occasion t7 are the same as those in FIG. 7, and will not repeat. In t7, when the UE detects that the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold (e.g., a beam failure for the SCell is detect) , the UE may transmit a beam failure report (i.e., a third positive LRR) of the SCell in PUCCH resource 3 in t8 to the BS. The UE may also transmit a PUSCH carrying the MAC CE which includes a new beam indication of the SCell in t9 in a PCell or a PSCell. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell. In another example, the PUSCH carrying the MAC CE may also be transmitted in another SCell whose beam does not fail.

In case 1, in some other embodiments, the first dedicated periodic PUCCH resource is configured in a PUCCH-SCell. In these embodiments, the first dedicated periodic PUCCH resource may be used to report the TRP specific BFRQs of the two TRPs.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold (e.g., all beams in the first set of failure detection resources are failed or a beam failure is detected for the first TRP) , the UE may transmit the first positive LRR in the first dedicated periodic PUCCH resource to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resource) of the first TRP (e.g., TRP 103a) to the BS.

In the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than the second threshold (e.g., all beams in the second set of failure detection resources are failed or a beam failure is detected for the second TRP) , the UE may transmit the second positive LRR in the first dedicated periodic PUCCH resource to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of the second TRP (e.g., the TRP 103b) to the BS.

Considering whether SCell BFRQ and TRP specific BFRQ are configured at the same time for the UE, there are two options, i.e., option 7 and option 8 regarding how to configure the dedicated periodic PUCCH resource for SCell BFRQ and TRP specific BFRQ.

Option 7: The dedicated periodic PUCCH resource configured for TRP specific BFRQ may be reused for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource. That is, the first dedicated periodic PUCCH resource is used to transmit the first LRR of the first TRP, the second LRR of the second TRP, and the third LRR of the SCell.

The UE may detect a beam failure of a SCell (e.g., the radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold) , and may transmit a beam failure report of SCell (e.g., a third positive LRR) in the first dedicated periodic PUCCH resource. After that, it will schedule a PUSCH such that the UE may transmit the PUSCH carrying the MAC CE after transmitting the third positive LRR. The PUSCH carrying the MAC CE may indicate the failed beam (s) of SCell and may include a new beam indication of the SCell. The new beam indication may indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell.

Option 8: Except for the first dedicated periodic PUCCH resource configured for TRP specific BFRQ of the first TRP and the second TRP, another dedicated periodic PUCCH resource may be configured for SCell BFRQ. In this option, the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource.

In an embodiment, the third dedicated periodic PUCCH resource may also be configured in a PUCCH-SCell. Since there are dedicated periodic PUCCH resources respectively for TRP specific BFRQ and SCell BFRQ in PUCCH-SCell, a priority between the dedicated periodic PUCCH resources respectively for TRP specific BFRQ and SCell BFRQ should be determined. Considering the radio link quality of the PCell or the PSCell is more important than SCell, when the first dedicated periodic PUCCH resource (or the second dedicated periodic PUCCH resource) and the third dedicated periodic PUCCH resource are configured in the same PUCCH-SCell, a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource (or the second dedicated periodic PUCCH resource) is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.

In another embodiment, the third dedicated periodic PUCCH resource may be configured in a PCell or a PSCell, and the first dedicated periodic PUCCH resource for TRP specific BFRQ will not overlap with the third dedicated periodic PUCCH resource for SCell BFRQ due to being in different cells. Therefore, no priority is necessary to be determined for the two dedicated periodic PUCCH resources.

Case 2

According to some other embodiments of the present application, the first set of failure detection resources and second set of failure detection resources may be configured in a SCell (hereinafter referred to as case 2) . In other words, case 2 means that two TRPs will be deployed in SCell in order to support TRP specific BFRQ of the two TRPs.

In some embodiments, one dedicated periodic PUCCH resource is shared for TRP specific BFRQ in SCell and SCell BFRQ. That is, the first dedicated periodic PUCCH resource may be used for two TRPs to report the TRP specific BFRQs and may also be reused for the SCell BFRQ. The first dedicated periodic PUCCH resource may be configured in a PCell, in a PSCell, or in a PUCCH-SCell.

In the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold (e.g., all beams in the first set of failure detection resources are failed or a beam failure is detected for the first TRP) , the UE 105 may transmit the first positive LRR in the first dedicated periodic PUCCH resource to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the first set of candidate resource) of the first TRP (e.g., the TRP 103a) to the BS.

In the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than the second threshold (e.g., all beams in the second set of failure detection resources are failed or a beam failure is detected for the second TRP) , the UE may transmit the second positive LRR in the first dedicated periodic PUCCH resource to the BS. The UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the second set of candidate resources) of the second TRP (e.g., the TRP 103b) to the BS.

In the case that the radio link quality of all failure detection resources in the third set of failure detection resources is lower than the third threshold (e.g., all beams in the third set of failure detection resources are failed or a beam failure is detected for SCell) , the UE may transmit the third positive LRR in the first dedicated periodic PUCCH resource to the BS. After that, the UE may further transmit a PUSCH carrying MAC CE to indicate at least one new candidate beam (e.g., at least one candidate resource in the third set of candidate resources) of the SCell to the BS.

FIG. 9 illustrates a simplified block diagram of an apparatus 900 for beam link recovery in multiple TRPs according to some embodiments of the present application. The apparatus 900 may be a BS 101 or a UE 105 (for example, UE 105a, UE 105b, or UE 105c) as shown in FIG. 1.

Referring to FIG. 9, the apparatus 900 may include at least one non-transitory computer-readable medium 902, at least one receiving circuitry 904, at least one transmitting circuitry 906, and at least one processor 908. In some embodiment of the present application, at least one receiving circuitry 904 and at least one transmitting circuitry 906 and be integrated into at least one transceiver. The at least one non-transitory computer-readable medium 902 may have computer executable instructions stored therein. The at least one processor 68 may be coupled to the at least one non-transitory computer-readable medium 902, the at least one receiving circuitry 904 and the at least one transmitting circuitry 906. The computer executable instructions can be programmed to implement a method with the at least one receiving circuitry 904, the at least one transmitting circuitry 906 and the at least one processor 908. The method can be a method according to an embodiment of the present application, for example, the method shown in FIG. 2.

The method according to embodiments of the present application can also be implemented on a programmed processor. However, the controllers, flowcharts, and modules may also be implemented on a general purpose or special purpose computer, a programmed microprocessor or microcontroller and peripheral integrated circuit elements, an integrated circuit, a hardware electronic or logic circuit such as a discrete element circuit, a programmable logic device, or the like. In general, any device on which resides a finite state machine capable of implementing the flowcharts shown in the figures may be used to implement the processor functions of this application. For example, an embodiment of the present application provides an apparatus for beam failure recovery in multiple TRPs, including a processor and a memory. Computer programmable instructions for implementing a method for beam failure recovery in multiple TRPs are stored in the memory, and the processor is configured to perform the computer programmable instructions to implement the method for beam failure recovery. The method may be a method as stated above or other method according to an embodiment of the present application.

An alternative embodiment preferably implements the methods according to embodiments of the present application in a non-transitory, computer-readable storage medium storing computer programmable instructions. The instructions are preferably executed by computer-executable components preferably integrated with a network security system. The non-transitory, computer-readable storage medium may be stored on any suitable computer readable media such as RAMs, ROMs, flash memory, EEPROMs, optical storage devices (CD or DVD) , hard drives, floppy drives, or any suitable device. The computer-executable component is preferably a processor but the instructions may alternatively or additionally be executed by any suitable dedicated hardware device. For example, an embodiment of the present application provides a non-transitory, computer-readable storage medium having computer programmable instructions stored therein. The computer programmable instructions are configured to implement a method for beam failure recovery as stated above or other method according to an embodiment of the present application.

While this application has been described with specific embodiments thereof, it is evident that many alternatives, modifications, and variations may be apparent to those skilled in the art. For example, various components of the embodiments may be interchanged, added, or substituted in the other embodiments. Also, all of the elements of each figure are not necessary for operation of the disclosed embodiments. For example, one of ordinary skill in the art of the disclosed embodiments would be enabled to make and use the teachings of the application by simply employing the elements of the independent claims. Accordingly, embodiments of the application as set forth herein are intended to be illustrative, not limiting. Various changes may be made without departing from the spirit and scope of the application.

Claims

A method, comprising:

receiving configuration information indicating:

at least one set of failure detection resources, at least comprising: a first set of failure detection resource associated with a first transmit-receive point (TRP) index, a second set of failure detection resources associated with a second TRP index, and a third set of failure detection resources associated with a secondary cell (SCell) ; and

a set of dedicated periodic physical uplink control channel (PUCCH) resources;

in the case that a radio link quality of all failure detection resources in the first set of failure detection resources is lower than a first threshold, transmitting a first positive link recovery request (LRR) in a first dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources; and

in the case that a radio link quality of all failure detection resources in the third set of failure detection resources is lower than a third threshold, transmitting a third positive LRR in a third dedicated periodic PUCCH resource of the set of dedicated periodic PUCCH resources, wherein the first dedicated periodic PUCCH resource and third dedicated periodic PUCCH resource are the same or different.
The method of claim 1, wherein the first set of failure detection resources and second set of failure detection resources are configured in a primary cell (PCell) or a primary secondary cell (PSCell) .
The method of claim 2, wherein the first dedicated periodic PUCCH resource is a dedicated periodic PUCCH resource in the PCell or the PSCell.
The method of claim 3, wherein the first dedicated periodic PUCCH resource is configured with two spatial relation information and is configured with a beam mapping pattern to indicate which spatial relation information is used in each transmission occasion of the first dedicated periodic PUCCH resource, and the method comprises:

in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using second spatial relation information associated with the second TRP index; and

in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in a transmission occasion of the first dedicated periodic PUCCH resource using first spatial relation information associated with the first TRP index.
The method of claim 4, wherein the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource.
The method of claim 4, wherein the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource, and wherein a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in a same PCell or PSCell.
The method of claim 3, comprising:

in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in the first dedicated periodic PUCCH resource with second spatial relation information associated with the second TRP index; and

in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a physical uplink shared channel (PUSCH) carrying a medium access control (MAC) control element (CE) to indicate that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, wherein a PUSCH resource for transmitting the PUSCH is requested by a scheduling request (SR) transmitted in a PUCCH resource configured by a radio resource control (RRC) signaling.
The method of claim 7, wherein the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource.
The method of claim 7, wherein the third dedicated periodic PUCCH resource is different from the first dedicated periodic PUCCH resource, and wherein a priority of a positive LRR transmitted in the first dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource when the first dedicated periodic PUCCH resource and the third dedicated periodic PUCCH resource are configured in a same PCell or PSCell.
The method of claim 3, wherein the set of dedicated periodic PUCCH resources further comprise a second dedicated periodic PUCCH resource in the PCell or the PSCell, and the method further comprises:

in the case that the radio link quality of all failure detection resources in the first set of failure detection resources is lower than the first threshold, transmitting the first positive LRR in the first dedicated periodic PUCCH resource with second spatial relation information associated with the second TRP index; and

in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in the second dedicated periodic PUCCH resource with first spatial relation information associated with the first TRP index.
The method of claim 10, wherein the third dedicated periodic PUCCH resource is the same as one of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource.
The method of claim 10, wherein,

the third dedicated periodic PUCCH resource is different from any of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource; and

in the case that the third dedicated periodic PUCCH resource and both of the first and the second dedicated periodic PUCCH resource are configured in a same PCell or PSCell, a priority of a positive LRR transmitted in any of the first dedicated periodic PUCCH resource and the second dedicated periodic PUCCH resource is higher than that of a positive LRR transmitted in the third dedicated periodic PUCCH resource.
The method of claim 2, wherein the first dedicated periodic PUCCH resource is configured in a PUCCH-SCell, wherein the third dedicated periodic PUCCH resource is the same as the first dedicated periodic PUCCH resource, and the method further comprises:

in the case that the radio link quality of all failure detection resources in the second set of failure detection resources is lower than a second threshold, transmitting a second positive LRR in the first dedicated periodic PUCCH resource.
The method of claim 1, wherein the first set of failure detection resources and second set of failure detection resources are configured in a SCell, wherein the first dedicated periodic PUCCH resource is the same as the third dedicated periodic PUCCH resource, and the method comprises:

in the case that radio link quality of all failure detection resources in the second set of failure detection resources are lower than a second threshold, transmitting a second positive LRR in the first dedicated periodic PUCCH resource.
The method of claim 1, wherein the TRP index is one of the following:

a CORESETPoolIndex value;

a failure detection resource set index;

a candidate resource set index; and

a RRC configured index other than a CORESETPoolIndex value, a failure detection resource set index, and a candidate resource set index.