Method and apparatus for beam failure reporting under multicell configuration in a wireless communication system

{
  "publication_number": "US10893431B2",
  "country": "US",
  "kind": "B2",
  "title": "Method and apparatus for beam failure reporting under multicell configuration in a wireless communication system",
  "abstract": "A method and apparatus are disclosed from the perspective of a User Equipment (UE). In one embodiment, the method includes the UE being served and/or configured with a first cell and a second cell. The method also includes the UE transmitting a beam failure recovery request via a PRACH (Physical Random Access Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the second cell have failed. Furthermore, the method includes the UE transmitting a first report via a PUCCH (Physical Uplink Control Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the first cell have failed.",
  "claims": [
    "1. A method for a UE (User Equipment), comprising: the UE is served and/or configured with a first cell and a second cell by a network; the UE transmits a beam failure recovery request via a PRACH (Physical Random Access Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the second cell have failed, and the UE transmits a first report via a PUCCH (Physical Uplink Control Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the first cell have failed.",
    "2. The method of claim 1, wherein the UE does not transmit a request or a preamble on PRACH resource in response to the UE detecting all links associated with monitored control resource set(s) in the first cell have failed.",
    "3. The method of claim 1, wherein the first cell is a secondary cell and the second cell is a primary cell.",
    "4. The method of claim 1, wherein the first report comprises a resource index related to a candidate link, wherein the resource index is a reference signal resource index, and the reference signal resource index comprises CSI-RS (Channel State Information Reference Signal) index and/or SSB (Synchronization Signal Block) index; or wherein the first report comprises at least an index related to the failed links and a quality value related to the failed links.",
    "5. The method of claim 1, wherein the first report includes a beam failure report transmitted via the PUCCH, or wherein the PUCCH is used for beam failure recovery request transmission.",
    "6. The method of claim 1, wherein the UE keeps connecting with the network via at least the second cell.",
    "7. The method of claim 1, wherein the UE transmits a second report when at least one link associated with monitored control resource set in the first cell has not failed, and the second report is for normal beam reporting for reporting measured quality of downlink reference signals.",
    "8. The method of claim 7, wherein the UE does not transmit the second report when all links associated with monitored control resource set(s) in the first cell has failed.",
    "9. The method of claim 7, wherein the first report and the second report have the same format structure, and the format structure is related to one or more of the followings: a bit width or length of the index, a bit width or length of the quality value, or a number of reported links.",
    "10. The method of claim 1, wherein a link is a connection between the UE and the network, and the link fails when the quality of the connection, which is RSRP (Radio Resource Control) or BLER (Block Error Rate) derived by the UE, falls below a threshold.",
    "11. The method of claim 1, wherein an antenna port for receiving downlink transmission in the first cell is QCLed (Quasi Co-Located) with that for receiving downlink reference signal resources transmitted in the second cell.",
    "12. A User Equipment (UE) wherein the UE is served and/or configured with a first cell and a second cell, comprising: a control circuit; a processor installed in the control circuit; and a memory installed in the control circuit and operatively coupled to the processor; wherein the processor is configured to execute a program code stored in the memory to: transmit a beam failure recovery request via a PRACH (Physical Random Access Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the second cell have failed, and transmit a first report via a PUCCH (Physical Uplink Control Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the first cell have failed.",
    "13. The UE of claim 12, wherein the UE does not transmit a request or a preamble on PRACH resource if all links associated with monitored control resource set(s) in the first cell have failed.",
    "14. The UE of claim 12, wherein the first cell is a secondary cell and the second cell is a primary cell.",
    "15. The UE of claim 12, wherein the first report comprises a resource index related to a candidate link, wherein the resource index is a reference signal resource index, and the reference signal resource index comprises CSI-RS (Channel State Information Reference Signal) index and/or SSB (Synchronization Signal Block) index; or wherein the first report comprises at least an index related to the failed links and a quality value related to the failed links.",
    "16. The UE of claim 12, wherein the first report includes a beam failure report transmitted via the PUCCH, or wherein the PUCCH is used for beam failure recovery request transmission.",
    "17. The UE of claim 12, wherein the UE keeps connecting with network via at least the second cell.",
    "18. The UE of claim 12, wherein the UE transmits a second report when at least one link associated with monitored control resource set in the first cell has not failed, and the second report is for normal beam reporting for reporting measured quality of downlink reference signals, and wherein the first report and a second report have the same format structure, and the format structure is related to one or more of the followings: a bit width or length of the index, a bit width or length of the quality value, or a number of reported links.",
    "19. The UE of claim 12, wherein a link is a connection between the UE and the network, and the link fails when the quality of the connection, which is RSRP (Radio Resource Control) or BLER (Block Error Rate) derived by the UE, falls below a threshold.",
    "20. The UE of claim 12, wherein an antenna port for receiving downlink transmission in the first cell is QCLed (Quasi Co-Located) with downlink reference signal resources transmitted in the second cell."
  ],
  "description_excerpt": "This disclosure generally relates to wireless communication networks, and more particularly, to a method and apparatus for beam failure reporting under multicell configuration in a wireless communication system.\n\nWith the rapid rise in demand for communication of large amounts of data to and from mobile communication devices, traditional mobile voice communication networks are evolving into networks that communicate with Internet Protocol (IP) data packets. Such IP data packet communication can provide users of mobile communication devices with voice over IP, multimedia, multicast and on-demand communication services.\n\nAn exemplary network structure is an Evolved Universal Terrestrial Radio Access Network (E-UTRAN). The E-UTRAN system can provide high data throughput in order to realize the above-noted voice over IP and multimedia services. A new radio technology for the next generation (e.g., 5G) is currently being discussed by the 3GPP standards organization. Accordingly, changes to the current body of 3GPP standard are currently being submitted and considered to evolve and finalize the 3GPP standard.\n\nA method and apparatus are disclosed from the perspective of an User Equipment (UE). In one embodiment, the method includes the UE being served and/or configured with a first cell and a second cell. The method also includes the UE transmitting a beam failure recovery request via a PRACH (Physical Random Access Channel) in the second cell in response to the UE detecting that all links associated with monitored control resource set(s) in the second cell have failed.",
  "cpc": [
    "H04W 24/10",
    "H04W 16/28",
    "H04W 24/02",
    "H04W 72/046",
    "H04W 74/002",
    "H04W 74/0833",
    "H04W 74/0866",
    "H04W 76/19"
  ],
  "ipc": [
    "H04W 16/28",
    "H04W 24/10"
  ],
  "assignees": [
    "Asustek Computer Inc"
  ],
  "inventors": [
    "Jia-Hong Liou",
    "Ming-Che Li"
  ],
  "filing_date": "2019-01-18",
  "publication_date": "2021-01-12",
  "grant_date": "2021-01-12",
  "priority_date": "2018-01-19",
  "application_number": "US-201916251843-A",
  "family_id": "67300363",
  "cited_by_count": 40,
  "citations": [
    "US20170055191A1",
    "WO2018147665A1",
    "US20180288645A1",
    "US20190132066A1",
    "WO2019135654A1",
    "US20190215048A1",
    "US20190253949A1"
  ]
}