Repetition of PRACH preamble transmission for UEs

Patent metadata

Field	Value
Publication number	US-11310836-B2
Application number	US-202016947575-A
Country	US
Kind code	B2
Filing date	Aug 6, 2020
Priority date	Aug 19, 2019
Publication date	Apr 19, 2022
Grant date	Apr 19, 2022

Abstract

Apparatuses and methods for physical random access channel (PRACH) preamble transmissions or receptions. A method of a UE includes receiving a physical downlink shared channel (PDSCH) that provides a system information block (SIB). The SIB includes an indication for (i) a first transmission configuration indication (TCI) state that provides a first set of quasi-collocation (QCL) properties and (ii) for a second TCI state that provides a second set of QCL properties. The method further includes transmitting a first PRACH according to the first TCI state and a second PRACH according to the second TCI state.

First claim

What is claimed is:

1. A method comprising:
receiving a physical downlink shared channel (PDSCH) that provides a system information block (SIB), wherein the SIB includes an indication for (i) a first transmission configuration indication (TCI) state that provides a first set of quasi-collocation (QCL) properties and (ii) for a second TCI state that provides a second set of QCL properties; and
transmitting a first physical random access channel (PRACH) according to the first TCI state and a second PRACH according to the second TCI state.

2. The method of claim 1 , further comprising:
receiving a synchronization signal and broadcast channel block;
measuring a reference signal received power (RSRP) value based on the synchronization signal and broadcast channel block; and
determining to transmit the first PRACH according to the first TCI state and the second PRACH according to the second TCI state based on the RSRP value being smaller than an RSRP threshold,
wherein the RSRP threshold is included in the SIB.

3. The method of claim 1 , wherein:
transmitting the second PRACH comprises transmitting the second PRACH with a number of repetitions, and
the number of repetitions is included in the SIB.

4. The method of claim 1 , wherein the first PRACH transmission is from a first antenna port and the second PRACH transmission is from a second antenna port.

5. The method of claim 1 , further comprising:
receiving:
at least one of a first physical downlink control channel (PDCCH) according to the first TCI state and a second PDCCH according to the second TCI state, wherein the first PDCCH schedules a reception of a first PDSCH and the second PDCCH schedules a reception of a second PDSCH; and
the first PDSCH according to the first TCI state or the second PDSCH according to the second TCI state, wherein the received first PDSCH or second PDSCH includes a random access response (RAR) message in response to the first PRACH transmission or the second PRACH transmission.

6. The method of claim 5 , further comprising:
transmitting a physical uplink shared channel (PUSCH) that is scheduled by information in the RAR message, wherein the PUSCH transmission is according to the first TCI state when the RAR message is included in the first PDSCH or the second TCI state when the RAR message is included in the second PDSCH.

7. The method of claim 5 , further comprising:
receiving the first PDCCH from a first antenna port and the second PDCCH from a second antenna port.

8. A user equipment (UE) comprising:
a transceiver configured to:
receive a physical downlink shared channel (PDSCH) that provides a system information block (SIB), wherein the SIB includes an indication for (i) a first transmission configuration indication (TCI) state that provides a first set of quasi-collocation (QCL) properties and (ii) for a second TCI state that provides a second set of QCL properties; and
transmit a first physical random access channel (PRACH) according to the first TCI state and a second PRACH according to the second TCI state.

9. The UE of claim 8 , wherein the transceiver is further configured to receive a synchronization signal and broadcast channel block, the UE further comprising:
a processor configured to:
measure a reference signal received power (RSRP) value based on a synchronization signal and broadcast channel block; and
determine to transmit the first PRACH according to the first TCI state and the second PRACH according to the second TCI state based on the RSRP value being smaller than an RSRP threshold,

wherein the RSRP threshold is included in the SIB.

10. The UE of claim 8 , wherein:
the transceiver is configured to transmit the second PRACH with a number of repetitions, and
the number of repetitions is included in the SIB.

11. The UE of claim 8 , wherein the first PRACH transmission is from a first antenna port and the second PRACH transmission is from a second antenna port.

12. The UE of claim 8 , wherein the transceiver is further configured to receive:
at least one of a first physical downlink control channel (PDCCH) according to the first TCI state and a second PDCCH according to the second TCI state, wherein the first PDCCH schedules a reception of a first PDSCH and the second PDCCH schedules a reception of a second PDSCH; and
the first PDSCH according to the first TCI state or the second PDSCH according to the second TCI state, wherein the received first PDSCH or second PDSCH includes a random access response (RAR) message in response to the first PRACH transmission or the second PRACH transmission.

13. The UE of claim 12 , wherein:
the transceiver is further configured to transmit a physical uplink shared channel (PUSCH) that is scheduled by information in the RAR message, and
the PUSCH transmission is according to the first TCI state when the RAR message is included in the first PDSCH or the second TCI state when the RAR message is included in the second PDSCH.

14. The UE of claim 12 , wherein the transceiver is further configured to receive the first PDCCH from a first antenna port and the second PDCCH from a second antenna port.

15. A base station comprising:
a transceiver configured to:
transmit a physical downlink shared channel (PDSCH) that provides a system information block (SIB), wherein the SIB includes an indication for (i) a first transmission configuration indication (TCI) state that provides a first set of quasi-collocation (QCL) properties and (ii) for a second TCI state that provides a second set of QCL properties; and
receive a first physical random access channel (PRACH) according to the first TCI state and a second PRACH according to the second TCI state.

16. The base station of claim 15 , wherein:
the transceiver is further configured to receive the second PRACH with a number of repetitions, and
the number of repetitions is included in the SIB.

17. The base station of claim 15 , wherein the first PRACH reception is by a first antenna port and the second PRACH reception is by a second antenna port.

18. The base station of claim 15 , wherein the transceiver is further configured to transmit:
at least one of a first physical downlink control channel (PDCCH) according to the first TCI state and a second PDCCH according to the second TCI state, wherein the first PDCCH schedules a reception of a first PDSCH and the second PDCCH schedules a reception of a second PDSCH; and
the first PDSCH according to the first TCI state or the second PDSCH according to the second TCI state, wherein the transmitted first PDSCH or second PDSCH includes a random access response (RAR) message in response to the first PRACH reception or the second PRACH reception.

19. The base station of claim 18 , wherein:
the transceiver is further configured to receive a physical uplink shared channel (PUSCH) that is scheduled by information in the RAR message, and
the PUSCH reception is according to the first TCI state when the RAR message is included in the first PDSCH or the second TCI state when the RAR message is included in the second PDSCH.

20. The base station of claim 18 , wherein the transceiver is further configured to transmit the first PDCCH from a first antenna port and the second PDCCH from a second antenna port.

Assignees

• Samsung Electronics Co Ltd

Inventors

• Molavianjazi Ebrahim
• Papasakellariou Aris

Classifications

• H04W74/0833 Primary

  Random access procedures, e.g. with 4-step access · CPC title

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W74/0836

  with 2-step access · CPC title

• H04W74/0838

  using contention-free random access [CFRA] · CPC title

• H04L5/0094

  Indication of how sub-channels of the path are allocated · CPC title