Determining phase tracking reference signals in multiple transmission points

Patent metadata

Field	Value
Publication number	US-2021143964-A1
Application number	US-202017106684-A
Country	US
Kind code	A1
Filing date	Nov 30, 2020
Priority date	Nov 8, 2019
Publication date	May 13, 2021
Grant date	—

Abstract

A method for a UE in a multiple transmission points communication system, mTRP, scheme, is provided. The method includes receiving downlink control information, DCI, indicating a at least two transmission points scheme for a scheduled data transmission on physical resource blocks, PRBs. The PRBs includes at least a first subsets of PRBs, associated with a first transmission point, and a second subset of PRBs, associated with a second transmission point. The method further includes determining a first PT-RS frequency density for the first set of PRBs based on the number of PRBs in the first set of PRBs and a second PT-RS frequency density based on the number of PRBs in the second set of PRBs. A UE, methods for a base station and a base station are also provided.

First claim

1 . A method for a UE ( 1200 ) in a multiple transmission points communication system, mTRP, the method comprising:
receiving ( 1501 ) a higher layer configuration of a mTRP scheme; receiving ( 1503 ) downlink control information, DCI, indicating a first and a second Transmission Configuration Indicator, TCI, state in one Code Division Multiplexing, CDM, group for a scheduled data transmission on physical resource blocks, PRBs, wherein the PRBs comprise at least a first subset of PRBs, associated with the first TCI state, and a second subset of PRBs, associated with the second TCI state; and determining ( 1505 ) a first Phase Tracking Reference Signal, PT-RS, frequency density for the first subset of PRBs based on the number of PRBs in the first subset of PRBs and a second PT-RS frequency density for the second subset of PRBs based on the number of PRBs in the second subset of PRBs.

2 . A method according to claim 1 , wherein the first TCI state is associated with a first transmission point in the multiple transmission points communication system and wherein the second TCI state is associated with the second transmission point the multiple transmission points communication system.

3 . A method according to claim 1 , wherein the PT-RS to resource element mapping is associated to the allocated PRBs for each TCI state.

4 . A method according to claim 1 , wherein the data transmission comprises one or more physical downlink share channel, PDSCH, transmissions scheduled by the DCI.

5 . A method according to claim 1 , wherein the first PT-RS frequency density and the second PT-RS frequency density are determined for the same PT-RS port.

6 . A method according to claim 5 , wherein the mTRP scheme is one of a FDM Scheme 2a, wherein a single PDSCH transmission for a transport block, TB, is scheduled across the first and the second subsets of PRBs, or a FDM Scheme 2b, wherein a first PDSCH transmission for a TB is scheduled in the first subsets of PRBs and a second PDSCH transmission for the same TB is scheduled in the second subsets of PRBs.

7 . A method according to claim 1 wherein the at least two subsets are non-overlapping.

8 . A UE ( 1200 ) operable in a multiple transmission points communication system, mTRP, the UE comprising a transceiver ( 1201 ) and processing circuitry ( 1203 ) configured to:
receive a higher layer configuration of a mTRP scheme; receive downlink control information, DCI, indicating a first and a second Transmission Configuration Indicator, TCI, state in one Code Division Multiplexing, CDM, group for a scheduled data transmission on physical resource blocks, PRB s, wherein the PRBs comprise at least a first subset of PRBs, associated with the first TCI state, and a second subset of PRBs, associated with the second TCI state; and determine a first Phase Tracking Reference Signal, PT-RS, frequency density for the first subset of PRBs based on the number of PRBs in the first subset of PRBs and a second PT-RS frequency density for the second subset of PRBs based on the number of PRBs in the second subset of PRBs.

9 . A UE according to claim 8 , wherein the first TCI state is associated with a first transmission point in the multiple transmission points communication system and wherein the second TCI state is associated with the second transmission point the multiple transmission points communication system.

10 . A UE according to claim 8 , wherein the PT-RS to resource element mapping is associated to the allocated PRBs for each TCI state.

11 . A UE according to claim 8 , wherein the data transmission comprises one or more physical downlink share channel, PDSCH, transmissions scheduled by the DCI.

12 . A UE according to claim 8 , wherein the first PT-RS frequency density and the second PT-RS frequency density are determined for the same PT-RS port.

13 . A UE according to claim 12 , wherein the mTRP scheme is one of a FDM Scheme 2a, wherein a single PDSCH transmission for a transport block, TB, is scheduled across the first and the second subsets of PRBs, or a FDM Scheme 2b, wherein a first PDSCH transmission for a TB is scheduled in the first subsets of PRBs and a second PDSCH transmission for the same TB is scheduled in the second subsets of PRBs.

14 . A UE according to claim 8 , wherein the at least two subsets are non-overlapping.

15 . A method for a base station ( 1300 ) in a multiple transmission points communication system, mTRP, scheme, the method comprising:
transmitting ( 1601 ) a higher layer configuration of a mTRP scheme; transmitting ( 1603 ) downlink control information, DCI, indicating a first and a second Transmission Configuration Indicator, TCI, state in one Code Division Multiplexing, CDM, group for a scheduled data transmission on physical resource blocks, PRBs, wherein the PRBs comprise at least a first subset of PRBs, associated with the first TCI state, and a second subset of PRBs, associated with the second TCI state; and wherein a first PT-RS frequency density for the first set of PRBs is obtainable based on the number of PRBs in the first set of PRBs and a second PT-RS frequency density for the second set of PRBs is obtainable based on the number of PRBs in the second set of PRBs.

16 . A method according to claim 15 , wherein the first TCI state is associated with a first transmission point in the multiple transmission points communication system and wherein the second TCI state is associated with the second transmission point the multiple transmission points communication system.

17 . A method according to claim 15 , wherein the PT-RS to resource element mapping is associated to the allocated PRBs for each TCI state.

18 . A method according to claim 15 , wherein the data transmission comprises one or more physical downlink share channel, PDSCH, transmissions scheduled by the DCI.

19 . A method according to claim 15 , wherein the first PT-RS frequency density and the second PT-RS frequency density are determined for the same PT-RS port.

20 . A method according to claim 19 , wherein the mTRP scheme is one of a FDM Scheme 2a, wherein a single PDSCH transmission for a transport block, TB, is scheduled across the first and the second subsets of PRBs, or a FDM Scheme 2b, wherein a first PDSCH transmission for a TB is scheduled in the first subsets of PRBs and a second PDSCH transmission for the same TB is scheduled in the second subsets of PRBs.

21 . A method according to claim 15 wherein the at least two subsets are non-overlapping.

22 . A base station ( 1300 ) operable in a multiple transmission points communication system, mTRP, scheme, the base station comprising a transceiver ( 1301 ) and processing circuitry ( 1303 ) configured to:
transmit a higher layer configuration of a mTRP scheme; transmit downlink control information, DCI, indicating a first and a second Transmission Configuration Indicator, TCI, state in one Code Division Multiplexing, CDM, group for a scheduled data transmission on physical resource blocks, PRBs, wherein the PRBs comprise at least a first subset of PRBs, associated with the first TCI state, and a second subset of PRBs, associated with the second TCI state; and wherein a first PT-RS frequency density for the first set of PRBs is obtainable based on the number of PRBs in the first set of PRBs and a second PT-RS frequency density for the second set of PRBs is obtainable based on the number of PRBs in the second set of PRBs.

23 . A base station according to claim

Assignees

• Ericsson Telefon Ab L M

Inventors

• Frenne Mattias
• Gao Shiwei
• Muruganathan Siva

Classifications

• H04W72/23

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

• H04W72/1273

  of downlink data flows · CPC title

• H04W72/232

  the control data signalling from the physical layer, e.g. DCI signalling · CPC title

• H04L5/0048 Primary

  Allocation of pilot signals, i.e. of signals known to the receiver (allocation of control signalling H04L5/0053; use of control signalling H04L5/0091) · CPC title

• H04L5/0023

  Time-frequency-space · CPC title