SRS Configuration and Indication for Codebook and Non-Codebook Based UL Transmissions in a Network

Patent metadata

Field	Value
Publication number	US-2022123799-A1
Application number	US-202017428213-A
Country	US
Kind code	A1
Filing date	Feb 14, 2020
Priority date	Feb 16, 2019
Publication date	Apr 21, 2022
Grant date	—

Abstract

The embodiments herein relate to a method performed by a network node and a network node. The method comprises setting a higher-layer parameter usage in at least one sounding reference signal, SRS, resource set configuration to nonCodebook or Codebook, wherein each configured SRS resource set comprises one or more SRS resources, and scheduling a physical uplink shared channel (PUSCH) transmission via a downlink control information (DCI) wherein at least two SRS resources are indicated via a sounding reference signal resource indicator (SRI) field of the DCI, wherein each SRS resource is associated with a different SRS resource set; and receiving from the user equipment a physical uplink shared channel that is transmitted using the ports associated with the indicated SRS resources.

First claim

1 - 22 . (canceled)

23 . A method performed by a network node, the method comprising:
configuring at least two sounding reference signal (SRS) resource sets for a user equipment via a higher layer, wherein each SRS resource set comprises at least one SRS resource, and wherein the higher layer configuration of the SRS comprises a parameter usage and the value of the parameter is set to nonCodebook or Codebook; scheduling at least one physical uplink shared channel (PUSCH) transmission for said user equipment via a downlink control information (DCI) wherein at least two SRS resources are indicated via a sounding reference signal resource indicator (SRI) field of the DCI, wherein each SRS resource is associated with a different SRS resource set; mapping a given SRI bit field of the SRI field to the SRS resources indicated from associated SRS resource sets; and receiving from the user equipment a PUSCH that is transmitted using antenna ports associated with the indicated SRS resources,
wherein, in the case when the usage is set to codebook, the DCI indicates as many transmitted precoding matrix index (TPMI) values as the number of SRS resources indicated via the SRI field of the DCI in which a first TPMI value indicates the precoder for the antenna ports corresponding to a first SRS resource and a second TPMI value indicates the precoder for the antenna ports corresponding to a second SRS resource and so on, and
wherein, in the case when the usage is set to nonCodebook, each SRS resource in the SRS resource set configuration is configured with only one port, and wherein each SRS port has a one-to-one mapping with a demodulation reference signal (DMRS) port and thereby, a transmission layer associated with said PUSCH.

24 . The method according to claim 23 , wherein the higher-layer parameter is set in said at least SRS resource set configuration to nonCodebook or Codebook, and wherein any two SRS resources configured for two different SRS resource sets, having the same time domain behavior which includes one of the following: aperiodic, semi-persistent or periodic, can be transmitted simultaneously by the user equipment (UE).

25 . The method according to claim 23 , wherein the maximum number of SRS resource sets supported by the UE for codebook and non-codebook-based uplink transmission, is a UE capability that is reported to said network node by said UE via a higher-layer message, for e.g., radio resource control (RRC) and wherein the value of the UE capability is identical to the number of either all of UE panels/Tx-Rx RF chains, or a subset of UE panels/Tx-Rx RF chains.

26 . The method according to claim 23 , wherein in the case of aperiodic SRS transmission, reference SRS resource sets are the SRS resource sets transmitted after the most recent downlink control information (DCI) carrying a SRS request triggering the aperiodic resource sets, wherein the reference SRS resource set(s) with respect to an SRI field are defined as the SRS resource set(s) from which the SRS resource(s) are indicated by the SRI field.

27 . The method according to claim 23 , wherein in the case of semi-persistent SRS transmission, reference SRS resource sets for a SRI of the PUSCH-scheduling DCI in transmission slot n are all the semi-persistent SRS resource sets that were not deactivated by a medium access control (MAC) control element command before n-k slots, where k is a constant value, wherein the reference SRS resource set(s) with respect to an SRI field are defined as the SRS resource set(s) from which the SRS resource(s) are indicated by the SRI field.

28 . The method according to claim 23 , wherein in the case of periodic SRS transmission, reference SRS resource sets are the periodic SRS resource sets configured by the higher-layer for a (BWP) bandwidth-part, associated with the DCI, wherein the reference SRS resource set(s) with respect to an SRI field are defined as the SRS resource set(s) from which the SRS resource(s) are indicated by the SRI field.

29 . The method according to claim 23 , wherein, only the SRS resources that belong to reference SRS resource set(s) is/are indicated in the SRI field of the PUSCH-scheduling DCI, wherein the reference SRS resource set(s) with respect to an SRI field are defined as the SRS resource set(s) from which the SRS resource(s) are indicated by the SRI field.

30 . The method according to claim 23 , wherein said mapping is performed using the following table:

SRS resource(s)

SRS resource(s)

SRI Bit
indicated for NCB
SRI Bit
indicated for

field
(L max (NCB) = 1)
field
(L max (NCB) = 1)

mapped to
and CB UL
mapped to
and CB UL

index
(N max, SRSres (CB) = 1)
index
(N max, SRSres (CB) = 2)

0
S 0 0
0
S 0 0

1
S 0 1
1
S 0 1

2
S 0 0 ,

S 0 1

3
reserved

wherein the notation s i j denotes the i-th SRS resource of the j-th reference SRS resource set, wherein L max (NCB) is the value of the UE capability parameter ‘maxNumberMIMO-LayersNonCB-PUSCH’ defined in 3GPP Rel. 15, and for non-codebook based SRS, the values of i and j are given by i=0, . . . , N SRSres (NCB) −1 and j=0, . . . , N SRSset,Tx (NCB) −1, respectively, wherein N SRSset,Tx (NCB) is the number of reference SRS resource sets, wherein for codebook-based SRS, the values of i and j are given by i=0, . . . , N SRSres (CB) −1 and j=0, . . . , N SRSset,Tx (CB) −1, respectively, wherein N SRSset,Tx (CB) is the number of reference SRS resource sets.

31 . The method according to claim 23 , wherein said mapping is performed using the following table:

SRS resource(s)

SRS resource(s)

SRI Bit
indicated for NCB
SRI Bit
indicated for NCB

field
(L max (NCB) = 1)
field
(L max (NCB) = 2)

mapped to

Assignees

• Fraunhofer Ges Forschung

Inventors

• Varatharaajan Sutharshun
• Grossmann Marcus
• Landmann Markus

Classifications

• H04W72/23

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

• H04B7/0456 Primary

  Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting · CPC title

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• H04L25/0224

  using sounding signals · CPC title

• H04L5/0094

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