Search

US-12627441-B2 - SRS sounding procedure for positioning

US12627441B2US 12627441 B2US12627441 B2US 12627441B2US-12627441-B2

Abstract

A user equipment (UE) configured for operating in a wireless communication network that supports a plurality of reference signals (RS) such as sounding reference signals, comprises a wireless interface configured for transceiving signals, comprising receiving a configuration signal having a configuration information indicating a reference spatial relation. The UE further comprises a controller for evaluating the configuration information and to determine the reference spatial relation. The UE is configured for using the reference spatial relation as a reference for an uplink RS (UL-RS) in the wireless communication network.

Inventors

  • Mohammad ALAWIEH
  • Birendra Ghimire
  • Ernst Eberlein
  • NORBERT FRANKE
  • Mohammad MOMANI

Assignees

  • Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.

Dates

Publication Date
20260512
Application Date
20230131
Priority Date
20200806

Claims (18)

  1. 1 . A user equipment (UE) configured for operating in a wireless communication network that supports a plurality of reference signals (RS), the UE comprising: a wireless interface configured for transceiving signals, comprising receiving a configuration signal having a configuration information indicating a reference spatial relation and a spatial relation; a controller for evaluating the configuration information and to determine the reference spatial relation; wherein the UE is configured for using the reference spatial relation as a reference for an uplink RS (UL-RS) in the wireless communication network using the spatial relation for an uplink RS (UL-RS) transmission, and, in a case when the spatial relation is not configured, using the reference spatial relation comprising a default beam configuration to activate a spatial TX filter for the UL-RS transmission based on a channel condition.
  2. 2 . The UE of claim 1 , wherein the UE is configured to assume the reference spatial relation as an Rx spatial filter acquired from an SS/PBCH block of a serving cell that the UE uses to acquire MIB in a case when the reference spatial relation is not configured.
  3. 3 . The UE of claim 1 , wherein the reference spatial relation is providing a reference for the target UL-RS transmission and unlike spatialRelationInfo, the UE is not expected to transmit target UL-RS within the spatial filter information of the reference RS.
  4. 4 . The UE of claim 1 , wherein the UE is configured to assume the reference spatial relation as an Rx spatial filter acquired from an SS/PBCH block of a serving cell that the UE uses to acquire MIB in a case when the reference spatial relation is not configured; and wherein the reference spatial relation is providing a reference for the target UL-RS transmission and unlike spatialRelationInfo, the UE is not expected to transmit target UL-RS within the spatial filter information of the reference RS.
  5. 5 . The UE of claim 1 , wherein the UE is configured for using a sensor of the UE for acquiring an orientation estimate for the UE; and for using the orientation estimate and the reference spatial relation in order to adjust its frame of reference to that of a global one, and to then use this adjusted frame of reference as its new zero point for performing a beam sweep and/or for interference mitigation.
  6. 6 . The UE of claim 1 , wherein the UE is configured for transmitting the UL-RS using a spatial TX filter and for determining the spatial TX filter based on the reference spatial relation; and/or wherein the UE is configured for transmitting a plurality of UL-RS comprising the uplink RS along a plurality of associated different directions and for excluding an UL-RS associated with a direction that is associated with the reference spatial relation from transmission.
  7. 7 . The UE of claim 1 , wherein the UE is configured for receiving instructions for using at least one resource set each resource set having at least one resource and for transmitting at least the UL-RS in accordance with the instructions.
  8. 8 . The UE of claim 1 , wherein the UE is configured for transmitting a signal indicating the UL-RS to a different device to thereby instruct the different device to transmit the UL-RS on behalf of the UE.
  9. 9 . The UE of claim 1 , adapted to store information indicating a spatial relation between a reference RS and the target UL-RS, wherein UE is configured with respect to a spatial relation information for the UL RS in a first state and for using the reference spatial relation to derive a spatial filter for the UL-RS in the first state, wherein the configuration signal comprises information indicating the reference RS.
  10. 10 . The UE of claim 1 , wherein the UE is configured for determining a spatial RX filter acquired from a SS/PBCH block of a cell of the wireless communication network that serves the UE and for using the spatial RX filter as the reference spatial relation.
  11. 11 . The UE of claim 1 , wherein the UE is adapted to use a first plurality of resource sets for transmitting a second plurality of UL-RS from the plurality of RS, each resource set having at least one resource for transmitting an UL-RS of the plurality of UL-RS, wherein the UE is configured for performing a power control of a transmission power for transmitting the UL-RSs individually for a first resource set of the plurality of resource sets and a second resource set of the plurality of resource sets.
  12. 12 . The UE of claim 11 , wherein the UE is adapted, for performing the power control, to determine a transmission power to be used for the first resource set or the second resource set based on at least one of information indicating a position of the UE and based on a position; information indicating a position of a dedicated receiver of the UL-RS; and information indicating a channel condition between the UE and the dedicated receiver.
  13. 13 . The UE of claim 11 , wherein the UE is configured for transmitting the UL-RS towards a dedicated TRP and for performing the power control for the first resource set or the second resource set comprising a resource used for transmitting the UL-RS to the dedicated reception point (RP) using a pathloss reference with respect to a reference RP.
  14. 14 . The UE of claim 11 , wherein the UE is configured for using a scaling parameter to scale the transmission power between the first resource set and the second resource set and/or an offset parameter to offset the transmission power between the first resource set and the second resource set.
  15. 15 . The UE of claim 1 , wherein the UE is configured for receiving instructions from the wireless network to update or deactivate a use of the reference spatial relation; wherein the UE is configured for operating according to the instructions.
  16. 16 . The UE of claim 15 , wherein the UE is configured for receiving the instructions as predictive instructions related to a future position or orientation and for implementing the instructions at the future position or orientation.
  17. 17 . The UE of claim 15 , wherein the UE is configured for receiving information indicating a directional relation of the UE and/or power control related to a future predicated window; wherein the UE is configured for determining a change of a UE position or orientation in the wireless communication network and to adapt a parameter, e.g., a spatial filter or a power setting, used for transmitting the UL-RS based on the received information.
  18. 18 . The UE of claim 1 , wherein the UE is configured for updating the reference spatial relation; wherein the UE is configured for transmitting UL-RSs on at least a first time instant and a later second time instance and for using, at the first time instance the UL-RS along a default direction based on a channel condition of the UE and for updating the reference spatial relation for the second time instance based on a changed channel condition.

Description

CROSS-REFERENCES TO RELATED APPLICATIONS This application is a continuation of copending International Application No. PCT/EP2021/071809, filed Aug. 4, 2021, which is incorporated herein by reference in its entirety, and additionally claims priority from European Application No. EP 20 189 866.5, filed Aug. 6, 2020, which is incorporated herein by reference in its entirety. BACKGROUND OF THE INVENTION The present invention relates to a user equipment, to a controller entity, to a wireless communication network and for methods for operating devices described herein. The present invention in particular relates to a sounding reference signal (SRS) sounding procedure for a positioning. For positioning within 5G, the sounding procedure can be performed in a way that UE transmits an UL (uplink) signal towards multiple gNBs or TRPs (Transmission reception points). The UL transmitted signal, for example SRS (Sounding Reference Signal) can be transmitted by the UE on multiple Tx beams. Two modes of operation are supported for UL sounding: the first is the NW (network) can provide the UE with information on the Tx spatial filter for SRS transmission used for a UL transmission or for a DL (downlink) signal reception. The second mode is to allow the UE to perform Tx sweeping: i.e. transmitting SRS signals on different beams in different directions. According to the positioning sounding procedure in TS38.214, “If the UE is not configured with the higher layer parameter spatialRelationInfo the UE may use a fixed spatial domain transmission filter for transmissions of the SRS configured by the higher layer parameter SRS-for-positioning across multiple SRS resources or it may use a different spatial domain transmission filter across multiple SRS resources.” This means that a UE can be configured without spatialRelationInfo on multiple SRS resources where the UE choses to use different spatial TX filters to perform beam sweeping or a fixed beam. The choice of the spatial filter is normally a UE implementation issue; this is shown for example in FIG. 1 for the TX beam sweeping case. From this figure, it can be seen that the sounding procedure consumes a lot of resources if not optimized (i.e. the Tx and Rx combinations from the UE and gNBs). In FIG. 13 the UE transmits a plurality of signals in different transmissions Ti whilst the transmissions repeat for different beam settings of reception (Rx) beams of a serving base station (s-gNB) and a neighboring gNB (n-gNB 1). That is, FIG. 13 shows an uplink beam sweeping of release 16 of the standardization. SRS-SpatialRelationInfoPos-r16 ::= SEQUENCE { servingCellId-r16   ServCellIndex  OPTIONAL, -- Need S referenceSignal-r16CHOICE {  ssb-IndexServing-r16     SSB-Index,  csi-RS-IndexServing-r16  NZP-CSI-RS-ResourceId,   srs-SpatialRelation-16    SEQUENCE {    resourceSelection-r16      CHOICE {     srs-ResourceID-r16       SRS-ResourceID     srs-PosResourceID-r16       SRS-PosResourceID-r16   }   uplinkBWP-r16    BWP-Id  },  ssbNcell-r16  SSB-InfoNcell-r16,  dl-PRS-r16 DL-PRS-Info-r16   }} Thus, there is a need for an efficient positioning procedure. It is, thus, an object of the present invention to provide for UEs, a controller entity, for wireless communication networks and for operating said devices that allow for an efficient positioning procedure. SUMMARY An embodiment may have a user equipment (UE) configured for operating in a wireless communication network that supports a plurality of reference signals (RS) such as sounding reference signals, the UE comprising: a wireless interface configured for transceiving signals, comprising receiving a configuration signal having a configuration information indicating a reference spatial relation; a controller for evaluating the configuration information and to determine the reference spatial relation; wherein the UE is configured for using the reference spatial relation as a reference for an uplink RS (UL-RS) in the wireless communication network. Another embodiment may have a user equipment (UE) configured for operating in a wireless communication network that supports a plurality of reference signals (RS) such as sounding reference signals, the UE comprising: a wireless interface configured for transceiving signals; wherein the UE is configured for transmitting UL-RSs on at least a first time instant and a later second time instance and for using, at the first time instance the UL-RS along a default direction based on a channel condition of the UE, e.g., based on a hampered transmission, and for updating the reference spatial relation for the second time instance based on a changed channel condition. Another embodiment may have a controller entity configured for controlling at least a part of an operation of a wireless communication network that supports a plurality of reference signals (RS) such as sounding reference signals, wherein the wireless communication network is adapted to communicate with a user equipment (UE), the cont