Methods and apparatuses for reference signal configuration
Embodiments of the present disclosure relate to methods and apparatuses for Reference Signal (RS) transmission. In example embodiments, a method implemented in a network device is provided. According to the method, the network device determines at least one set of CSI-RS resources for transmitting Tracking Reference Signal (TRS) to a terminal device. The network device further determines a first offset between a first slot to transmit a first signal for enabling transmission of the TRS and a second slot to transmit the TRS in the at least one set of CSI-RS resources. The first offset is different from a second offset between a third slot to transmit a second signal for enabling transmission of CSI-RS and a fourth slot to transmit the CSI-RS. The network device transmits a configuration indicating the at least one set of CSI-RS resources and the first offset to the terminal device.
1. A method performed by a base station, the method comprising:
transmitting, to a terminal device, first resource configuration for transmission of a Channel State Information Reference Signal (CSI-RS) for tracking,
wherein the first resource configuration comprises:
a parameter trs-Info set as true; and
a first parameter indicating a first offset between a first slot containing a first signal that triggers the transmission of the CSI-RS for tracking and a second slot in which the CSI-RS for tracking is transmitted,
wherein
the first offset is independent from a second offset indicated by a second parameter comprised in a second resource configuration for transmission of a CSI-RS without the parameter trs-Info set as true, and
wherein the second offset is between a third slot containing a second signal that triggers the transmission of the CSI-RS and a fourth slot in which the CSI-RS is transmitted; and
transmitting the CSI-RS for tracking, to the terminal device in the second slot.
2. The method of claim 1 , wherein the CSI-RS for tracking and the CSI-RS are associated with different Quasi-Co-Location (QCL) parameters.
3. The method of claim 1 , further comprising:
determining the first resource configuration,
wherein determining the first resource configuration comprises:
determining a distribution of at least one set of resources for the CSI-RS for tracking in one or more slots; and
determining the first offset,
wherein determining the first offset comprises:
determining the first offset using the distribution.
4. The method of claim 3 , wherein the distribution indicates that the at least one set of the resources for the CSI-RS for tracking includes a first resource set with two periodic resources for the CSI-RS for tracking in one slot, and the determining the first offset comprises:
determining the first offset using the first resource set.
5. The method of claim 3 , wherein the distribution indicates that the at least one set of resources for the CSI-RS for tracking includes a second resource set with four periodic resources for the CSI-RS for tracking in two consecutive slots, and the determining the first offset comprises:
determining the first offset using at least one of the two consecutive slots.
6. The method of claim 3 , wherein the distribution indicates that the at least one set of resources for the CSI-RS for tracking includes two resource sets each with two periodic resources for the CSI-RS for tracking in one slot, and the determining the first offset comprises:
determining the first offset using at least one of the two resource sets.
7. The method of claim 1 , further comprising:
determining the first offset,
wherein determining the first offset comprises:
obtaining a first set of candidate offsets predefined for the CSI-RS for tracking; and
determining the first offset from the first set of candidate offsets, the first set of candidate offsets being at least in part different from a second set of candidate offsets, the second offset being determined from the second set of candidate offsets.
8. The method of claim 1 , wherein the CSI-RS for tracking is aperiodic.
9. The method of claim 1 , wherein the first signal is transmitted in a Downlink Control Information (DCI) format.
10. The method of claim 1 , wherein the CSI-RS for tracking is associated with a first subcarrier spacing (SCS) and the first signal is associated with a second SCS that is different from the first SCS, and
wherein the method further comprises:
determining the first offset,
wherein determining the first offset comprises:
determining the first offset at least using the first SCS.
11. The method of claim 1 , further comprising:
transmitting, at least using the first resource configuration, the first signal and the CSI-RS for tracking to the terminal device.
12. A method performed by a terminal device, the method comprising:
receiving, from a base station, first resource configuration for transmission of a Channel State Information Reference Signal (CSI-RS) for tracking,
wherein the first resource configuration comprises:
a parameter trs-Info set as true; and
a first parameter indicating a first offset between a first slot containing a first signal that triggers the transmission of the CSI-RS for tracking and a second slot in which the CSI-RS for tracking is received,
wherein
the first offset is independent from a second offset indicated by a second parameter comprised in a second resource configuration for transmission of a CSI-RS without the parameter trs-Info set as true,
wherein the second offset is between a third slot containing a second signal that triggers the transmission of the CSI-RS and a fourth slot in which the CSI-RS is received; and
receiving the CSI-RS for tracking from the base station in the second slot.
13. The method of claim 12 , wherein the CSI-RS for tracking and the CSI-RS are associated with different Quasi-Co-Location (QCL) parameters.
14. The method of claim 12 , wherein the CSI-RS for tracking is aperiodic.
15. The method of claim 12 , wherein the first signal is received in a Downlink Control Information (DCI) format.
16. The method of claim 12 , wherein the CSI-RS for tracking is associated with a first subcarrier spacing (SCS) and the first signal is associated with a second SCS that is different from the first SCS, and
wherein the first offset is determined at least using the first SCS.
17. The method of claim 12 , further comprising:
receiving, at least using the first resource configuration, the first signal and the CSI-RS for tracking from the base station.
18. A base station comprising:
a transmitter configured to:
transmit, to a terminal device, first resource configuration for transmission of a Channel State Information Reference Signal (CSI-RS) for tracking,
wherein the first resource configuration comprises:
a parameter trs-Info set as true; and
a first parameter indicating a first offset between a first slot containing a first signal that triggers the transmission of the CSI-RS for tracking and a second slot in which the CSI-RS for tracking is transmitted,
wherein
the first offset is independent from a second offset indicated by a second parameter comprised in a second resource configuration for transmission of a CSI-RS without the parameter trs-Info set as true, and
wherein the second offset is between a third slot containing a second signal that triggers the transmission of the CSI-RS and a fourth slot in which the CSI-RS is transmitted; and
transmit the CSI-RS for tracking to the terminal device in the second slot.