CN-121986458-A - Fine frequency domain channel state information for large bandwidth

Abstract

Certain aspects of the present disclosure provide techniques for fine Frequency Domain (FD) Channel State Information (CSI) for large bandwidths. An example method performed at a User Equipment (UE) generally includes receiving signaling from a network entity to configure the UE for CSI reporting based on a plurality of Spatial Domain (SD) bases and a subband size, selecting the plurality of SD bases from a set of candidate SD bases based on CSI reference signal (CSI-RS) measurements, calculating FD phase rotation parameters specific to each of the plurality of SD bases based on FD phase rotation units less than the subband size for at least some of the plurality of SD bases, and sending CSI to the network entity that includes an indication of the plurality of SD bases and the FD phase rotation parameters.

Inventors

• DAI JING
• WU LIANGMING
• L .xiao
• ZHANG YU
• HUANG DIE

Assignees

• 高通股份有限公司

Dates

Publication Date

20260505

Application Date

20231016

Claims (20)

1. 1. An apparatus for wireless communication at a User Equipment (UE), the apparatus comprising: At least one memory including computer-executable instructions, and One or more processors configured to execute the computer-executable instructions and cause the UE to: Receiving signaling from a network entity to configure the UE for Channel State Information (CSI) reporting based on a plurality of Spatial Domain (SD) bases and subband sizes; selecting the plurality of SD-bases from a set of candidate SD-bases based on CSI reference signal (CSI-RS) measurements; Calculating, for at least some of the plurality of SD bases, frequency Domain (FD) phase rotation parameters specific to each of the plurality of SD bases based on FD phase rotation units that are less than the subband size, and And transmitting CSI comprising an indication of the plurality of SD bases and the FD phase rotation parameters to the network entity.
2. 2. The apparatus of claim 1, wherein the one or more processors are further configured to cause the UE to determine a size of the FD phase rotation unit based on CSI-RS frequency density.
3. 3. The device of claim 1, wherein the FD phase rotation parameters are quantized to integer values based on a total number of the FD phase rotation units in a wideband.
4. 4. The device of claim 1, wherein the FD phase rotation parameters are quantized to fractional values based on a total number of the FD phase rotation units and an oversampling parameter in a wideband.
5. 5. The device of claim 1, wherein values of at least some of the FD phase rotation parameters are relative to a reference SD basis of the plurality of SD bases.
6. 6. The apparatus of claim 1, wherein each of the FD phase rotation parameters is common to both polarizations.
7. 7. The apparatus of claim 1, wherein each of the FD phase rotation parameters is common to all transmit layers associated with the CSI.
8. 8. The device of claim 1, wherein the FD phase rotation parameters comprise FD phase rotation parameters specific to a sending layer associated with the CSI.
9. 9. The apparatus of claim 1, wherein: The CSI is based on a port selection codebook, and The FD phase rotation parameters include FD phase rotation parameters specific to each selected port of a plurality of selected ports.
10. 10. The apparatus of claim 1, wherein the CSI lacks an indication of FD base selection in addition to the Frequency Domain (FD) phase rotation parameter.
11. 11. The device of claim 1, wherein the CSI comprises at least one of a layer common or layer specific FD base selection in addition to the Frequency Domain (FD) phase rotation parameters.
12. 12. The apparatus of claim 1, wherein: The CSI includes a Channel Quality Indicator (CQI), and The CQI is calculated based on a PDSCH assumed by a UE having a frequency granularity of at least one of a physical resource block group (PRG) level, a size of the FD phase rotation unit, a Resource Block (RB) level, or a subcarrier level.
13. 13. The apparatus of claim 12, wherein delay-related quasi co-location (QCL) is not assumed between the UE-assumed PDSCH and the CSI-RS based on the frequency granularity being less than a size of the PRG.
14. 14. The apparatus of claim 1, wherein: the CSI is transmitted in at least a first portion and a second portion, and The FD phase rotation parameter is transmitted in either a packed group zero or a packed group one of the second portion.
15. 15. An apparatus for wireless communication at a network entity, the apparatus comprising: At least one memory including computer-executable instructions, and One or more processors configured to execute the computer-executable instructions and cause the network entity to: Transmitting signaling to a User Equipment (UE) to configure the UE for Channel State Information (CSI) reporting based on a plurality of Spatial Domain (SD) bases and subband sizes; Transmitting CSI reference signals (CSI-RS) on resources associated with the set of candidate SD bases; Receiving CSI from the UE, the CSI comprising an indication of the plurality of SD bases and Frequency Domain (FD) phase rotation parameters for at least some of the plurality of SD bases that are based on FD phase rotation units that are less than the subband size, specific to each of the plurality of SD bases, and PDSCH is transmitted to the UE using precoding based on the received CSI.
16. 16. The apparatus of claim 15, wherein the one or more processors are further configured to cause the network entity to determine the size of the FD phase rotation unit based on CSI-RS frequency density.
17. 17. The device of claim 15, wherein the FD phase rotation parameters are quantized to integer values based on a total number of the FD phase rotation units in a wideband.
18. 18. The device of claim 15, wherein the FD phase rotation parameters are quantized to fractional values based on a total number of the FD phase rotation units and an oversampling parameter in a wideband.
19. 19. The device of claim 15, wherein values of at least some of the FD phase rotation parameters are relative to a reference SD basis of the plurality of SD bases.
20. 20. The apparatus of claim 15, wherein each of the FD phase rotation parameters is common to both polarizations.

Description

Fine frequency domain channel state information for large bandwidth Technical Field Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for reporting fine Frequency Domain (FD) Channel State Information (CSI) for a large bandwidth. Background Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcast, or other similar types of services. These wireless communication systems may employ multiple-access techniques that are capable of supporting communication with multiple users by sharing the available wireless communication system resources with those users. Despite the tremendous technological advances made over the years in wireless communication systems, challenges remain. For example, complex and dynamic environments may still attenuate or block signals between a wireless transmitter and a wireless receiver. Accordingly, there is a continuing desire to improve the technical performance of wireless communication systems, including, for example, improving the speed and data carrying capacity of communications, improving the efficiency of use of shared communication media, reducing the power used by transmitters and receivers in performing communications, improving the reliability of wireless communications, avoiding redundant transmissions and/or receptions and associated processing, improving the coverage area of wireless communications, increasing the number and types of devices accessible to the wireless communication system, increasing the ability of different types of devices to communicate with each other, increasing the number and types of wireless communication media available for use, and the like. Accordingly, there is a need for further improvements in wireless communication systems to overcome the foregoing technical challenges and others. Disclosure of Invention One aspect provides a method for wireless communication at a User Equipment (UE). The method includes receiving signaling from a network entity to configure the UE for Channel State Information (CSI) reporting based on a plurality of Spatial Domain (SD) bases and a subband size, selecting the plurality of SD bases from a set of candidate SD bases based on CSI reference signal (CSI-RS) measurements, calculating, for at least some of the plurality of SD bases, a Frequency Domain (FD) phase rotation parameter specific to each of the plurality of SD bases based on a FD phase rotation unit that is less than the subband size, and transmitting CSI to the network entity that includes an indication of the plurality of SD bases and the FD phase rotation parameter. Another aspect provides a method for wireless communication at a network entity. The method includes transmitting signaling to a User Equipment (UE) to configure the UE for Channel State Information (CSI) reporting based on a plurality of Spatial Domain (SD) bases and a subband size, transmitting CSI reference signals (CSI-RSs) on resources associated with a set of candidate SD bases, receiving CSI from the UE, the CSI including an indication of the plurality of SD bases and a Frequency Domain (FD) phase rotation parameter for at least some of the plurality of SD bases that is based on less than the subband size, specific to each of the plurality of SD bases, and transmitting PDSCH to the UE using precoding based on the received CSI. Other aspects provide an apparatus operable, configured, or otherwise adapted to perform any one or more of the foregoing methods and/or those described elsewhere herein, a non-transitory computer-readable medium comprising instructions that, when executed by one or more processors of the apparatus, cause the apparatus to perform the foregoing methods and those described elsewhere herein, a computer program product embodied on a computer-readable storage medium comprising code for performing the foregoing methods and those described elsewhere herein, and/or an apparatus comprising means for performing the foregoing methods and those described elsewhere herein. By way of example, an apparatus may comprise a processing system, a device with a processing system, or a processing system cooperating over one or more networks. For purposes of illustration, the following description and the annexed drawings set forth certain features. Drawings The drawings depict certain features of the various aspects described herein and are not intended to limit the scope of the disclosure. Fig. 1 depicts an example wireless communication network. Fig. 2 depicts an example exploded base station architecture. Fig. 3 depicts aspects of an example base station and an example user equipment. Fig. 4A, 4B, 4C, and 4D depict various example aspects of data structures for a wireless communication network. Fig. 5 depicts an example frequency range and mid-band. Fig. 6A depicts an example pre-decoder matrix. Fig. 6B depicts example content of enha