公开(公告)号：US20220231740A1

公开(公告)日：2022-07-21

申请号：US17555437

申请日：2021-12-18

Applicant: MEDIATEK Inc.

Inventor： Sandeep Bhat ,  Chin-Kuo Jao ,  Jiann-Ching Guey

IPC: H04B7/06 ,  H04J1/06

Abstract: A method of downlink channel state information (DL CSI) measurement and reporting is proposed in FR1 frequency division duplex (FDD) systems. CSI reference signal (CSI-RS) is directed towards dominant spatial domain (SD, beam) and frequency domain (FD, delay) components in the propagation environment. By partial channel reciprocity, angles and delays in the DL channel can be obtained by UL channel measurement. UE only needs to measure and feedback the DL CSI corresponding to the dominant angles and delays. BS obtains the precoder in the antenna-frequency domain using the CSI feedback in the beam-delay domain. BS uses the precoder for transmission over Physical downlink shared channel (PDSCH). In one embodiment, UE reconstructs the DL channel on a multitude of delays using the DL channel estimated on a few beamformed CSI-RS and delay tap indices signaled from the network.