US 12,425,152 B2
Uplink non-codebook based precoder selection using DMRS measurement
Hemant Saggar, Irvine, CA (US); Iyab Issam Sakhnini, San Diego, CA (US); and Tao Luo, San Diego, CA (US)
Assigned to QUALCOMM Incorporated, San Diego, CA (US)
Filed by QUALCOMM Incorporated, San Diego, CA (US)
Filed on Oct. 29, 2021, as Appl. No. 17/452,972.
Claims priority of provisional application 63/108,233, filed on Oct. 30, 2020.
Prior Publication US 2022/0140970 A1, May 5, 2022
Int. Cl. H04L 5/00 (2006.01); H04B 7/06 (2006.01); H04L 25/02 (2006.01); H04W 72/20 (2023.01)
CPC H04L 5/0048 (2013.01) [H04L 25/0224 (2013.01); H04W 72/20 (2023.01); H04B 7/0626 (2013.01)] 20 Claims
OG exemplary drawing
 
1. An apparatus for wireless communication at a user equipment (UE), comprising:
memory; and
at least one processor coupled to the memory and configured to:
receive, from a base station (BS), downlink control information (DCI), a media access control (MAC) control element (CE) (MAC-CE), or radio resource control (RRC) signaling that indicates a length of a time window;
receive, from the BS, an uplink grant configured to schedule at least one uplink reference signal;
receive, from the BS, at least one downlink reference signal comprising at least one demodulation reference signal (DMRS) and at least one channel state information reference signal (CSI-RS) via at least one downlink channel, the at least one downlink channel comprising at least one of a physical downlink shared channel (PDSCH) or a physical downlink control channel (PDCCH);
measure, based on the at least one downlink reference signal and based on the at least one downlink channel being within the length of the time window from the uplink grant, the at least one downlink channel, the measuring being based jointly at least in part on the at least one DMRS and the at least one CSI-RS;
select at least one first uplink precoder for at least one uplink channel corresponding to the at least one downlink channel based on the measuring of the at least one downlink channel, the at least one first uplink precoder being non-codebook based;
transmit, to the BS, the at least one uplink reference signal based on the at least one first uplink precoder for the at least one uplink channel;
receive, from the BS, an indication of a schedule for a set of additional downlink reference signals after transmission of the at least one uplink reference signal, wherein a quantity of the at least one uplink reference signal is less than a specified quantity; and
transmit, to the BS based on a measurement of the set of additional downlink reference signals, a set of additional uplink reference signals associated with a set of additional uplink precoders.