Enabling uplink coherence with discrete antenna elements via signaling

An apparatus for wireless communication at a network node, comprising:

• one or more memories;
• and
• one or more processors, coupled to the one or more memories, configured to cause the network node to:
• receive an assistance indication that requests antenna coherence assistance to configure two or more discrete antenna elements at a user equipment (UE) with a coherence that satisfies a coherence threshold, wherein the two or more discrete antenna elements include N discrete antenna elements, N being an integer;
• and
• perform an antenna coherence establishment procedure with the UE, wherein, to perform the antenna coherence establishment procedure, the one or more processors are configured to:
• receive multiple portions of an uplink signal in multiple time durations, each respective portion of the multiple portions being received in a respective time duration of the multiple time durations, the multiple time durations being fewer than N time durations;
• calculate a phase difference between a first portion of the multiple portions of the uplink signal and at least a second portion of the multiple portions;
• and
• transmit an indication of the phase difference.

A method of wireless communication performed by a user equipment (UE), comprising:

• transmitting an assistance indication that requests antenna coherence assistance to configure two or more discrete antenna elements with a coherence that satisfies a coherence threshold, wherein the two or more discrete antenna elements include N discrete antenna elements, N being an integer;
• and
• performing, based at least in part on signaling, an antenna coherence establishment procedure that is based at least in part on:
• using a first discrete antenna element of the two or more discrete antenna elements as an anchor antenna element, and
• obtaining a respective phase relationship between the anchor antenna element and at least a second discrete antenna element of the two or more discrete antenna elements,
• wherein performing the antenna coherence establishment procedure comprises:
• receiving, when the signaling comprises a downlink signal and for each respective discrete antenna element of the N discrete antenna elements that is not the anchor antenna element, a respective symbol of the downlink signal using a respective antenna pair that includes the anchor antenna element and the respective discrete antenna element, or
• transmitting, when the signaling comprises an uplink signal for each respective discrete antenna element of the N discrete antenna elements that is not the anchor antenna element, multiple portions of the of the uplink signal in multiple time durations, each respective portion of the multiple portions being transmitted in a respective time duration of the multiple time durations and using the respective antenna pair that includes the anchor antenna element and the respective discrete antenna element.