RAN1 confirms 1/8 density for two 24-port CSI-RS resources

Radio Access Network working group 1 (RAN1) recorded the confirmation under agenda item 9.2. Submissions framed this as New Radio (NR) multiple-input multiple-output (MIMO) Phase 6 work. Each non-zero-power (NZP) channel state information reference signal (CSI-RS) resource has 24 ports. The chair notes specify "K=2 24-port NZP CSI-RS resources in a resource set aggregating 48 CSI-RS ports". K=2 identifies the number of resources in that set. The confirmation covers frequency-domain density 1/8 for the working assumption made at meeting 123.

Source: R1-2606757, Ad-Hoc Chair (Ericsson), 3GPP TSG RAN WG1 #126, chair notes, agenda item 9.2.

Xiaomi proposed confirming the K=2 working assumption and also proposed 1/8 density for K=3 16-port resources. The K=3 proposal also aggregates 48 ports, but the chair notes excerpt does not mention it. CATT proposed confirming 1/8 density for a set of K-resource configurations aggregating 48, 64 or 128 ports. That proposal concerns wideband channel state information reporting based on Release 19 Type-1 codebooks.

ETRI wrote "Do not support to confirm the working assumption" for the K=2 case. Nokia's first preference was to reject additional configurations at densities 1/3, 1/4, 1/6 and 1/8, including the K=2 assumption. Its second preference was to support all remaining configurations. The register marked all four papers not treated at meeting 126, with no decisions recorded for those papers. The chair notes nevertheless confirmed the K=2 24-port working assumption.

Source: R1-2606277, ETRI, 3GPP TSG RAN WG1 #126. © ETRI.