RAN1 #125 agreed to define both 6GR control-channel mapping types

RAN1 (radio layer 1 working group) #125 agreed to define both mapping types for 6GR (sixth-generation radio) PDCCH (physical downlink control channel). For each CORESET (control resource set), the report records a working assumption: "there is only one CCE-to-REG mapping scheme: either interleaved or non-interleaved." CCE means control channel element, and REG means resource element group. The RAN1 #125 report was approved at RAN1 #126 under agenda item 10.5.2.1.

Source: R1-2605181, ETSI MCC, 3GPP TSG RAN WG1 #126, report, agenda item 10.5.2.1.

The report says RAN1 is to confirm the working assumption that a REG bundle is the minimal PDCCH precoding granularity. It states the bundle is at least the interleaving unit for interleaved CCE-to-REG mapping. The number of REGs per bundle remains for further study. NTT DOCOMO wrote "Consider REG bundle at least as the unit of CCE-to-REG mapping." Its RAN1 #125 contribution refers to confirming a working assumption at RAN1#124bis.

Source: R1-2604739, NTT DOCOMO, 3GPP TSG RAN WG1 #125. © NTT DOCOMO.

OPPO proposed confirming that a REG bundle contains REGs and serves as the interleaving unit for interleaved mapping. Samsung suggested precoder granularity of 2, 3 or 6 REGs and left larger granularity for further study. Neither the OPPO nor Samsung contribution was treated at RAN1 #125.