Handling of radio frequency front-end group delays for round trip time estimation
摘要
說明書
During the downlink subframe 604, the UE 102 measures the RTTM arrival times (e.g., t2) of each downlink RTTM transmitted by the gNodeBs 202-206 during the downlink subframes 606 and 608. The UE 102 can also calculate the actual arrival times (e.g., t2′) of each downlink RTTM. The UE 102 derives its downlink subframe timing from the downlink signal received from the serving gNodeB on the PDCCH. That is, the UE 102 sets the start time of its PDCCH subframe to the time at which it received the downlink signal from the serving gNodeB.
The UE 102 is instructed to report its RTT measurements (e.g., the UE actual turn-around time (t3′?t2′) and/or the UE measured turn-around time (t3′?t2′)) on the Physical Uplink Shared Channel (PUSCH) during a subsequent uplink subframe, which it does during uplink subframe 612. Like the RTTM signals transmitted by the gNodeBs 202-206, the RTTR waveform transmitted by the UE 102 may be a wideband signal to enable the gNodeBs to make precise timing measurements of its arrival.
