Measurement period for beam reporting
In NR, a gNB utilizes multiple antennas and beam forming techniques for downlink transmissions to UEs. Described herein are methods and apparatus by which a UE measures the quality of multiple directional beams received from a gNB.
1. An apparatus for a user equipment (UE), the apparatus comprising:
memory and processing circuitry, wherein, the processing circuitry is to:
measure reference signal received power (RSRP) of one or more channel state information reference signals (CSI-RSs), where the CSI-RSs are transmitted from a base station (BS) via different directional beams;
for each of one or more beams, time average a plurality of RSRPs for the CSI-RS associated with that beam received at different time slots; and
periodically encode a beam report for sending to the BS in accordance with a reporting period, wherein the beam report includes, for each of the one or more beams, the corresponding time averaged RSRP of the corresponding CSI-RS, wherein a sliding window is applied for averaging when the reporting period is less than a beam measurement period needed for averaging.
2. The apparatus of claim 1 wherein the processing circuitry is to encode the beam report for sending to the BS in response to downlink control information (DCI) received from the BS over a physical downlink control channel (PDCCH).
3. The apparatus of claim 1 wherein the processing circuitry is to average a number N RSRPs for the beam report, where the number N is received from the BS.
4. The apparatus of claim 1 wherein the processing circuitry is to average a plurality of RSRPs for the beam report from a CSI-RS received in different slots.
5. The apparatus of claim 1 , further comprising:
antennas; and
a transceiver coupled to the antennas and to the processing circuitry.
6. The apparatus of claim 1 , wherein the base station is a gNodeB of 3GPP 5G New Radio.
7. A non-transitory computer-readable storage medium comprising instructions to cause processing circuitry of a user equipment (UE), upon execution of the instructions by the processing circuitry, to:
measure reference signal received power (RSRP) of one or more channel state information reference signals (CSI-RSs), where the CSI-RSs are transmitted from a base station (BS) via different directional beams;
for each of one or more beams, time average a plurality of RSRPs for the CSI-RS associated with that beam received at different time slots; and,
periodically encode a beam report for sending to the BS in accordance with a reporting period, wherein the beam report includes, for each of the one or more beams, the time averaged RSRP of the corresponding CSI-RS, wherein a sliding window is applied for averaging when the reporting period is less than a beam measurement period needed for averaging.
8. The non-transitory computer-readable storage medium of claim 7 further comprising instructions to encode the beam report for sending to the BS in response to downlink control information (DCI) received from the BS over a physical downlink control channel (PDCCH).
9. The non-transitory computer-readable storage medium of claim 7 further comprising instructions to average a number N RSRPs for the beam report, where the number N is received from the BS.
10. The non-transitory computer-readable storage medium of claim 7 further comprising instructions to average a plurality of RSRPs for the beam report from a CSI-RS received in different slots.
11. An apparatus for a base station (BS), the apparatus comprising:
memory and processing circuitry, wherein, the processing circuitry is to encode instructions for sending to a user equipment (UE) that instruct the UE to:
measure reference signal received power (RSRP) of one or more channel state information reference signals (CSI-RSs), where the CSI-RSs are transmitted from the BS via different directional beams;
for each of one or more beams, time average a plurality of RSRPs for the CSI-RS associated with that beam received at different time slots; and,
periodically encode a beam report for sending to the BS in accordance with a reporting period, wherein the beam report includes, for each of the one or more beams, the corresponding time averaged RSRP of the corresponding CSI-RS, wherein a sliding window is applied for averaging when the reporting period is less than a beam measurement period needed for averaging.
12. The apparatus of claim 11 wherein the processing circuitry is to encode instructions that instruct the UE to encode the beam report for sending to the BS in response to downlink control information (DCI) received from the BS over a physical downlink control channel (PDCCH).
13. The apparatus of claim 11 wherein the processing circuitry is to encode instructions that instruct the UE to average a number N RSRPs for the beam report, where the number N is received from the BS.
14. The apparatus of claim 11 wherein the processing circuitry is to encode instructions that instruct the UE to average a plurality of RSRPs for the beam report from a CSI-RS received in different slots.