Guard period optimization for multi-antenna user equipments
Certain aspects of the present disclosure provide techniques for selecting an antenna configuration for transmitting in a wireless communication network. An example technique may include determining that a front guard period is not scheduled between a scheduled uplink transmission and a scheduled sounding reference signal (SRS) transmission, and based on the determination, transmitting the scheduled SRS transmission using a first antenna configuration after transmitting the scheduled uplink transmission using the first antenna configuration.
1. A method of selecting antenna configurations for communicating in a wireless communication network by a user equipment, the method comprising:
transmitting, to a base station, a scheduled sounding reference signal (SRS) transmission using a first antenna configuration; and
receiving, from the base station, a scheduled downlink transmission using a second antenna configuration that is different than the first antenna configuration without using a rear guard period between the transmitting of the scheduled SRS transmission and the receiving of the scheduled downlink transmission based on a determination that the rear guard period is not needed between the scheduled SRS transmission and the scheduled downlink transmission, wherein the determination that the rear guard period is not needed is based on a determination that twice a propagation delay between the base station and the user equipment is sufficient to allow for changing between the first antenna configuration and the second antenna configuration without the rear guard period.
2. The method of claim 1 , further comprising receiving downlink control information (DCI) from the base station indicating that the rear guard period is not needed, wherein the determination that the rear guard period is not needed is based on receiving the DCI.
3. The method of claim 1 , wherein the determination that the rear guard period is not needed is based on a determination that the rear guard period is not necessary to receive a first symbol of the scheduled downlink transmission.
4. The method of claim 1 , further comprising receiving a network resource allocation from a network, wherein:
the network resource allocation comprises an SRS resource set,
a first SRS resource of the SRS resource set is separated in time from a second SRS resource of the SRS resource set by a middle guard period, and
the first SRS resource of the SRS resource set is preceded in time by a front guard period.
5. The method of claim 4 , wherein the front guard period comprises a zero-power SRS resource.
6. The method of claim 1 , wherein the wireless communication network is a 5G new radio network.
7. The method of claim 1 , wherein the scheduled SRS transmission is transmitted in at least a last symbol in time of a first slot, wherein the scheduled downlink transmission is received in at least a first symbol in time of a second slot, and wherein the second slot is after and adjacent in time to the first slot.
8. A user equipment comprising:
a memory; and
one or more processors coupled to the memory, wherein the one or more processors are, individually or collectively, configured to cause the user equipment to:
transmit, to a base station, a scheduled sounding reference signal (SRS) transmission using a first antenna configuration; and
receive, from the base station, a scheduled downlink transmission using a second antenna configuration that is different than the first antenna configuration without using a rear guard period between the transmitting of the scheduled SRS transmission and the receiving of the scheduled downlink transmission based on a determination that the rear guard period is not needed between the scheduled SRS transmission and the scheduled downlink transmission, wherein the determination that the rear guard period is not needed is based on a determination that twice a propagation delay between the base station and the user equipment is sufficient to allow for changing between the first antenna configuration and the second antenna configuration without the rear guard period.
9. The user equipment of claim 8 , wherein the one or more processors are further configured to, individually or collectively, cause the user equipment to receive downlink control information (DCI) from the base station indicating that the rear guard period is not needed, wherein the determination that the rear guard period is not needed is based on receiving the DCI.
10. The user equipment of claim 8 , wherein the determination that the rear guard period is not needed is based on a determination that the rear guard period is not necessary to receive a first symbol of the scheduled downlink transmission.
11. The user equipment of claim 8 , wherein the one or more processors are further configured to, individually or collectively, cause the user equipment to receive a network resource allocation from a network, wherein:
the network resource allocation comprises an SRS resource set,
a first SRS resource of the SRS resource set is separated in time from a second SRS resource of the SRS resource set by a middle guard period, and
the first SRS resource of the SRS resource set is preceded in time by a front guard period.
12. The user equipment of claim 11 , wherein the front guard period comprises a zero-power SRS resource.
13. The user equipment of claim 8 , wherein the scheduled SRS transmission is transmitted in at least a last symbol in time of a first slot, wherein the scheduled downlink transmission is received in at least a first symbol in time of a second slot, and wherein the second slot is after and adjacent in time to the first slot.
14. A user equipment comprising:
means for transmitting, to a base station, a scheduled sounding reference signal (SRS) transmission using a first antenna configuration; and
means for receiving, from the base station, a scheduled downlink transmission using a second antenna configuration that is different than the first antenna configuration without using a rear guard period between the transmitting of the scheduled SRS transmission and the receiving of the scheduled downlink transmission based on a determination that the rear guard period is not needed between the scheduled SRS transmission and the scheduled downlink transmission, wherein the determination that the rear guard period is not needed is based on a determination that twice a propagation delay between the base station and the user equipment is sufficient to allow for changing between the first antenna configuration and the second antenna configuration without the rear guard period.
15. The user equipment of claim 14 , further comprising means for receiving downlink control information (DCI) from the base station indicating that the rear guard period is not needed, wherein the determination that the rear guard period is not needed is based on receiving the DCI.
16. The user equipment of claim 14 , wherein the determination that the rear guard period is not needed is based on a determination that the rear guard period is not necessary to receive a first symbol of the scheduled downlink transmission.
17. The user equipment of claim 14 , further comprising means for receiving a network resource allocation from a network, wherein:
the network resource allocation comprises an SRS resource set,
a first SRS resource of the SRS resource set is separated in time from a second SRS resource of the SRS resource set by a middle guard period, and
the first SRS resource of the SRS resource set is preceded in time by a front guard period.
18. The user equipment of claim 17 , wherein the front guard period comprises a zero-power SRS resource.
19. The user equipment of claim 14 , wherein the scheduled SRS transmission is transmitted in at least a last symbol in time of a first slot, wherein the scheduled downlink transmission is received in at least a first symbol in time of a second slot, and wherein the second slot is after and adjacent in time to the first slot.
20. A non-transitory computer readable medium comprising instructions, that when executed by a user equipment, cause the user equipment to perform a method of selecting antenna configurations for communicating in a wireless communication network, the method comprising:
transmitting, to the base station, a scheduled sounding reference signal (SRS) transmission using a first antenna configuration; and
receiving, from the base station, a scheduled downlink transmission using a second antenna configuration that is different than the first antenna configuration without using a rear guard period between the transmitting of the scheduled SRS transmission and the receiving of the scheduled downlink transmission based on a determination that the rear guard period is not needed between the scheduled SRS transmission and the scheduled downlink transmission, wherein the determination that the rear guard period is not needed is based on a determination that twice a propagation delay between the base station and the user equipment is sufficient to allow for changing between the first antenna configuration and the second antenna configuration without the rear guard period.
21. The non-transitory computer readable medium of claim 20 , the method further comprising receiving downlink control information (DCI) from the base station indicating that the rear guard period is not needed, wherein the determination that the rear guard period is not needed is based on receiving the DCI.
22. The non-transitory computer readable medium of claim 20 , wherein the determination that the rear guard period is not needed is based on a determination that the rear guard period is not necessary to receive a first symbol of the scheduled downlink transmission.
23. The non-transitory computer readable medium of claim 20 , the method further comprising receiving a network resource allocation from a network, wherein:
the network resource allocation comprises an SRS resource set,
a first SRS resource of the SRS resource set is separated in time from a second SRS resource of the SRS resource set by a middle guard period, and
the first SRS resource of the SRS resource set is preceded in time by a front guard period.
24. The non-transitory computer readable medium of claim 23 , wherein the front guard period comprises a zero-power SRS resource.
25. The non-transitory computer readable medium of claim 20 , wherein the wireless communication network is a 5G new radio network.
26. The non-transitory computer readable medium of claim 20 , wherein the scheduled SRS transmission is transmitted in at least a last symbol in time of a first slot, wherein the scheduled downlink transmission is received in at least a first symbol in time of a second slot, and wherein the second slot is after and adjacent in time to the first slot.