Uplink transmission techniques for exposure limited transmissions
Methods, systems, and devices for wireless communications are described for handling uplink grants that have associated uplink transmission that may exceed exposure limits. Exposure limits may be based on maximum permissible exposure (MPE) limits of millimeter wave transmissions and may be determined at a user equipment (UE) and provided to a base station. If the UE receives an uplink grant for a transmission in which an associated uplink transmission would exceed the exposure limits, the UE may drop the uplink transmission prior to forming a transport block, transmit control signaling to the base station to indicate the exposure limits at the UE, or combinations thereof.
1. A method for wireless communication at a user equipment (UE), comprising:
receiving, from a base station, a first uplink grant indicating a set of uplink transmission resources for an uplink transmission in a high band frequency range;
determining, based at least in part on the set of uplink transmission resources and one or more associated uplink transmission parameters, that the uplink transmission using the set of uplink transmission resources exceeds a maximum transmission power available to the UE that is based on an exposure threshold;
determining that the uplink transmission includes control information multiplexed with data; and
transmitting, based at least in part on the determining that the uplink transmission includes the control information, the uplink transmission with an increased uplink transmission power for a first subset of the set of uplink transmission resources associated with the control information relative to a reduced uplink transmission power for a second subset of the set of uplink transmission resources associated with the data.
2. The method of claim 1 , wherein the transmitting at the increased uplink transmission power in the first subset of the set of uplink transmission resources and at the reduced uplink transmission power in the second subset of the set of uplink transmission resources provides an aggregate transmission power that is within the exposure threshold.
3. The method of claim 1 , further comprising:
refraining from forming a transport block with the data.
4. The method of claim 1 , wherein the transmitting further comprises:
transmitting padding rather than the data in the second subset of the set of uplink transmission resources.
5. The method of claim 1 , further comprising:
receiving, from the base station, a second uplink grant indicating a second set of uplink transmission resources for a second uplink transmission in the high band frequency range.
6. The method of claim 5 , further comprising:
determining that the second uplink transmission at a second uplink transmission power using the second set of uplink transmission resources is within the exposure threshold;
determining whether a transport block with the data is a self decodable transport block;
forming the data into the transport block based on determining that the transport block with the data is self decodable and transmitting the transport block in the second uplink transmission; and
dropping the second uplink transmission based on determining that the transport block with the data is not self decodable.
7. The method of claim 5 , further comprising:
determining that the second uplink transmission using the second set of uplink transmission resources exceeds a second maximum transmission power available to the UE that is based on the exposure threshold;
determining that the second uplink transmission includes second control information multiplexed with data; and
transmitting the second uplink transmission at an increased second uplink transmission power for a first subset of the second set of uplink transmission resources associated with the second control information relative to a second uplink transmission power for a second subset of the second set of uplink transmission resources associated with the data.
8. An apparatus for wireless communication at a user equipment (UE), comprising:
a processor;
memory coupled with the processor; and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive, from a base station, a first uplink grant indicating a set of uplink transmission resources for an uplink transmission in a high band frequency range;
determine, based at least in part on the set of uplink transmission resources and one or more associated uplink transmission parameters, that the uplink transmission using the set of uplink transmission resources exceeds a maximum transmission power available to the UE that is based on an exposure threshold;
determine that the uplink transmission includes control information multiplexed with data; and
transmit, based at least in part on the determining that the uplink transmission includes the control information, the uplink transmission with an increased uplink transmission power for a first subset of the set of uplink transmission resources associated with the control information relative to a reduced uplink transmission power for a second subset of the set of uplink transmission resources associated with the data.
9. The apparatus of claim 8 , wherein the transmitting at the increased uplink transmission power in the first subset of the set of uplink transmission resources and at the reduced uplink transmission power in the second subset of the set of uplink transmission resources provides an aggregate transmission power that is within the exposure threshold.
10. The apparatus of claim 8 , wherein the instructions are further executable by the processor to cause the apparatus to:
refrain from forming a transport block with the data.
11. The apparatus of claim 8 , wherein the instructions to transmit the uplink transmission are further executable by the processor to cause the apparatus to:
transmit padding rather than the data in the second subset of the set of uplink transmission resources.
12. The apparatus of claim 8 , wherein the instructions are further executable by the processor to cause the apparatus to:
receive, from the base station, a second uplink grant indicating a second set of uplink transmission resources for a second uplink transmission in the high band frequency range.
13. The apparatus of claim 12 , wherein the instructions are further executable by the processor to cause the apparatus to:
determine that the second uplink transmission at a second uplink transmission power using the second set of uplink transmission resources is within the exposure threshold;
determine whether a transport block with the data is a self decodable transport block;
form the data into the transport block based on determining that the transport block with the data is self decodable and transmitting the transport block in the second uplink transmission; and
drop the second uplink transmission based on determining that the transport block with the data is not self decodable.
14. The apparatus of claim 12 , wherein the instructions are further executable by the processor to cause the apparatus to:
determine that the second uplink transmission using the second set of uplink transmission resources exceeds a second maximum transmission power available to the UE that is based on the exposure threshold;
determine that the second uplink transmission includes second control information multiplexed with data; and
transmit the second uplink transmission at an increased second uplink transmission power for a first subset of the second set of uplink transmission resources associated with the second control information relative to a second uplink transmission power for a second subset of the second set of uplink transmission resources associated with the data.
15. An apparatus for wireless communication at a user equipment (UE), comprising:
means for receiving, from a base station, a first uplink grant indicating a set of uplink transmission resources for an uplink transmission in a high band frequency range;
means for determining, based at least in part on the set of uplink transmission resources and one or more associated uplink transmission parameters, that the uplink transmission using the set of uplink transmission resources exceeds a maximum transmission power available to the UE that is based on an exposure threshold;
means for determining that the uplink transmission includes control information multiplexed with data; and
means for transmitting, based at least in part on the determining that the uplink transmission includes the control information, the uplink transmission with an increased uplink transmission power for a first subset of the set of uplink transmission resources associated with the control information relative to a reduced uplink transmission power for a second subset of the set of uplink transmission resources associated with the data.
16. The apparatus of claim 15 , wherein the transmitting at the increased uplink transmission power in the first subset of the set of uplink transmission resources and at the reduced uplink transmission power in the second subset of the set of uplink transmission resources provides an aggregate transmission power that is within the exposure threshold.
17. The apparatus of claim 15 , further comprising:
means for refraining from forming a transport block with the data.
18. The apparatus of claim 15 , wherein the means for the transmitting the uplink transmission further comprise:
means for transmitting padding rather than the data in the second subset of the set of uplink transmission resources.
19. The apparatus of claim 15 , further comprising:
means for receiving, from the base station, a second uplink grant indicating a second set of uplink transmission resources for a second uplink transmission in the high band frequency range.
20. The apparatus of claim 19 , further comprising:
means for determining that the second uplink transmission at a second uplink transmission power using the second set of uplink transmission resources is within the exposure threshold;
means for determining whether a transport block with the data is a self decodable transport block;
means for forming the data into the transport block based on determining that the transport block with the data is self decodable and transmitting the transport block in the second uplink transmission; and
means for dropping the second uplink transmission based on determining that the transport block with the data is not self decodable.