Indicating energy and thermal constraints in a wireless communications system

1. A method for wireless communications, comprising:

identifying, at a user equipment (UE), an indication of an amount of remaining energy for the UE or an indication of a temperature of the UE;

determining, by the UE, a constraint indicator based at least in part on the amount of remaining energy for the UE or the temperature of the UE;

transmitting, to a base station via physical layer signaling, the constraint indicator; and

receiving, from the base station, an indicator of an updated bandwidth for the UE to transmit signals to the base station or an indicator of an updated modulation and coding scheme (MCS) for communications between the UE and the base station, or both, wherein at least one of the updated bandwidth or the updated MCS is based at least in part on the constraint indicator.

2. The method of claim 1 , wherein transmitting the constraint indicator comprises:

transmitting the constraint indicator via a physical layer transmission comprising a channel quality indicator (CQI), rank index (RI), precoding matrix indicator (PMI), or any combination thereof.

3. The method of claim 1 , further comprising:

determining a first value for a channel quality indicator (CQI), rank index (RI), or precoding matrix indicator (PMI);

determining a second value for the CQI, RI, or PMI, the second value based at least in part on the amount of remaining energy for the UE or the temperature of the UE;

transmitting, to the base station via physical layer signaling, the first value for the CQI, RI, or PMI and the second value for the CQI, RI, or PMI; and

receiving, from the base station via physical layer signaling, an indicator of an updated value for the CQI, RI, or PMI that is based at least in part on the second value for the CQI, RI, or PMI.

4. The method of claim 1 ,

wherein the indicator of the updated MCS is received from the base station via physical layer signaling, and wherein the indicator of the updated MCS is based at least in part on an amount of pending data for the UE.

5. The method of claim 1 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of an updated rank index (RI) that is based at least in part on the constraint indicator, an amount of pending data for the UE, or any combination thereof.

6. The method of claim 1 , wherein the updated bandwidth comprises an updated number of component carriers (CCs) or bandwidth parts (BWPs).

7. The method of claim 1 , wherein the updated bandwidth comprises discontinuation of a dual connectivity configuration.

8. The method of claim 1 , further comprising:

determining, by the UE, an alternative bandwidth based at least in part on the amount of remaining energy for the UE or the temperature of the UE, wherein the alternative bandwidth comprises an alternative number of component carriers (CCs) or bandwidth parts (BWPs); and

transmitting, to the base station via physical layer signaling, an indicator of the alternative bandwidth.

9. The method of claim 1 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of an updated number of blind decodes to support that is based at least in part on the constraint indicator.

10. The method of claim 1 , further comprising:

determining, by the UE, an alternative number of blind decodes to support based at least in part on the amount of remaining energy for the UE or the temperature of the UE; and

transmitting, to the base station via physical layer signaling, an indicator of the alternative number of blind decodes to support.

11. The method of claim 1 , wherein determining the constraint indicator comprises:

selecting, from a set of discrete values, a discrete value for the constraint indicator.

12. The method of claim 1 , further comprising:

determining that the amount of remaining energy for the UE is below a threshold amount of remaining energy or that the temperature of the UE above a threshold temperature; and

determining to transmit the constraint indicator based at least in part on the amount of remaining energy for the UE being below the threshold amount of remaining energy or the temperature of the UE being above the threshold temperature.

13. The method of claim 12 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of the threshold amount of remaining energy or the threshold temperature.

14. The method of claim 1 , wherein:

the identifying comprises identifying the indication of the temperature of the UE; and

the constraint indicator is determined based at least in part on the temperature of the UE.

15. A method for wireless communications, comprising:

identifying, at a user equipment (UE), an indication of an amount of remaining energy for the UE or an indication of a temperature of the UE;

determining, by the UE, an alternative transmission mode, the alternative transmission mode comprising an alternative bandwidth for the UE to transmit signals or an alternative number of blind decodes to support, the alternative transmission mode based at least in part on the amount of remaining energy for the UE or the temperature of the UE; and

transmitting, to a base station via physical layer signaling, an indicator of the alternative transmission mode.

16. The method of claim 15 , wherein transmitting the indicator of the alternative transmission mode comprises:

transmitting the indicator of the alternative transmission mode via a physical layer transmission comprising a channel quality indicator (CQI), rank index (RI), precoding matrix indicator (PMI), or any combination thereof.

17. The method of claim 15 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of an updated bandwidth for the UE to transmit signals that is based at least in part on the indicator of the alternative transmission mode, an amount of pending data for the UE, or any combination thereof.

18. The method of claim 17 , wherein the updated bandwidth comprises an updated number of component carriers (CCs), an updated number of bandwidth parts (BWPs), or a discontinuation of a dual connectivity configuration.

19. The method of claim 15 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of an updated number of blind decodes to support that is based at least in part on the indicator of the alternative transmission mode, an amount of pending data for the UE, or any combination thereof.

20. The method of claim 15 , further comprising:

determining, by the UE, a constraint indicator based at least in part on the amount of remaining energy for the UE or the temperature of the UE;

transmitting, to the base station via physical layer signaling, the constraint indicator; and

receiving, from the base station via physical layer signaling, an indicator of an updated bandwidth for the UE to transmit signals or a number of blind decodes to support that is based at least in part on the constraint indicator.

21. The method of claim 15 , further comprising:

receiving, from the base station via physical layer signaling, an indicator of a threshold amount of remaining energy or a threshold temperature;

determining that the amount of remaining energy for the UE is below the threshold amount of remaining energy or that the temperature of the UE above the threshold temperature; and

determining to transmit the indicator of the alternative transmission mode based at least in part on the amount of remaining energy for the UE being below the threshold amount of remaining energy or the temperature of the UE being above the threshold temperature.

22. A method for wireless communications, comprising:

receiving, from a user equipment (UE) via physical layer signaling, a constraint indicator based at least in part on an amount of remaining energy for the UE or a temperature of the UE;

determining, based at least in part on the constraint indicator, an updated transmission mode for the UE, wherein the updated transmission mode comprises an updated bandwidth for the UE to transmit signals to the base station or an updated modulation and coding scheme (MCS) for communications between the UE and the base station, or both, and wherein at least one of the updated bandwidth or the updated MCS is based at least in part on the constraint indicator; and

transmitting, to the UE via physical layer signaling, an indicator of the updated transmission mode and one or more of an indicator of the updated bandwidth or an indicator of the updated MCS.

23. The method of claim 22 , further comprising:

receiving the constraint indicator via a physical layer transmission comprising a channel quality indicator (CQI), rank index (RI), precoding matrix indicator (PMI), or any combination thereof.

24. The method of claim 22 , further comprising:

receiving, from the UE via physical layer signaling, a first value for a channel quality indicator (CQI), rank index (RI), or precoding matrix indicator (PMI);

receiving, from the UE via physical layer signaling, a second value for the CQI, RI, or PMI, the second value for the CQI, RI, or PMI based at least in part on the amount of remaining energy for the UE or the temperature of the UE;

determining, based at least in part on the constraint indicator, an updated value for the CQI, RI, or PMI, the updated value for the CQI, RI, or PMI based at least in part on the second value for the CQI, RI, or PMI; and

transmitting, to the UE via physical layer signaling, the indicator of the updated value for the CQI, RI, or PMI.

25. The method of claim 22 , wherein determining the updated transmission mode comprises:

determining, based at least in part on the constraint indicator, an updated rank index (RI) for the UE that is based at least in part on an amount of pending data for the UE.

26. The method of claim 22 , wherein determining the updated transmission mode further comprises:

receiving, from the UE via physical layer signaling, an indicator of an alternative bandwidth that is based at least in part on the amount of remaining energy for the UE or the temperature of the UE; and

determining, based at least in part on the indicator of the alternative bandwidth, the updated bandwidth for the UE.

27. The method of claim 22 , wherein determining the updated transmission mode further comprises:

receiving, from the UE via physical layer signaling, an indicator of an alternative number of blind decodes for the UE to support that is based at least in part on the amount of remaining energy for the UE, the temperature of the UE, an amount of pending data for the UE, or any combination thereof; and

determining, based at least in part on the indicator of the alternative number of blind decodes for the UE to support, an updated number of blind decodes for the UE to support.

28. The method of claim 22 , wherein determining the updated transmission mode further comprises:

determining, for the UE, a threshold amount of remaining energy or a threshold temperature; and

configuring the UE to transmit the constraint indicator based at least in part on the amount of remaining energy for the UE being below the threshold amount of remaining energy or the temperature of the UE being above the threshold temperature.

29. A method for wireless communications, comprising:

receiving, from a user equipment (UE) via physical layer signaling, an indicator of an alternative transmission mode for the UE, the alternative transmission mode based at least in part on an amount of remaining energy for the UE or a temperature of the UE and comprising an alternative bandwidth for the UE to transmit signals or an alternative number of blind decodes to support;

determining, based at least in part on the indicator of the alternative transmission mode, an updated transmission mode for the UE, the updated transmission mode comprising an updated bandwidth for the UE to transmit signals or an updated number of blind decodes for the UE to support; and

transmitting, to the UE via physical layer signaling, an indicator of the updated transmission mode.

30. The method of claim 29 , wherein receiving the indicator of the alternative transmission mode comprises:

receiving the indicator of the alternative transmission mode via a physical layer transmission comprising a channel quality indicator (CQI), rank index (RI), precoding matrix indicator (PMI), or any combination thereof.