Power amplifier compressed reference signals for digital post distortion detection

1 . A method for wireless communication at a base station, comprising:

transmitting a set of reference signals to a user equipment (UE), the set of reference signals comprising a power amplifier uncompressed reference signal and a subset of compressed reference signals that are compressed with respective levels of power amplifier compression;

receiving a channel state report from the UE comprising channel state feedback associated with the power amplifier uncompressed reference signal and each reference signal of the subset of compressed reference signals;

selecting a power amplifier compression level for communications with the UE based at least in part on the channel state report; and

communicating with the UE according to the selected power amplifier compression level.

2 . The method of claim 1 , further comprising:

comparing channel state feedback of at least one reference signal of the subset of compressed reference signals to channel state feedback of the power amplifier uncompressed reference signal; and

determining, based at least in part on a result of the comparing, a highest level of power amplifier compression that the UE is capable of processing of the respective levels of power amplifier compression.

3 . The method of claim 2 , wherein determining the highest level of power amplifier compression that the UE is capable of processing comprises:

determining that the UE is capable of processing channel state feedback of a first reference signal of the subset of compressed reference signals associated with a first level of power amplifier compression;

determining that the UE is not capable of processing channel state feedback of a second reference signal of the subset of compressed reference signals associated with a second level of power amplifier compression; and

selecting the first level of power amplifier compression as the highest level of power amplifier compression that the UE is capable of processing of the respective levels of power amplifier compression.

4 . The method of claim 3 , wherein the second level of power amplifier compression is a next highest level of power amplifier compression above the first level of power amplifier compression of the respective levels of power amplifier compression.

5 . The method of claim 2 , wherein the highest level of power amplifier compression that the UE is capable of processing is based at least in part on a coefficient of a digital post distortion model supported by the UE.

6 . The method of claim 1 , wherein the selected power amplifier compression level is selected from the respective levels of power amplifier compression of the subset of compressed reference signals.

7 . The method of claim 1 , wherein the channel state feedback comprises a pre-coding matrix indicator, a channel quality indicator, or a rank indicator, or any combination thereof.

8 . The method of claim 1 , wherein the set of reference signals include channel state information reference signals.

9 . The method of claim 1 , wherein the set of reference signals are transmitted periodically or aperiodically.

10 . The method of claim 1 , wherein the power amplifier uncompressed reference signal is transmitted by a transmitter of the base station while a power amplifier of the transmitter is operating in a linear region.

11 . The method of claim 1 , wherein the subset of compressed reference signals is transmitted by a transmitter of the base station while a power amplifier of the transmitter is operating in a compression region.

12 . A method for wireless communication at a user equipment (UE), comprising:

receiving, from a base station, a set of reference signals comprising a power amplifier uncompressed reference signal and a subset of compressed reference signals that are compressed with respective levels of power amplifier compression;

performing a channel state measurement on each reference signal of the set of reference signals;

transmitting, to the base station based at least in part on the channel state measurement performed on each reference signal, a channel state report comprising channel state feedback associated with each reference signal of the subset of compressed reference signals and the power amplifier uncompressed reference signal; and

communicating with the base station based at least in part on a power amplifier compression level that is implemented in accordance with the channel state report.

13 . The method of claim 12 , wherein performing the channel state measurement on each reference signal of the set of reference signals comprises:

estimating the channel state feedback of each reference signal of the set of reference signals, the channel state feedback including a pre-coding matrix indicator, a channel quality indicator, a rank indicator, or a modulation and coding scheme value, or any combination thereof.

14 . The method of claim 12 , wherein communicating with the base station comprises:

receiving a signal from the base station that is compressed with the power amplifier compression level that is implemented in accordance with the channel state report; and

applying digital post distortion reduction to the received signal based at least in part on a digital post distortion model supported by the UE.

15 . The method of claim 14 , wherein applying digital post distortion reduction is based at least in part on coefficients of the digital post distortion model that are supported by the UE.

16 . The method of claim 15 , wherein the power amplifier compression level that is implemented in accordance with the channel state report is based at least in part on the coefficients of the digital post distortion model, the coefficients including one or more weights of a Volterra filter.

17 . The method of claim 12 , wherein the set of reference signals are received periodically or aperiodically.

18 . The method of claim 12 , wherein transmission of the power amplifier uncompressed reference signal is based at least in part on a power amplifier of the base station operating in a linear region.

19 . The method of claim 12 , wherein transmission of the subset of compressed reference signals is based at least in part on a power amplifier of the base station operating in a compression region.

20 . An apparatus for wireless communication at a base station, comprising:

a processor;

a memory coupled with the processor, wherein the memory comprises instructions executable by the processor to cause the apparatus to:

transmit a set of reference signals to a user equipment (UE), the set of reference signals comprising a power amplifier uncompressed reference signal and a subset of compressed reference signals that are compressed with respective levels of power amplifier compression;

receive a channel state report from the UE comprising channel state feedback associated with the power amplifier uncompressed reference signal and each reference signal of the subset of compressed reference signals;

select a power amplifier compression level for communications with the UE based at least in part on the channel state report; and

communicate with the UE according to the selected power amplifier compression level.

21 . The apparatus of claim 20 , wherein the instructions are further executable by the processor to cause the apparatus to:

compare channel state feedback of at least one reference signal of the subset of compressed reference signals to channel state feedback of the power amplifier uncompressed reference signal; and

determine, based at least in part on a result of the comparing, a highest level of power amplifier compression that the UE is capable of processing of the respective levels of power amplifier compression.

22 . The apparatus of claim 21 , wherein the instructions to determine the highest level of power amplifier compression that the UE is capable of processing are executable by the processor to cause the apparatus to:

determine that the UE is capable of processing channel state feedback of a first reference signal of the subset of compressed reference signals associated with a first level of power amplifier compression;

determine that the UE is not capable of processing channel state feedback of a second reference signal of the subset of compressed reference signals associated with a second level of power amplifier compression; and

select the first level of power amplifier compression as the highest level of power amplifier compression that the UE is capable of processing of the respective levels of power amplifier compression.

23 . The apparatus of claim 22 , wherein the second level of power amplifier compression is a next highest level of power amplifier compression above the first level of power amplifier compression of the respective levels of power amplifier compression.

24 . The apparatus of claim 21 , wherein the highest level of power amplifier compression that the UE is capable of processing is based at least in part on a coefficient of a digital post distortion model supported by the UE.

25 . The apparatus of claim 20 , wherein the selected power amplifier compression level is selected from the respective levels of power amplifier compression of the subset of compressed reference signals.

26 . The apparatus of claim 20 , wherein the channel state feedback comprises a pre-coding matrix indicator, a channel quality indicator, or a rank indicator, or any combination thereof.

27 . The apparatus of claim 20 , wherein: the set of reference signals includes channel state information reference signals.

28 . The apparatus of claim 20 , wherein: the set of reference signals are transmitted periodically or aperiodically.

29 . The apparatus of claim 20 , wherein the power amplifier uncompressed reference signal is transmitted by a transmitter of the base station while a power amplifier of the transmitter is operating in a linear region.

30 . An apparatus for wireless communication at a user equipment (UE), comprising:

a processor;

a memory coupled with the processor, wherein the memory comprises instructions executable by the processor to cause the apparatus to:

receive, from a base station, a set of reference signals comprising a power amplifier uncompressed reference signal and a subset of compressed reference signals that are compressed with respective levels of power amplifier compression;

perform a channel state measurement on each reference signal of the set of reference signals;

transmit, to the base station based at least in part on the channel state measurement performed on each reference signal, a channel state report comprising channel state feedback associated with each reference signal of the subset of compressed reference signals and the power amplifier uncompressed reference signal; and

communicate with the base station based at least in part on a power amplifier compression level that is implemented in accordance with the channel state report.