Low latency uplink acknowledgement channel waveform design

1. A method for wireless communication, comprising:

receiving a transmission in a transmission time interval (TTI);

identifying an uplink (UL) acknowledgement (ACK) channel configuration based at least in part on a format of the TTI, wherein the UL ACK channel configuration includes at least an interleaved frequency division multiple access (iFDMA) waveform; and

sending an ACK message via an UL ACK channel according to the identified UL ACK channel configuration.

2. The method of claim 1 , wherein the format of the TTI comprises a plurality of symbols for the transmission.

3. The method of claim 2 , further comprising:

decoding a first symbol of the plurality of symbols in the transmission in the TTI; and

scheduling at least a portion of a resource associated with conveying the ACK message prior to decoding a second symbol of the plurality of symbols in the transmission in the TTI.

4. The method of claim 3 , further comprising:

utilizing the resource to send at least a portion of the ACK message prior to receiving each of the symbols of the plurality of symbols in the transmission.

5. The method of claim 4 , wherein the portion of the ACK message comprises at least pilot information, or channel space feedback information, or ACK/negative ACK (ACK/NACK) information, or a combination thereof.

6. The method of claim 2 , further comprising:

sending the ACK message in more than one symbol in a subsequent TTI.

7. The method of claim 2 , further comprising:

determining that the transmission in the TTI is associated with a high priority communication.

8. The method of claim 1 , wherein the format of the TTI comprises one symbol.

9. The method of claim 8 , further comprising:

identifying a communication metric associated with the ACK message; and

selecting a non-zero tone value for the iFDMA waveform based at least in part on the communication metric, the non-zero tone value corresponding to a number of non-zero tones within a predetermined number of tones of the iFDMA waveform.

10. The method of claim 9 , wherein the iFDMA waveform is multiplexed with one or more other iFDMA waveforms to capture orthogonality and spectrum efficiency.

11. The method of claim 9 , wherein the communication metric comprises at least a latency attribute associated with the ACK message, or a frequency diversity attribute associated with the ACK message, or a peak to average power ratio (PAPR) attribute associated with the ACK message, or a combination thereof.

12. The method of claim 8 , further comprising:

determining that the transmission received in the TTI is associated with a high priority communication.

13. An apparatus for wireless communication, comprising:

a processor;

memory in electronic communication with the processor; and

instructions stored in the memory, the instructions being executable by the processor to: receive a transmission in a transmission time interval (TTI);

identify an uplink (UL) acknowledgement (ACK) channel configuration based at least in part on a format of the TTI, wherein the UL ACK channel configuration includes at least an interleaved frequency division multiple access (iFDMA) waveform; and

send an ACK message via an UL ACK channel according to the identified UL ACK channel configuration.

14. The apparatus of claim 13 , wherein the format of the TTI comprises a plurality of symbols for the transmission.

15. The apparatus of claim 14 , further comprising instructions executable by the processor to:

decode a first symbol of the plurality of symbols in the transmission in the TTI; and

schedule at least a portion of a resource associated with conveying the ACK message prior to decoding a second symbol of the plurality of symbols in the transmission in the TTI.

16. The apparatus of claim 15 , further comprising instructions executable by the processor to:

utilize the resource to send at least a portion of the ACK message prior to receiving each of the symbols of the plurality of symbols in the transmission.

17. The apparatus of claim 16 , wherein the portion of the ACK message comprises at least pilot information, or channel space feedback information, or ACK/negative ACK (ACK/NACK) information, or a combination thereof.

18. The apparatus of claim 14 , further comprising instructions executable by the processor to:

send the ACK message in more than one symbol in a subsequent TTI.

19. The apparatus of claim 14 , further comprising instructions executable by the processor to:

determine that the transmission in the TTI is associated with a high priority communication.

20. The apparatus of claim 13 , wherein the format of the TTI comprises one symbol.

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

identify a communication metric associated with the ACK message; and

select a non-zero tone value for the iFDMA waveform based at least in part on the communication metric, the non-zero tone value corresponding to a number of non-zero tones within a predetermined number of tones of the iFDMA waveform.

22. The apparatus of claim 21 , wherein the iFDMA waveform is multiplexed with one or more other iFDMA waveforms to capture orthogonality and spectrum efficiency.

23. The apparatus of claim 21 , wherein the communication metric comprises at least a latency attribute associated with the ACK message, or a frequency diversity attribute associated with the ACK message, or a peak to average power ratio (PAPR) attribute associated with the ACK message, or a combination thereof.

24. The apparatus of claim 20 , further comprising instructions executable by the processor to:

determine that the transmission received in the TTI is associated with a high priority communication.

25. An apparatus for wireless communication, comprising:

means for receiving a transmission in a transmission time interval (TTI);

means for identifying an uplink (UL) acknowledgement (ACK) channel configuration based at least in part on a format of the TTI, wherein the UL ACK channel configuration includes at least an interleaved frequency division multiple access iFDMA waveform; and

means for sending an ACK message via an UL ACK channel according to the identified UL ACK channel configuration.

26. The apparatus of claim 25 , wherein the format of the TTI comprises a plurality of symbols for the transmission.

27. The apparatus of claim 26 , further comprising:

means for decoding a first symbol of the plurality of symbols in the transmission in the TTI; and

means for scheduling at least a portion of a resource associated with conveying the ACK message prior to decoding a second symbol of the plurality of symbols in the transmission in the TTI.

28. A non-transitory computer-readable medium storing computer-executable code for wireless communication, the code executable by a processor to:

receive a transmission in a transmission time interval (TTI);

identify an uplink (UL) acknowledgement (ACK) channel configuration based at least in part on a format of the TTI, wherein the UL ACK channel configuration includes at least an interleaved frequency division multiple access (iFDMA) waveform; and

send an ACK message via an UL ACK channel according to the identified UL ACK channel configuration.