Data channel-referenced resource allocation for a control channel

1. A method for wireless communication, comprising:

identifying, for a transmission time interval (TTI), a first uplink frequency resource allocation to a user equipment (UE) of a first channel;

determining a modulation and coding scheme (MCS) index associated with the TTI;

determining, based at least in part on the first uplink frequency resource allocation of the first channel, a second uplink frequency resource allocation that is physically contiguous with the first uplink frequency resource allocation at least during a portion of the TTI;

selecting, based at least in part on the MCS index, a first waveform for the first channel and a second waveform for a second channel; and

transmitting, during the TTI, the first channel in the first uplink frequency resource allocation using the first waveform and the second channel in the second uplink frequency resource allocation using the second waveform.

2. The method of claim 1 , wherein the first channel is a data channel and the second channel is a control channel.

3. The method of claim 1 , wherein a size of the second uplink frequency resource allocation is determined based at least in part on a payload size of information carried on the second channel.

4. The method of claim 1 , wherein the second channel is mapped to a first frequency location for a first portion of the TTI and a second frequency location for a second portion of the TTI.

5. The method of claim 1 , wherein the determining of the second uplink frequency resource allocation comprises:

locating the second channel in a frequency resource adjacent to at least one of a lower boundary or an upper boundary of the first uplink frequency resource allocation.

6. The method of claim 1 , wherein a size of the second uplink frequency resource allocation of the second channel is determined based at least in part on at least one of an indication in a control channel, a size of the first uplink frequency resource allocation of the first channel, a location of the first uplink frequency resource allocation of the first channel, a format of the second channel, a duration of the TTI, or a combination thereof.

7. The method of claim 1 , wherein information of a first type is mapped to the first channel and information of a second type is mapped to the second channel.

8. The method of claim 7 , wherein the information of the first type comprises data and the information of the second type comprises uplink control information.

9. The method of claim 8 , further comprising:

mapping a first portion of the uplink control information to the first channel; and

mapping a second portion of the uplink control information to the second channel.

10. The method of claim 1 , further comprising:

receiving an allocation message indicating the first uplink frequency resource allocation and a number of subcarriers for the second channel.

11. The method of claim 1 , further comprising:

receiving an allocation message indicating the first uplink frequency resource allocation.

12. The method of claim 1 , wherein the first uplink frequency resource allocation has a first granularity and the second uplink frequency resource allocation has a second granularity different from the first granularity.

13. The method of claim 1 , wherein the second channel is orthogonalized to a channel for at least one other UE transmitted in at least a portion of the second uplink frequency resource allocation using a spreading code or a precoding matrix.

14. The method of claim 1 , wherein the determining of the second uplink frequency resource allocation comprises:

locating the second channel in a frequency resource interposed within the first uplink frequency resource allocation.

15. The method of claim 14 , wherein the second channel is not adjacent to a lower frequency boundary or an upper frequency boundary of the first uplink frequency resource allocation.

16. The method of claim 1 , wherein the transmitting, during the TTI, the first channel and the second channel comprises:

generating a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform for the first channel, wherein the first waveform comprises the CP-OFDM waveform; and

generating a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform for the second channel, wherein the second waveform comprises the DFT-S-OFDM waveform.

17. The method of claim 1 , wherein the transmitting, during the TTI, the first channel and the second channel comprises:

generating a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform for the first channel, wherein the first waveform comprises the DFT-S-OFDM waveform; and

generating a second DFT-S-OFDM waveform for the second channel, wherein the second waveform comprises the second DFT-S-OFDM waveform.

18. The method of claim 1 , further comprising:

determining that the UE is to use a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform or a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform during a second TTI;

determining to multiplex data information with control information into the first channel for the second TTI; and

transmitting, during the second TTI, the multiplexed data and control information in the first channel using the DFT-S-OFDM waveform or the CP-OFDM waveform.

19. The method of claim 1 , wherein the transmitting, during the TTI, the first channel and the second channel comprises:

determining, for the first channel, a plurality of precoding matrices associated with a plurality of layers for the TTI;

applying the plurality of precoding matrices to precode information of a first type for transmission of the first channel over the plurality of layers; and

applying one of the plurality of precoding matrices to precode information of a second type for transmission of the second channel over one of the plurality of layers.

20. The method of claim 1 , wherein transmitting, during the TTI, the first channel and the second channel comprises:

time-division multiplexing the first channel with the second channel during the TTI.

21. The method of claim 20 , further comprising:

determining to time-division multiplex the first channel with the second channel based at least in part on a duration of the TTI, a size of the first uplink frequency resource allocation of the first channel, a payload size of information carried on the second channel, or combinations thereof.

22. An apparatus for wireless communication, in a system comprising:

a processor;

memory coupled with the processor; and

instructions stored in the memory and operable, when executed by the processor, to cause the apparatus to:

identify, for a transmission time interval (TTI), a first uplink frequency resource allocation to a user equipment (UE) of a first channel;

determine a modulation and coding scheme (MCS) index associated with the TTI;

determine, based at least in part on the first uplink frequency resource allocation of the first channel, a second uplink frequency resource allocation that is physically contiguous with the first uplink frequency resource allocation at least during a portion of the TTI;

selecting, based at least in part on the MCS index, a first waveform for the first channel and a second waveform for a second channel; and

transmit, during the TTI, the first channel in the first uplink frequency resource allocation using the first waveform and the second channel in the second uplink frequency resource allocation using the second waveform.

23. The apparatus of claim 22 , further comprising instructions that, when executed by the processor, cause the apparatus to:

locate the second channel in a frequency resource adjacent to at least one of a lower boundary or an upper boundary of the first uplink frequency resource allocation.

24. The apparatus of claim 22 , further comprising instructions that, when executed by the processor, cause the apparatus to:

map information of a first type to the first channel and information of a second type to the second channel.

25. The apparatus of claim 22 , wherein the instructions when executed by the processor to cause the apparatus to determine the second uplink frequency resource allocation further comprise instructions that, when executed by the processor, cause the apparatus to:

locate the second channel in a frequency resource interposed within the first uplink frequency resource allocation.

26. The apparatus of claim 22 , further comprising instructions that, when executed by the processor, cause the apparatus to:

generate a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform for the first channel, wherein the first waveform comprises the CP-OFDM waveform; and

generate a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform for the second channel, wherein the second waveform comprises the DFT-S-OFDM waveform.

27. The apparatus of claim 22 , further comprising instructions that, when executed by the processor, cause the apparatus to:

generate a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform for the first channel, wherein the first waveform comprises the DFT-S-OFDM waveform; and

generate a second DFT-S-OFDM waveform for the second channel, wherein the second waveform comprises the second DFT-S-OFDM waveform.

28. The apparatus of claim 22 , further comprising instructions that, when executed by the processor, cause the apparatus to:

determine that the UE is to use a discrete Fourier transform spread orthogonal frequency division multiplexing (DFT-S-OFDM) waveform or a cyclic prefix orthogonal frequency division multiplexing (CP-OFDM) waveform during a second TTI;

determine to multiplex data information with control information into the first channel for the second TTI; and

transmit, during the second TTI, the multiplexed data and control information in the first channel using the DFT-S-OFDM waveform or the CP-OFDM waveform.

29. An apparatus for wireless communication, comprising:

means for identifying, for a transmission time interval (TTI), a first uplink frequency resource allocation to a user equipment (UE) of a first channel;

means for determining a modulation and coding scheme (MCS) index associated with the TTI;

means for determining, based at least in part on the first uplink frequency resource allocation of the first channel, a second uplink frequency resource allocation that is physically contiguous with the first uplink frequency resource allocation at least during a portion of the TTI;

means for selecting, based at least in part on the MCS index, a first waveform for the first channel and a second waveform for a second channel; and

means for transmitting, during the TTI, the first channel in the first uplink frequency resource allocation using the first waveform and the second channel in the second uplink frequency resource allocation using the second waveform.

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

identify, for a transmission time interval (TTI), a first uplink frequency resource allocation to a user equipment (UE) of a first channel;

determine a modulation and coding scheme (MCS) index associated with the TTI;

determine, based at least in part on the first uplink frequency resource allocation of the first channel, a second uplink frequency resource allocation that is physically contiguous with the first uplink frequency resource allocation at least during a portion of the TTI;

selecting, based at least in part on the MCS index, a first waveform for the first channel and a second waveform for a second channel; and

transmit, during the TTI, the first channel in the first uplink frequency resource allocation using the first waveform and the second channel in the second uplink frequency resource allocation using the second waveform.