Index modulation for low-power analog-to-digital converters

A method for wireless communications at a base station, comprising:

• receiving, from a user equipment (UE), a first message comprising an indication of a quantity of subcarriers, the quantity of subcarriers being from a plurality of subcarriers within a bandwidth, wherein the quantity of subcarriers is based at least in part on a signal-to-quantization-noise ratio, a signal-to-noise ratio, one or more power consumption factors of the UE, or any combination thereof;
• determining, based at least in part on the indication of the quantity of subcarriers, a quantity of active subcarriers of the plurality of subcarriers for index modulated communications with the UE;
• and
• transmitting, to the UE, a second message comprising an indication of the quantity of active subcarriers.

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:
• identify, from a plurality of subcarriers within a bandwidth, a quantity of subcarriers for index modulated communications, the quantity of subcarriers being identified based at least in part on a signal-to-quantization-noise ratio, a signal-to-noise ratio, one or more power consumption factors of the UE, or any combination thereof;
• transmit, to a base station, a first message comprising an indication of the quantity of subcarriers;
• and
• process an index modulated downlink signal based at least in part on the quantity of subcarriers.

An apparatus for wireless communications at a base station, 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 user equipment (UE), a first message comprising an indication of a quantity of subcarriers, the quantity of subcarriers being from a plurality of subcarriers within a bandwidth, wherein the quantity of subcarriers is based at least in part on a signal-to-quantization-noise ratio, a signal-to-noise ratio, one or more power consumption factors of the UE, or any combination thereof;
• determine, based at least in part on the indication of the quantity of subcarriers, a quantity of active subcarriers of the plurality of subcarriers for index modulated communications with the UE;
• and
• transmit, to the UE, a second message comprising an indication of the quantity of active subcarriers.