Techniques for partial transmit sequence transmission using multi-mode index modulation

An apparatus for wireless communication at a wireless device, 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 a first plurality of bits of information bits of a signal, the first plurality of bits indicating an index associated with a second plurality of bits of the information bits of the signal;
• identify the second plurality of bits, wherein the second plurality of bits includes a first group of bits and a second group of bits;
• obtain a plurality of candidate partial transmit sequences based at least in part on a first phase rotation applied to a first output of an inverse Fast Fourier Transform of the first group of bits and a second phase rotation applied to a second output of an inverse Fast Fourier Transform of the second group of bits, the first group of bits and the second group of bits having a same size;
• and
• transmit the signal based at least in part on selecting a partial transmit sequence from the plurality of candidate partial transmit sequences.

An apparatus for wireless communication, 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 a first plurality of bits and a second plurality of bits in accordance with a partial transmit sequence, the first plurality of bits indicating an index associated with the second plurality of bits in at least one subcarrier, and the second plurality of bits including a first group of bits and a second group of bits;
• and
• combine the first plurality of bits and the second plurality of bits based at least in part on the partial transmit sequence to obtain information bits of a signal.