Unsourced random access via channel clustering in orthogonal time frequency space domain

A method for wireless communications at a first wireless device, comprising:

• obtaining, from a plurality of second wireless devices, a plurality of message segments via a plurality of slots;
• assigning each message segment of the plurality of message segments to a respective delay-Doppler (DD) domain cluster of a plurality of DD domain clusters based at least in part on respective message segments of the respective DD domain clusters having similar time delay and Doppler shift characteristics, wherein a first plurality of message segments of the plurality of message segments associated with a first DD domain cluster of the plurality of DD domain clusters collectively forms a first message associated with unsourced random access operations corresponding to a second wireless device of the plurality of second wireless devices;
• and
• decoding the first message comprising the first plurality of message segments based at least in part on a codebook shared with the plurality of second wireless devices, the codebook based at least in part on a quantity of delay bins and a quantity of Doppler bins.

A first wireless device for wireless communications, comprising:

• means for obtaining, from a plurality of second wireless devices, a plurality of message segments via a plurality of slots;
• means for assigning each message segment of the plurality of message segments to a respective delay-Doppler (DD) domain cluster of a plurality of DD domain clusters based at least in part on respective message segments of the respective DD domain clusters having similar time delay and Doppler shift characteristics, wherein a first plurality of message segments of the plurality of message segments associated with a first DD domain cluster of the plurality of DD domain clusters collectively forms a first message associated with unsourced random access operations corresponding to a second wireless device of the plurality of second wireless devices;
• and
• means for decoding the first message comprising the first plurality of message segments based at least in part on a codebook shared with the plurality of second wireless devices, the codebook based at least in part on a quantity of delay bins and a quantity of Doppler bins.

A non-transitory computer-readable medium storing code for wireless communications, the code comprising instructions executable by one or more processors to:

• obtain, from a plurality of second wireless devices, a plurality of message segments via a plurality of slots;
• assign each message segment of the plurality of message segments to a respective delay-Doppler (DD) domain cluster of a plurality of DD domain clusters based at least in part on respective message segments of the respective DD domain clusters having similar time delay and Doppler shift characteristics, wherein a first plurality of message segments of the plurality of message segments associated with a first DD domain cluster of the plurality of DD domain clusters collectively forms a first message associated with unsourced random access operations corresponding to a second wireless device of the plurality of second wireless devices;
• and
• decode the first message comprising the first plurality of message segments based at least in part on a codebook shared with the plurality of second wireless devices, the codebook based at least in part on a quantity of delay bins and a quantity of Doppler bins.