US 2019/0238367 A1 · REFERENCE SIGNAL TRANSMISSION TECHNIQUES FOR NON-ORTHOGONAL MULTIPLE ACCESS WIRELESS COMMUNICATIONS

Abstract

Methods, systems, and devices for wireless communications are described that provide for concurrent reference signal transmissions using common resources, such as demodulation reference signal (DMRS) transmissions, from a number of non-orthogonal multiple access (NOMA) transmitters. Different transmitters may use different sequences for reference signal transmissions, which may allow a receiver, such as a wireless base station, to decode the reference signal transmissions for each NOMA transmitter and perform channel estimation for each NOMA transmitter. The reference signal transmissions may be asynchronous with a bounded timing offset or quasi-synchronous, and the reference signal sequence selection may provide for relatively reliable channel estimation and coherent demodulation.

Claims30

Dependent claims

A method for wireless communication, comprising:

receiving, from a base station, an indication of a set of resources for transmission of a reference signal, wherein a plurality of non-orthogonal multiple access (NOMA) transmitters are configured for at least partially concurrent transmissions using the set of resources;
identifying, based at least in part on the set of resources, a plurality of short sequences to be included in the reference signal, each short sequence of the plurality of short sequences having a root index and cyclic shift that provides a cross-correlation with other of the plurality of short sequences that is below a threshold value;
concatenating the plurality of short sequences to generate a reference signal sequence for the reference signal;
and
transmitting the reference signal to the base station.

2 more elements

An apparatus for wireless communication, comprising:

a processor;
memory in electronic communication with the processor;
and
instructions stored in the memory and executable by the processor to cause the apparatus to:
receive, from a base station, an indication of a set of resources for transmission of a reference signal, wherein at least one non-orthogonal multiple access (NOMA) transmitter associated with the apparatus is configured for at least partially concurrent transmissions using the set of resources;
identify, based at least in part on the set of resources, a plurality of short sequences to be included in the reference signal, each short sequence of the plurality of short sequences having a root index and cyclic shift that provides a cross-correlation with other of the plurality of short sequences that is below a threshold value;
concatenate the plurality of short sequences to generate a reference signal sequence for the reference signal;
and
transmit the reference signal to the base station.

6 more elements

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

receive, from a base station, an indication of a set of resources for transmission of a reference signal, wherein at least one non-orthogonal multiple access (NOMA) transmitter operatively coupled to the processor is configured for at least partially concurrent transmissions using the set of resources;
identify, based at least in part on the set of resources, a plurality of short sequences to be included in the reference signal, each short sequence of the plurality of short sequences having a root index and cyclic shift that provides a cross-correlation with other of the plurality of short sequences that is below a threshold value;
concatenate the plurality of short sequences to generate a reference signal sequence for the reference signal;
and
transmit the reference signal to the base station.

2 more elements

Dependencies are inferred from the claim text.

Reference signal transmission techniques for non-orthogonal multiple access wireless communications

Life of this patent

Reference signal transmission techniques for non-orthogonal multiple access wireless communications

Life of this patent

Abstract

Claims30