US Patent 9998187 System and method for combining MIMO and mode-division multiplexing

A communications system includes first signal processing circuitry for receiving a plurality of input data streams and applying a different orthogonal function to each of the plurality of input data streams. Second signal processing circuitry processes each of the plurality of input data streams having the different orthogonal function applied thereto to locate a first group of the plurality of input data streams having a first orthogonal function applied thereto onto a carrier signal and locates a second group of the plurality of input data streams having a second orthogonal function applied thereto onto the carrier signal. A transmitter transmits the carrier signal including the first group of the plurality of input data streams having the first orthogonal function applied thereto and the second group of the plurality of input data streams having the second orthogonal function applied thereto over a plurality of communications links from a plurality of transmitting antennas.