CPC G01S 7/35 (2013.01)  10 Claims 
1. A doppler division multiplexing (DDM) multiple input multiple output (MIMO) radar system comprising a transmitter connected to an antenna assembly having a set of N antennas via a corresponding set of N signal paths of different electrical lengths, where N is an integer greater than one;
wherein the transmitter is configured to generate a series of M chirps in a radar cycle frame and to provide each chirp to each antenna of the antenna assembly, where M is an integer greater than one;
wherein each chirp in the series of M chirps has a corresponding center frequency, the corresponding center frequency changing between successive chirps;
wherein the corresponding center frequency of the first chirp in the series of M chirps in the radar cycle frame is a first center frequency that corresponds to a first wavelength (λ_{1});
wherein the antenna assembly is dimensioned such that, at the first center frequency, the electrical lengths of the set of N signal paths differ from each other by integer multiples of the first wavelength; and
wherein the antenna assembly is further dimensioned such that, when the radar system transmits each chirp of the series of M chirps in the radar cycle frame, a corresponding pattern of phase differences between each of the antennas at the center frequency of that chirp is different from corresponding patterns of phase differences between each of the antennas arms for each other chirp of the series of M chirps.
