US Patent 11768291 High dynamic range ranging interferometer

Systems and methods for measuring relative velocities of platforms are provided. More particularly, light of a single wavelength is directed from a primary platform to a secondary platform as a probe signal. A shift in the frequency of the probe signal caused by a different relative velocity of the platforms is measured. The measurement is performed by using a heterodyne signal produced by mixing the return signal with light at a plurality of different, evenly spaced frequencies, provided from a local oscillator in the form of a frequency comb generator. This configuration enables precise measurements of relative velocity over wide range of velocities.