Patent ID: 9103904
Filing Date: 2015-08-11
Classification: G01S

Abstract:
1. A Doppler system for detecting an object, comprising: a continuous millimeter or terahertz wave source; a millimeter or terahertz wave beam splitter positioned to receive a continuous millimeter or terahertz wave beam from the continuous millimeter or terahertz wave source and split the beam into an object beam directed to the object and a reference beam directed to a smooth phase modulator; the smooth phase modulator with modulation frequency larger than twice the Doppler frequency of the object; the reference beam having a Low-Frequency-Band (LFB) Doppler signature modulated to a High-Frequency-Band (HFB) Doppler centered at a reference frequency of the smooth phase modulator; a reflected signal from the object having a determined amplitude and phase; and a millimeter or terahertz wave intensity detector positioned to receive the modulated reference beam and the reflected signal; wherein the Doppler frequency signature of the object is determined based upon the determined amplitude and phase and each higher-order harmonic High-Frequency-Bands (HFBs) of the reference frequency is recognized.