Random noise radar interferometry

A novel technique has been developed to inject coherence in an ultrawideband radar system that transmits white Gaussian random noise. Coherence is introduced in the system by performing heterodyne correlation of the received signal with the time-delayed replica of the transmit signal. This operation preserves the phase of the reflected signal which is lost in a traditional homodyne correlation receiver. Knowledge of the phase of the received signal permits the configuration of the system as a spaced antenna interferometer for azimuthal scanning and transversal speed estimation. This paper describes the basic theory of random noise radar interferometry, and presents first results obtained using the University of Nebraska's 1-2 GHz random noise radar system configured as a radar interferometer.