NEW TECHNIQUE TO SUPPRESS SIDELOBE CLUTTER IN PERIMETER SECURITY SYSTEMS

Abstract

False echoes degrade the operation of radar and imaging antennas. The false returns or clutter arise from antenna sidelobes and raise the threshold of detection in perimeter security systems. Accordingly there is great interest in reducing the sidelobes in present day millimeter wave and future terahertz antennas. Here we describe a new technique to suppress antenna sidelobe returns. The technique exploits our ability to distinguish between the phase of desired signals arriving in the antenna main beam and the phase of undesired clutter signals coming from the sidelobes. We demonstrate that through modulation of phase and taking the Fourier transform of the received signal, we can preferentially suppress the clutter return relative to the desired main beam signal. Suppression of average clutter return of over 25 dB is found.