3D Radar Localization via Photonic Chirp Leaky-Wave Antenna Beam Scanning

Abstract

We report a photonic frequency-modulated continuous wave (FMCW) radar system that provides 3D localization with a simple radar frontend. This is achieved by exploiting linearly polarized leaky-wave antennas (LWAs) for simultaneously scanning azimuth and elevation. As such, the FMCW frequency sweep is employed for radar operation as well as LWA beam steering for target angle estimation. The LWAs are based on series fed patches and provide beam steering from -20.7° to +18° in the frequency range of 24-33 GHz in the H-plane and a field of view from -18.9° to 33.3° in the E-plane. The FMCW signal is photonically generated from the wavelength chirp of a low-cost DFB laser. Coherent radio-over-fiber transport with photonic upconversion provides low loss distribution and frequency scaling. Finally, 3D radar localization is experimentally demonstrated by two orthogonal LWAs. A ranging accuracy of better than 4 cm and an angular accuracy of ^\circ$ have been achieved without any dedicated radar post processing.