Low RCS Automotive Radar Antenna with Beam Steering Capability

Automotive radar antennas are one of the frontier areas of research in modern automotive vehicle industries and are employed for applications, viz., adaptive cruise control (ACC), collision warning (CW), blind spot detection, parking assistance etc. The futuristic automotive vehicles used in hostile areas in combat-type situations led to the design and development of stealth vehicles. The antennas mounted on automotive vehicles operate in mm wave frequency range with a high gain. In this document, an automotive patch array is designed at 78.84 GHz with High Impedance Surface (HIS)-based reduced ground plane. The main objective is to achieve significant reduction in structural RCS of array without any degradation in radiation performance. Furthermore, a microstrip to waveguide transition feed has been integrated in the automotive patch array to enhance the radiation performance of the antenna. Reduced ground plane has been employed to achieve RCS reduction. Apart from reduced antenna scattering, there is a need of beam scanning to sense different obstacles at different positions around the vehicle. In this work, a passive beam steering technique has been implemented by introducing delay lines in the antenna array structure.