A Compact Lens-Primary Source Structure for Avoidance Radar System

The design and realisation of a compact structure that includes an artificial lens and a primary source in planar technology is presented. Such structure is the RF part of a monopulse radar system to detect obstacles in front of a vehicle. First, the feasibility of such compact structure is implemented at 32 GHz for which the lens is built using a stack of parallel-plate waveguides using foam technology (low-loss dielectric material with relative permittivity close to one). Extension to 76 GHz requires the primary source feeding to use branch coupler technique and the radiating element in membrane technology. Alternate original structures are implemented at 32 GHz tested and compared with the model. Results show that the proposed structure meets the requirements and that models used for the design are generally in good agreement with measurements.