Planar Multiresolutional Antenna for Automotive Radar

High resolution and wide angle surveying capability are combined within a single planar antenna system using a modified Rotman-lens. While narrow beam mode is achieved by feeding the beamports of the lens, broad beams are realized by distributed sidewall feeding with secondary lenses. A Fresnel-lens-like delay network is introduced in the design to reduce the sidelobe level. Effects of fabrication tolerances are assessed. The concept is validated experimentally.