Reconfigurable multi-beam pillbox antenna for millimeter wave automotive radars

This work proposes a multi-layer multi-beam reconfigurable pillbox antenna based on a novel transition between two substrates working as a quasi-optical system. The antenna consists of three main parts that can be designed and optimized independently: feeding part, quasi-optical system and radiating part. The novel quasi-optical system is made by several slots etched in the common metal layer and located along the entire length of an integrated parabolic reflector made by vertical metallic pins. The quasi-optical system shapes and focuses the energy traveling inside the lower layer to the radiating part made by an array of slotted waveguides. Several integrated horns placed in the focal plane of the integrated parabolic reflector are used to feed the quasi-optical system. Thanks to this feeding solution and the introduced quasi-optical system, multi-beam operation and beam reconfiguration capability on a wide angle field of view are achieved. The proposed structure is compatible with low-cost printed circuit board and substrate integrated waveguide technology. The low profile, low cost, efficiency and pattern reconfigurability of the proposed antenna make it very promising for the next generation of automotive radars.