Compact quasi-optical focusing system for a 94 GHz FMCW radar

In this paper we discuss the design of a portable, low-cost focusing system based on compact dielectric lenses and its suitability for the use in a wide band 94 GHz FMCW Radar for civil safety applications. A Vivaldi antenna transmits the Radar signal directly into a dielectric cone in order to control the aperture angle. By using an additional lens system, the signal can be focused at targets in the range of several meters. Dielectric properties and dispersion of different materials have been investigated at W-band frequencies to optimize the lenses within the systems based on quasi-optical ray tracing models.