A 20ghz Switched Beam Lens Antenna For Airborne Communications Applications

A 20GHz switched beam lens antenna is presented for airborne communications applications. A 14-element prototype with 6 '' lens has been tested to demonstrate the concept. A 37-element array designed with a 2 '' lens has been analyzed and is currently under development. The system consists of: a ferrite circulator switch network implemented in waveguide for low loss switching; an array of polarizers used to provide circular polarization; a feed network designed for optimum lens feed layout and switch layout; and a 2 '' diameter spherical lens. The gain is expected to be 18dBi +/- 1dB over the 37 elements with an axial ratio of < 3dB across the 37 elements and a field of regard of 120 degrees.