A quasi-optical receiver with angle diversity

A quasi-optical receiver front end consisting of a 10-GHz lens amplifier antenna array and three self-oscillating grid mixers is presented. The lens amplifies incoming plane waves incident from different directions and focuses them to three points where the mixers are placed. Because of the angle-preserving nature of the amplifier, the mixers generate independent IF signals from three incident directions. The resulting angle diversity is useful for reducing multipath fading in communications.