A scanning reflector using an off-axis space-fed phased-array feed

An architecture for a scanning reflector antenna that supports wide-angle scanning, multioctave tunable bandwidths, transmit and receive operation, and monopulse processing is presented. It consists of a parabolic dish with an offset phased array. The array is actually a feed-through lens fed from a small feed array in the back of the lens. Beam steering is accomplished by using the feed array to illuminate clusters of elements within the lens that correspond to far-field beam positions. The evolution of the architecture and a computer model is described. Simulated and measured performance results are reported. Off-axis scanning of 10° to 15° appears to be possible while still supporting gain magnifications of four to five