A two-stage spatial amplifier with hard horn feeds

A spatial amplifier consisting of two stages, With each stage employing nine HEMT´s, has been developed. The coupling to and out of the spatial amplifier is accomplished by placing it in the reactive field of two hard horn antennas. The hard horns´ improved aperture field uniformity ensures the simultaneous saturation of most of the active devices across the amplifier array. The amplifier has a small signal gain of 16.2 dB at 9.98 GHz and produces 90 mW at a 2-dB compression point.