Design and Performance of a 600-W -Band Amplifier Using Spatially Combined GaAs FETs for Satellite Communications Ha Trong Than, George W. Sun, Geovanni S. Cuellar

Abstract

This paper describes the design and performance of a -band ampli fier with over 600 W of saturated output power . This amplifier is intended for use in commercial broadcast satellite uplink base stations. The ampli fier uses spatial power combining to combine the output powers of sixteen internally matched 45-W GaAs FETs. The ampli fier also comprises pre-ampli fication and driver amplification stages, a level control variable attenuator, and a predistortion linearizer. The unit also includes a power supply as well as a user monitor and control interface. We will present various measures of this amplifier’s linearity performance, demon- strating its suitability for use in broadcast applications. Finally, we will present results from power combining two of these ampli fiers, resulting in a solid-state amplifier with 1.4 kW of saturated -band output power.