A 90W S-band high power amplifier for broadband wireless applications

This paper describes a successfully developed 90W high power amplifier with the wide band range in S-band. The power amplifier consists of two 50W GaAs FET chips and small 180 degrees coupler transmission line circuit that was developed in an external matching network. The wide band performance was achieved by the 180 degrees coupler transmission line circuit and the multi-stage internal circuit. The power amplifier delivered an output power of 90W in the frequency range of 2.9 to 3.3 GHz. To our knowledge, this is the highest power and frequency range ever reported in S-band. A low 3rd-order intermodulation distortion (IM3) of less than -30 dBc was also achieved at a 10 dB back-off point from saturation power in the frequency range of 2.9 to 3.4 GHz. The developed power amplifier is suitable for the base station in broadband wireless access in the S-band.