A non-uniform GaN power TWA for 2 to 10 GHz suitable for square-wave operation

Abstract

A broadband GaN monolithic power amplifier covering the 2 to 10 GHz band is presented. It is based on a nonuniform traveling-wave architecture using 4 transistor cells with 4x125 µ µ µ µm gate width each. The amplifier achieves 7 to 11 dB small signal gain in the frequency band between 2 and 10 GHz. The circuit delivers between 2.5 and 4.5 W over the bandwidth from 2 GHz up to 10 GHz. At maximum output power a PAE higher than 20% is achieved. In addition, large signal operation with square wave signals have been demonstrated at 1 and 2 Gbps, with 5 W output power at 1 Gbps.

A 39.7 dBm and 18.5% PAE compact X to Ku band GaN Travelling Wave Amplifier

“…If these conditions are met then the amplifier is optimized in terms of small-signal gain and gain flatness as in [5]. However, as described in [6] when trying to optimize the TWA in terms of output power and PAE, nonuniform topologies should be concerned. This approach consists in increasing transistor sizes in cells close to the output and changing size of transmission lines in order for each cell to see its optimal impedance in terms of output power and PAE.…”