A compact power amplifier based on a 5 W GaN HEMT in S-band application

In this paper, the design of an S-band power amplifier (PA) with a high output power based on a GaN HEMT has been demonstrated. The proposed PA is composed of a packaged GaN device, an input / output radio frequency (RF) signal matching network, as well as a DC bias network. The optimal output load is optimized after a trade-off between achieving a high output power and a high power added efficiency (PAE). As the transistor is not unconditionally stable, stabilization has been taken into account in the DC bias network design in such a way that the RF performance is minimally affected. Finally, the layout is finely tuned in order to optimize the interconnection parasitics and to minimize the performance degradation. Characterized with a standard measurement setup with two SMA connectors, the measured result shows that the proposed PA achieves a power gain of 11 dB with an output power of around 35 dBm.