A 15-20 GHz Watt-level GaAs Power Amplifier Module Using Single-bias Technique

This paper presents a single-bias method for a depletion-mode GaAs power amplifier (PA) module. The module utilizes a four-stage GaAs pseudomorphic high electron mobility transistor (pHEMT) monolithic microwave integrated circuit (MMIC). With the proposed single-bias method, the PA module achieves a 3-dB bandwidth ranging from 14 to 19 GHz, a maximum small-signal gain of 25 dB at 16.5 GHz, a saturated output power of 30 dBm, and a peak power added efficiency (PAE) of 11.8%. Incorporating the digital predistortion enables the module to reach an output power of up to 30 dBm. The measured error vector magnitude remains within 2% for the 64QAM modulation scheme. The superior performance of the proposed PA module, employing the single-bias method, makes it well-suited for satellite communications or point-to-multipoint radios.