A 30.8-dBm SiGe Ka-Band Power Amplifier Using Resonated Amplifier Cores

This article presents a novel design method for power amplifiers (PAs). The method enables the systematic design of efficient PA cores with large device parallelization by resonating out parasitic capacitances inside the core. The method is compared with direct device parallelization and improves available output power and power-added efficiency (PAE) for large PA cores. A PAE advantage of 6%–8% for a fixed saturated output power of 30 dBm is predicted at 28 GHz. To demonstrate the capability of the method, a high-power Ka-band PA in 130-nm silicon germanium (SiGe) BiCMOS using resonated amplifier cores is designed. At 28 GHz, the PA achieves a saturated output power of 30.8 dBm at a maximum PAE of 25.5%. For a 200-MSym/s 64-QAM signal, an average output power of 22.8 dBm at an average PAE of 7.1% is demonstrated.