64 to 70 GHz microstrip non-foster circuit class-J GaAs pHEMT power amplifier

This paper proposes a 64 to 70 GHz microstrip non-Foster circuit Class-J GaAs pHEMT (gallium arsenide pseudo high electron mobility transistor) power amplifier. The power amplifier (PA) was designed based on WIN Semiconductor's P10-10 process GaAs pHEMT transistor biased with drain supply voltage of 2 V at quiescent drain-to-source current of 2mA. The microstrip non-Foster circuit (NFC) provides the negative capacitance required to cancel the transistor input parasitic capacitance thereby sustaining the 6 GHz wideband bandwidth of the PA. The NFC effective capacitance across the bandwidth ranges from -0.1 to -1.4 pF. The effective negative capacitance at center frequency of 67 GHz stood at -0.15 pF. The drain efficiency, power added efficiency (PAE), output power and transducer power gain of the PA from 64 to 70 GHz stood at 60.5 to 55.5%, 45.1 to 37% 13.5 to 12.6 dBm and 5.5 to 4.6 dB respectively. The PA has small signal gain of 7 to 5.3 dB from 64 to 70 GHz.