RF Power Analysis on 5.8 GHz Low-Power Amplifier Using Resonant Tunneling Diodes

This letter reports the analysis of RF power characteristics in a microwave amplifier using resonant tunneling diodes (RTDs). The implemented IC shows a return loss of more than 11 dB with a low dc-power consumption of 0.42 mW and a power gain of 8.6 dB at 5.8 GHz. The maximum linear RF output power with a uniform gain of 8.6 dB is measured to be -25.4 dBm at the same frequency. The gain hump phenomenon is observed in an input power range from -32 dBm to -16 dBm, and is shown to arise from a sudden movement of the operating point from the negative differential resistance (NDR) region to the positive differential resistance (PDR) region, based on a large-signal load-line analysis together with a harmonic balance simulation.