Enhancing the Output Power and Efficiency for a Set Noise-Power Ratio of a K-Band Power Amplifier By Means of Analog Pre-Distortion

This paper investigates the output power and efficiency improvements in a K-band power amplifier (PA) that can be achieved using analog pre-distortion (APD). At first, the APD tuning voltage is optimized to maximize gain and phase flatness using Gaussian pulses. Next, the PA average output power is swept and the noise-power ratio (NPR) of a 750 MHz signal is measured with APD enabled and disabled. It is found that APD improves the PA average output power between 1 W and 1.6 W (or +2 dB) for NPRs between 16 and 29 dB. At the same time, APD improves PA efficiency by 1 to 7 percentage points (pp) for this 31 % peak-efficiency PA. These results suggest the use of APD for improving PA efficiency and output power.