An Optimized 5G Driver Amplifier for 3.5 GHz Band with 51.37% Efficiency

This paper presents a driver amplifier designed for 5G applications, specifically targeting the 3.5 GHz frequency band allocated for India. The amplifier design employs the load-pull technique to optimize efficiency, while improved impedance matching has been achieved using a two-stub matching network. The performance of the amplifier has been validated through power amplifier (PA) measurements, focusing on gain, efficiency, and delivered power. The developed PA achieves a small signal gain of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$13.5 \pm 0.5 ~\text{dB}$</tex> across the entire operating band and provides an output power of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$44.5 \pm 0.5 \text{dBm}$</tex> at saturation. It also maintains an efficiency of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$\mathbf{5 1. 3 7 \%}$</tex> at saturation throughout the operating band. Compared to the existing PA designs, the proposed design provides better small signal gain.