Design of a CMOS Distributed Power Amplifier with Gradual Changed Gain Cells

A non-uniform Distributed power amplifier (DPA) is designed and implemented in a 0.18 μm CMOS technology. The gradual changed gain cells work with the tapered on-chip inductors to construct non-uniform artificial transmission lines, which improves the output power and efficiency in a wide frequency band while maintaining good input and output impedance matching. The proposed DPA achieves 9dB average associated gain from 1 to 17.2GHz, and the input return loss is less than -9dB while the output return loss is less than -8.5dB in the desired frequency band. The output power at 1dB Output compression point (OP1dB) is more than 7.8dBm in the frequency band of 2-16GHz, and the peak power-added efficiency is 6.2% with the OP1dB 12.6dBm at 4GHz.