Rectangularly driven class-A harmonic-control amplifier

A rectangularly driven class-A harmonic-control amplifier (rHCA) is studied, which combines the advantage of high device drain efficiency (/spl eta//sub D/) of a switched-type amplifier with the advantage of high gain (G) of class-A operation, thus maximizing its power-added efficiency (PAE). In this rHCA, harmonics are controlled such that drain-to-source voltage becomes half-sinusoidal. This reduces the necessary supply voltage without degrading output power. In comparison with a class-F amplifier using the same transistor, the realization of such an rHCA has demonstrated 0.4-dB larger output power, 3.8-dB increased gain, 4% higher PAE, and 22% lower drain supply voltage at 1.62 GHz.