Class-A GaAs FET power amplifier design for optimizing intermodulation product

The intermodulation products of a Class-A GaAs FET amplifier were estimated using harmonic balance techniques. Output back-off and power-added efficiency at any specified D/U ratio are determined under various matching conditions using FETs with different cutoff frequencies. For optimum design of the amplifier, charts are given which show back-off and efficiency at the specified D/U ratio as functions of small-signal gain and ratio of operating frequency to cutoff frequency. >