NONLINEAR DISTORTION COMPENSATION CIRCUIT AND NONLINEAR DISTORTION COMPENSATION POWER AMPLIFIER

摘要

PROBLEM TO BE SOLVED: To solve problems of a convertional nonlinear distortion compensation circuit that has had difficulties in realizing a small change in the characteristic because of bias fluctuation and dispersion in components in a highly accurate reverse characteristic in a power amplifier in the case of adopting a simple circuit configuration. SOLUTION: A diode 24 connected in parallel with a main line is connected to ground via a 2nd resistor 25 and a bias is applied from a power terminal 23 to the diode 24 via a 1st resistor 21. When an input level is increased, the diode 24 clips the input waveform and a rectified current flows through the diode 24. Thus, a bias point of the diode 24 is changed to increase an equivalent resistance thereby obtaining a characteristic where the gain is increased with respect to an increase in the input level and the phase is delayed. In this case, the stable characteristic can be realized against bias fluctuation by selecting a sufficiently high resistance for the 1st resistor 21 and the reverse characteristic of the power amplifier can be realized by adjusting the resistance of the 2nd resistor 25.