Patent ID: 6144706
Filing Date: 2000-11-07
Classification: H03F,H04B

Abstract:
A distortion compensation circuit connected between an unbalanced input terminal to which a high frequency signal is inputted and an unbalanced output terminal to which an object subjected to secondary distortion component compensation is connected, the distortion compensation circuit comprising:a fundamental wave passing path for passing a fundamental wave therethrough; anda distortion addition path for adding distortion, the distortion addition path being parallel to the fundamental wave passing path,wherein the fundamental wave passing path comprises an attenuation component circuit for signal attenuation formed by at least one resistor, and a delay line connected in series with the attenuation component circuit for coinciding arrival times at the unbalanced output terminal of a signal passing through the distortion addition path and a fundamental wave passing through the fundamental wave passing path,wherein the distortion addition path comprises a first attenuation circuit for signal attenuation comprising a resistor and first and second diodes for generating secondary distortion connected in series between the unbalanced input terminal and ground, and a second attenuation element for setting a signal level comprising a resistor connected in series between the unbalanced output terminal and a connection point between the first diode and the second diode, andwherein the first and second diodes are connected to the connection point at their electrodes of same polarity, and magnitudes of DC bias currents supplied to the first and second diodes are set in a manner that, when the high frequency signal applied to the unbalanced input terminal reaches the connection point and is subjected to amplitude expansion and compression alternately in every half period of the high frequency signal, a voltage value expanded from the high frequency signal is equal to a voltage value compressed therefrom.