Patent ID: 7646239
Filing Date: 2010-01-12
Classification: H03F

Abstract:
1. A feed-forward amplifier including a main amplifier, a predistortion compensator provided in an input path of the main amplifier, distortion detection means for detecting a distortion component of the main amplifier, and distortion removal means for inserting the distortion component detected from the output of the main amplifier to remove distortion, the feed-forward amplifier comprising: a first variable attenuator and a first variable phase-shifter provided in an input path of the predistortion compensator; a second variable attenuator provided between the predistortion compensator and the main amplifier; first temperature detection means for detecting temperature in the neighborhood of the main amplifier; first control means for controlling the first variable attenuator and the first variable phase-shifter to minimize an input signal component contained in the distortion detected by the distortion detection means; and second control means for controlling the second variable attenuator so that the predistortion compensator minimizes the distortion of the main amplifier according to the temperature detected by the first temperature detection means.