Patent ID: 6148185
Filing Date: 2000-11-14
Classification: H03F,H04B

Abstract:
A feed-forward amplifying device for a main signal system, comprising:a distortion extracting loop circuit including a main amplifier for amplifying a main signal in the main signal system, said distortion extracting loop circuit being operable to produce a distortion extracting signal by controlling the phase of said main signal by canceling a main signal component of an output from said main amplifier; anda distortion removing loop circuit disposed at the rear stage of said main amplifier for outputting only said main signal component of the main signal in the main signal system at the rear stage of said main amplifier using said distortion extracting signal produced by canceling said main signal component;said distortion extracting loop circuit being operable to execute a phase control at an optimum control point disposed within a range between a maximum phase control point where said main signal component can be canceled to a maximum, and a peak point where said main signal component can be input at a peak level, said optimum phase control point being located at a position toward said maximum phase control point and far from said peak point.