Patent ID: 7349490
Filing Date: 2008-03-25
Classification: H03F,H04L

Abstract:
1. A digital predistortion circuit, comprising: an input for receiving a digital input signal in rectangular coordinates having an in-phase component and a quadrature component; a first signal path coupled to the input and including in phase and quadrature predistortion correction addition circuits, said first signal path providing the input signal to the predistortion correction addition circuits in rectangular coordinates; and a second signal path, coupled in parallel to said first signal path and coupled to the input and to the predistortion correction addition circuits, the second signal path including a rectangular to polar coordinate conversion circuit converting the in phase and quadrature input signal to magnitude and phase components, and a predistortion correction circuit having an input receiving the magnitude of the input signal and outputting a predistortion correction signal; wherein the second signal path provides in phase and quadrature predistortion correction values corresponding to the predistortion correction signal to the predistortion correction addition circuits in the first signal path and the predistortion correction addition circuits add the correction values to the input signal and output predistorted in phase and quadrature signals.