Patent ID: 7415252
Filing Date: 2008-08-19
Classification: H03F,H04L

Abstract:
1. A system for forming a predistorted signal from a broadband interpolated baseband signal for a transmit power amplifier having n cascaded branches, comprising: a predistortion unit provided for the first branch of the amplifier, the predistortion unit producing an estimated output signal of the transmit power amplifier, the estimated output signal being formed based on memory effects of the amplifier, the predistortion unit having an input receiving the interpolated baseband signal as an interim predistorted signal; first and second adders, a distortion unit, a predistortion unit, and a digital filter provided for every jth branch of the amplifier where 2≦j≦n, wherein: a downstream filer connected to the output of the second adder of the nth branch, the downstream filter producing the predistorted signal.