Patent ID: 7518445
Filing Date: 2009-04-14
Classification: H03C,H03F,H04L

Abstract:
1. A method for providing a linear envelope elimination and restoration transmitter, comprising: generating an input amplitude signal and an input phase signal, wherein the input amplitude signal and the input phase signal are orthogonal components of an input signal, and wherein the input amplitude signal and the input phase signal are generated on respective first and second signal paths; processing the input amplitude signal along the first signal path using an amplitude error signal to generate a predistorted amplitude signal; processing the input phase signal along the second signal path using a phase error signal to generate a predistorted phase signal; providing the predistorted amplitude signal along the first signal path and the predistorted phase signal along the second signal path to a power amplifier to generate an output signal; and applying a first logarithmic amplifier to the output signal of the power amplifier to obtain a log-detected output signal, and applying a second logarithmic amplifier to the predistorted amplitude signal to obtain a log-detected predistorted amplitude signal; and applying a first amplitude limiter to the output signal of the power amplifier to obtain an amplitude-limited output signal, and applying a second amplitude limiter to the predistorted phase signal to obtain an amplitude-limited predistorted phase signal, wherein the amplitude error signal is generated from a comparison of at least the log-detected output signal with the log-detected predistorted amplitude signal, and wherein the phase error signal is generated from a comparison of at least the amplitude-limited output signal with the amplitude-limited predistorted phase signal.