Patent ID: 7423958
Filing Date: 2008-09-09
Classification: H04L

Abstract:
1. A transmitter for sending signals over wireless channels, comprising: a modulator for modulating signals to be sent and for distributing modulated signals among a plurality of subcarriers; a predistorter for predistorting the signals distributed among the plurality of subcarriers; a signal generator for generating a test signal; a multiplier for multiplying the test signal by at least one of the distributed signals and the predistorted signals at predefined time intervals; a mixer for converting at least one of the multiplied signals and the predistorted signals from a baseband into an intermediate frequency; an amplifier for amplifying the converted signals; an antenna for sending a first portion of the amplified signals; a mixer for mixing a second portion of the amplified signals down from the intermediate frequency to the baseband; and a measuring module for comparing the mixed-down signals with the at least one of the multiplied signals and the predistorted signals to determine transfer properties of the amplifier and to notify the predistorter of the transfer properties of the amplifier, wherein the measuring module is configured to compare a test signal in the mixed-down signals with a test signal in the at least one of the multiplied signals and the predistorted signals to obtain the transfer properties of the amplifier, and wherein the predistorter is configured to predistort the signals distributed among the various subcarriers according to the transfer properties of the amplifier.