Patent ID: 7155132

Claim:
A transmitter, comprising: an input, coupleable to receive an RF signal; a pre-distorter, coupled to the input, that selectively adds distortion to the RF signal; a laser that provides a light source for optical transmission; a modulator, coupled to the laser and the pre-distorter, that modulates the light from the laser with the RF signal from the pre-distorter to produce an output for the transmitter; wherein the distortion added by the pre-distorter is controlled to reduce distortions in the output of the transmitter generated by the modulator; a distortion monitor, coupled to the output of the transmitter, that monitors at least one frequency of the output of the transmitter to detect distortion in the modulator output without the use of a pilot tone; and a microprocessor, coupled to the distortion monitor, the pre-distorter, and the modulator that uses an output of the distortion monitor to selectively generate control signals for the modulator and the pre-distorter to reduce the distortion in the output of the transmitter.