Adaptively self-correcting modulation system and method

An adaptively precompensated quadrature modulation method for accurately forming a modulated signal, comprising the steps of:

• (a) applying a set of correction factors to uncorrected in-phase and quadrature modulation waveform samples to produce corrected in-phase and quadrature modulation samples;
• (b) forming a corrected in-phase modulation waveform from the corrected in-phase modulation samples and modulating a substantially cosinusoidal carrier wave with the corrected in-phase modulation waveform, forming a corrected quadrature modulation waveform from the corrected quadrature modulation samples and modulating a substantially sinusoidal carrier wave with the corrected quadrature modulation waveform, and forming a modulated output signal by summing the modulated cosinusoidal and sinusoidal carrier waves;
• (c) forming a modulated transmitted signal by upconverting and amplifying the modulated output signal to a selected desired transmission frequency and power level;
• (d) collecting digital samples of the modulated transmitted signal;
• and
• (e) determining the set of correction factors from said digital samples and the uncorrected samples.

An adaptively precompensated quadrature modulator for accurately forming a modulated signal, comprising:

• a first processor that applies correction factors to uncorrected samples of an in-phase modulation waveform and a quadrature modulation waveform, thereby generating corrected samples, and that converts the corrected samples into a corrected in-phase modulation waveform and a corrected quadrature modulation waveform;
• a quadrature modulator that impresses the corrected in-phase modulation waveform on a substantially cosinusoidal carrier wave and that impresses the corrected quadrature modulation waveform on a substantially sinusoidal carrier wave, thereby producing the modulated signal;
• a modulation assessment receiver, coupled to the quadrature modulator, that generates digitized samples of the modulated signal;
• and
• a second processor that is coupled to the first processor and the modulation assessment receiver, that determines the correction factors based on the digitized samples and the uncorrected samples, and that communicates the correction factors to the first processor.