Patent ID: 7474708

Claim:
A modulator for a multimode transmitter comprising: a) polar modulation circuitry adapted to: i) convert a quadrature input signal into amplitude and phase components; and ii) predistort the amplitude component and the phase component to provide predistorted amplitude and phase components; b) phase-to-quadrature conversion circuitry adapted to convert the predistorted phase component into a quadrature phase signal; c) combiner circuitry adapted to combine the quadrature phase signal and the predistorted amplitude component to provide a quadrature transmit signal for a first mode of operation; and d) further modulation circuitry adapted to: i) modulate the quadrature transmit signal when operating in the first mode of operation to provide a modulated signal at a desired radio frequency for the first mode of operation; and ii) modulate either the predistorted phase component or the quadrature phase signal when operating in a second mode of operation to provide a constant envelope phase modulated signal at a desired radio frequency for the second mode of operation.