Patent ID: 7778345

Claim:
A communication system comprising: a modulator configured to mix a transmit-path signal based on a local oscillator (LO) signal; an amplifier configured to amplify the mixed transmit-path signal to generate an output signal for transmission; a demodulator configured to generate a receive-path signal based on the output signal and the LO signal; phase-shift control components configured to provide the output signal and the LO signal to the demodulator during a first time duration and to provide a phase-shifted version of one of the output signal and the LO signal to the demodulator during a second time duration, the demodulator being configured to generate a second receive-path signal based on the one of the phase-shifted output signal and the phase-shifted LO signal during the second time duration; and at least one predistortion circuit configured to adjust at least one of the transmit-path signal and the receive-path signal based on a difference in signal characteristics of the receive-path signal during the second time duration relative to the first time duration.