Image rejection calibration includes initializing the calibration mode by applying to quadrature mixers, in place of the wanted RF input, an RF source in the frequency range of the wanted RF input, sensing the power output from the poly-phase filter, developing gain adjust and phase adjust correction values in response to the power output and adjusting in accordance with the correction values the gain of the quadrature signals from the quadrature mixers to the poly-phase filter and the phase of local oscillator quadrature signals from the local oscillator to the quadrature mixers to reduce the power output.