A method for compensating for a relative time delay between in-phase and quadrature signal paths of a communications system utilizing an analog quadrature modulator, comprising: receiving digital in-phase and quadrature forward path signals from a forward path input; time adjusting the in-phase and quadrature forward path signals using in-phase and quadrature interpolation circuits employing interpolating coefficients coupled to the forward path input; digitally computing the timing errors for the in-phase and quadrature signal paths from a forward path signal and an observation signal, said observation signal corresponding to an output of the communications system, the method being characterized in comprising: calculating said interpolation coefficients from said in-phase and quadrature timing errors; computing the timing error for the in-phase signal path from the difference between the cross-correlation of the in-phase forward path signal with a delayed in-phase part of the observation signal and the cross-correlation of the in-phase forward path signal with an advanced in-phase part of the observation signal; computing the timing error for the quadrature signal path from the difference between the cross-correlation of the quadrature part of the forward path signal with a delayed quadrature part of the observation signal and the cross-correlation of the quadrature part of the forward path signal with an advanced quadrature part of the observation signal; and adjusting one or both of the in-phase and quadrature signal paths to remove the relative time delay between the in-phase and quadrature signal paths. receiving digital in-phase and quadrature forward path signals from a forward path input; time adjusting the in-phase and quadrature forward path signals using in-phase and quadrature interpolation circuits employing interpolating coefficients coupled to the forward path input; digitally computing the timing errors for the in-phase and quadrature signal paths from a forward path signal and an observation signal, said observation signal corresponding to an output of the communications system, the method being characterized in comprising: calculating said interpolation coefficients from said in-phase and quadrature timing errors; computing the timing error for the in-phase signal path from the difference between the cross-correlation of the in-phase forward path signal with a delayed in-phase part of the observation signal and the cross-correlation of the in-phase forward path signal with an advanced in-phase part of the observation signal; computing the timing error for the quadrature signal path from the difference between the cross-correlation of the quadrature part of the forward path signal with a delayed quadrature part of the observation signal and the cross-correlation of the quadrature part of the forward path signal with an advanced quadrature part of the observation signal; and adjusting one or both of the in-phase and quadrature signal paths to remove the relative time delay between the in-phase and quadrature signal paths. calculating said interpolation coefficients from said in-phase and quadrature timing errors; computing the timing error for the in-phase signal path from the difference between the cross-correlation of the in-phase forward path signal with a delayed in-phase part of the observation signal and the cross-correlation of the in-phase forward path signal with an advanced in-phase part of the observation signal; computing the timing error for the quadrature signal path from the difference between the cross-correlation of the quadrature part of the forward path signal with a delayed quadrature part of the observation signal and the cross-correlation of the quadrature part of the forward path signal with an advanced quadrature part of the observation signal; and adjusting one or both of the in-phase and quadrature signal paths to remove the relative time delay between the in-phase and quadrature signal paths.