Patent ID: 7760833

Claim:
A quadrature demodulator comprising: a first phase rotator to generate first and second weighted signals by weighting an input signal by a first scalar and a second scalar in response to a phase select signal; a second phase rotator to generate third and fourth weighted signals by weighting the input signal by a third scalar and a fourth scalar in response to the phase select signal; first and second mixers to generate first and second component signals by mixing the first and second weighted signals with an in-phase signal; and third and fourth mixers to generate third and fourth component signals by mixing the third and fourth weighted signals with a quadrature signal; where each phase rotator comprises a set of transconductance cells arranged to weight the input signal in response to the phase select signal; and where: the phase select signal comprises individual select signals; the transconductance cells have different gains to provide different weights; and the transconductance cells are arranged to be selectively enabled in response to the individual select signals.