Patent ID: 9008221
Filing Date: 2015-04-14
Classification: G06F,H04B,H04L

Abstract:
1. A spurious frequency attenuation servo, comprising: a first function generator that generates a first signal at a first frequency, the first signal including at least one spur at at least one respective spurious frequency; a second function generator that generates a second signal in-phase with the first signal and at a spurious frequency; a third function generator that generates a third signal ninety degrees out-of-phase with the first signal and at the spurious frequency; an in-phase mixer configured to input the second signal and a feedback signal; a quadrature-phase mixer configured to input the third signal and the feedback signal; an in-phase error accumulator configured to input the signal from the in-phase mixer; a quadrature-phase error accumulator configured to input the signal from the quadrature-phase mixer; an in-phase multiplier to multiply an output from the in-phase error accumulator with the second signal; a quadrature-phase multiplier to multiply an output from the quadrature-phase error accumulator with the third signal; and at least one summing node to sum the first signal, an output from the in-phase multiplier, and an output from the quadrature-phase multiplier to form an output signal that is fed back to the in-phase mixer and the quadrature-phase mixer, wherein the at least one spurious frequency of the first signal is canceled from the first signal output from the summer.