System for digital cancellation of clock jitter induced noise in a gyroscope with provides better power effect

Abstract

In a digital gyroscope, the rate signal (including the quadrature) and the displacement signal of the drive part are sampled with an ADC. This displacement signal has the same frequency and phase as the quadrature signal that gets sampled in the rate channels. The displacement signal is sampled with the same clock as the rate signal resulting in the displacement signal having the same close-in phase noise folded into the signal band as the sampled quadrature in the rate signal. The sampled drive signal is subtracted from the sampled rate signal to eliminate the clock jitter induced noise in the rate signal. This relaxes the close-in phase noise requirement of the PLL and allows for a low power PLL implementation.