Reducing a gyroscope-bias component in a determined value of angular velocity with simultaneous sensor operation

A calibration angular velocity is generated about a sense axis, and a gyroscope assembly generates a signal in response to that angular velocity and a second angular velocity which may be unknown. A bias component of the second angular velocity is reduced in response to the gyroscope signal. The gyroscope may be a vibrational gyroscope which is made to rotate with the calibration angular velocity. The signal may be demodulated into quadrature-phase and in-phase signals. The calibration angular velocity may have a large frequency compared to the second angular velocity. The presence of a component of the calibration signal in the quadrature-phase signal, and hence the presence of a bias component in the in-phase signal, may then be detected and then suppressed using a phase adjuster. The in-phase signal may then be processed using a low-pass filter to suppress the high-frequency calibration angular velocity to determine the angular velocity.