Double closed-loop hybrid fiber gyroscope using digital phase ramp

Abstract

It is now well-established that the use of a reciprocal configuration (1) gives a very good bias stability (2, 3, 4) to fiber gyroscopes. It has been shown that a double Y junction has a lack of spatial rejection which limits the performances of the system (5). Furthermore the usual biaising phase modulation technique (1) gives a rate signal with a sine response. Closed-loop signal processing techniques which linearize and stabilize the scale factor are a very important subject of concern.