Shock-tolerant multioscillator ring laser gyro

Apparatus for processing signals with frequencies fL and fR from a multioscillator ring laser gyro at regular time intervals, the difference fΔθ, of fL and fR being the angular rotation measure of the ring laser gyro, the sum fF of fL and fR divided by 2 being the Faraday bias frequency, fLP, fRP, fFP, and fΔθP being the values of fL, fR, fF, and fΔθ for the present time interval, the apparatus comprising:

• a preprocessor for determining two or more of the values MLP, MRP, MFP, and MΔθP of a set of functions ML(fL), MR(fR), MF(fF), and MΔθ(fΔθ), ML(fL), MR(fR), MF(fF), and MΔθ(fΔθ) being functions respectively of fL, fR, fF, and fΔθ;
• a first processor for storing two or more processed values MLS, MRS, MFS, and MΔθS of the functions ML(fL), MR(fR), MF(fF), and MΔθ(fΔθ) if the corresponding values of MLP, MRP, MFP, and MΔθP are valid, a processed value being derived from the value for the present time interval and zero or more processed values for prior time intervals.
• a second processor for determining fΔθP or a function thereof from zero or more valid function values obtained as a result of executing step (a) during the current time interval, zero or more processed values obtained as a result of executing step (b) during a prior time interval, and zero or more extrapolated values obtained by extrapolating the processed values obtained as a result of executing step (b) during a prior time interval to the present time interval.