New random walk reduction algorithm in ring laser gyroscopes

The main factors which reduce the performance of ring laser gyroscopes (RLGs) are lock-ins and bias errors. A lock-in is a nonlinear effect that makes the output of the RLG unmeasurable due to a coupling with the backscattered light from the mirror when the input rotation rate is low. To prevent the lock-in effect, random dithering has been applied. However, a random walk due to the random dithering can result in a degraded RLG performance. Thus, a lower value for random walks is preferable. This is done by reducing the alignment time of the Laser Inertial Navigation System (LINS). In this paper, we propose a new algorithm that is used to estimate the phase errors due to lock-ins and so compensates for a random walk using the electric output of the RLG. To verify the performance of the proposed algorithm, a simulation was performed using RLG equations. The simulation results show that the proposed algorithm significantly reduces random walks and brings robustness to the timer clock frequency, which can lead to an easier implementation of hardware and algorithms