Research on the signal synchronization technology of three axes FOGs

For the strapdown inertial navigation system, whether the output signal of 3-axes fiber optic gyroscopes (FOG) is synchronized or not, impacts the performance of system seriously. This paper gave a novel way to make the gyros´ signal synchronized without any change of hardware. Firstly, the all-digital closed-loop signal processing of single FOG was analyzed deeply, especially the part of digital signal conversion and output. Then, a method of timing control base on FPGA was realized. Finally, the navigating experiment of strapdown system on the simulation and laboratory conditions were implemented. The simulation results showed that the performance of navigation was improved obviously after the signal synchronization of gyros. The method can be used to realize the signal synchronization of all accelerometers and gyros in strapdown system.