Design of ring laser gyroscope SINS data acquisition circuit

The measurements of dither offset frequency is used to reduce the impact of latching error for laser gyro. The method of linear phase low-pass filter is used to eliminate the dither impact and high-frequency measurement noise. Distributed arithmetic algorithm is used for the FIR filter, distributed arithmetic algorithm can complete a number of multiply operations efficiently by converting the multiply operation into the look-up table structure. The main functional circuits such as counters, digital signal processing algorithms are completed in FPGA, data acquisition circuit is designed with FPGA. PC/104 system is used as control module, whose driver is under DOS system. The data displays by interrupt. The experiments show that this acquisition card counts real-time and precise numbers. Taking PC/104 system simplifies the device complicacy.