Application of TD filter in DTG north seeking system

In this paper, the applicability and advantage of tracking differentiator (TD) filter in dynamically tuned gyro (DTG) north seeking system is presented. According to the working principle of north seeking system, the system structure is first designed based on DSP. Then TD filter with discrete form, which is easily realized in DSP, is adopted to eliminate both the noise and disturbance in the output signal of gyro. Practical measurement data are given to show that the north-seeking accuracy is improved effectively, and the seeking time is shortened by TD filter.