Design And Implementation Of North-Seeking System Based On Dual DSP

The north-seeker is one kind of inertial instruments. By gyro and accelerator, it measures the angular speed of Earth rotation and the acceleration of gravity, and then the angle between the reference axis of carrier and the real north is resolved through computations. After that, rotating the sensitive axis of the gyro to point the real north, the instrument is working in the azimuth mode to constantly display azimuth angle of the carrier. In this paper, the north-seeking theory is introduced in detail, and a whole scheme on north-seeking system is presented. At the same time, the theory of azimuth instrument is discussed.Digital Signal Processing is a newly technology in modern digital signal processing. The occurrence of DSPs makes the construction of sampling data system more clearly, the procedure simpler and the function stronger.Two different DSPs (TMS320LF2407 and TMS320VC5402) of Texas Instruments Company are used in this north-seeking system.TMS320LF2407 is for control and TMS320VC5402 is for realization of north-seeking arithmetic, which does fully exert the advantages of these two different DSPs. Thus, both the precision and speed are improved. In this paper, both hardware and software of this north-seeking system based on dual DSP are introduced in detail.In the real environment, signals are always mixed with noises. In this paper, analog filter is introduced in hardware design, and FIR filter (digital filtering technique) is designed in software design after A/D conversion for a second filtering. Thus, north-seeking precision is greatly improved.