Research Of SINS Algorithm In Frequency Domain

With the development of technology, more and more people are familiar with the navigation. The inertial navigation system is the autonomous navigation system,which is with a fully independent performance, and it does not rely on outside information, so it is good for hiding and it is free from any interference with natural conditions or the environment.Also, it can work for a long time, and its accuracy is good. Therefore, it becomes a widely used method of the aerospace, aviation, and marine areas.The strapdown inertial navigation system, which uses "Mathematics platform" instead of the physical platform, reducing system cost, easy to install and maintain, has been widely used in the field of low accuracy. The algorithm of SINS is the key of the accuracy of navigation system. The development of digital processing technology and the needs of the people on the navigation system, make the re-development of SINS algorithm in the transform domain is very important. This paper studies the correlation algorithm of SINS based on the signal processing technology in the transform domain.The accuracy of strapdown inertial navigation system depends on the inertial navigation components and algorithms. Gyro signal denoising and navigation algorithm is mainly studied in this paper.The method of improving low accuracy gyro depended mainly on the error mathematical model of gyro, reducing the impact of gyro drift through the digital filter. The FIR filter is used for gyro denoising in this paper. Wavelet analysis, with its good performance in time-frequency domain, has achieved great success in signal analysis. In this paper, the wavelet threshold denoising method in the gyro signal denoising has been studied. Lifting scheme wavelet transform method to Gyro Signal filter was used, and has achieved good results.In the algorithm domain of strapdown inertial navigation, the common coordinate system and the basic working principle of inertial navigation are introduced firstly. Then, the calculation method on attitude, position and velocity of inertial system is analyzed and simulated. In order to compensate the drawback of conventional navigation algorithms using of numerical integration, firstly, we analyzes the continuous signal reconstruction in frequency, the source of the signal reconstruction error, provides a way of reducing the reconstruction error, and the formula of signal reconstruction in frequency is obtained, then strapdown navigation algorithm in frequency domain is given and simulated in the MATLAB environment. The simulation results show that the frequency domain strapdown navigation algorithm can effectively improve inertial navigation system accuracy.