Adaptive Filtering Algorithm Improvement And The Application In The Shortwave Signal Processing

The Adaptive filtering algorithm for adaptive signal processing in today's most active research topics. In recent years, wireless communication technology on a global scale demonstrated strong vitality and huge market potential. With the rapid development of wireless communication technology, communication rate is continuously improving. However, high-speed communication on the wireless channel, signal transmission due to multipath effect, the limited channel bandwidth and channel characteristics of the imperfections will inevitably lead to inter-symbol interference, which will get the quality of communicate serious affected.In order to overcome inter-symbol interference caused by signal distortion, usually used the balance filtering technique to offset in the communication system receiver. In the next-generation wireless communication systems, such as short-wave communication, data transmission and the fast time-varying of the actual channel requires adaptive equalization filter must be able to track changes in channel parameters to correct weights constantly in order to achieve the elimination of inter-symbol interference. This makes the search for fast convergence, low computational complexity, good numerical stability of the adaptive equalization filter algorithm has very important significance.This paper summarizes background and significance of the subject, describes the situation at home and abroad of adaptive filtering technique and the basic principles of adaptive filters. Then analyzed a variety of adaptive filter algorithm, the comparison of algorithms and adaptive filter applications. Then based on the basis of existing algorithms present a new variable step adaptive filter algorithm and the algorithm in some functional improvements and adaptive equalization filtering algorithms in the classic and new algorithms for the performance by MATLAB simulation and comparison. Simulation results show that the improved algorithm converges faster and get stable better than the original algorithm.Finally, the proposed algorithm is applied to improve signal processing in the short-wave communication systems, in computer simulations, we choose pseudo-random binary sequence as a reference signal and the classic Watterson Channel as HF channel model, the new algorithm and the classical algorithm simulation in the short-wave communication system environment is mainly based on Matlab's Simulink components, but also have some simulation using Matlab m-code directly completion Matlab simulation also uses the powerful graphics capabilities of the visual description. Matlab simulation also uses the powerful graphics capabilities of the visual description of the results. Through the classical method and new algorithm in communication system simulation results to illustrate the improved convergence speed and more stable after convergence, use the improved algorithm and LMS algorithm alone in improved results and confirm the effectiveness of the new algorithm, we can see the using the new algorithm can significantly reduce and eliminate the impact of multipath and can greatly improve the balance of filtering performance.