As wireless communications technology and the continuous development of increasingly mature, how in the complex environment of effective communication signal demodulator and is conducive to achieving figures in recent years on a new topic. In the field of communications, adaptive algorithm in the adaptive equalization, adaptive frequency tracking and detection, such as the application of more mature. With the in-depth study and found that the use of adaptive filter performance and anti-jamming signals on the tracking capability, could be more simple with the extraction of information, a coherent demodulation more common than ideal performance. Through the adaptive algorithm for a variety of research and analysis and use of various algorithms Matlab a simulation.In this paper, include the following elements: Discussed the basic minimum square algorithm performance and step factor on the performance of algorithm. The adaptive filter is widely used nowadays．Based on the LMS adaptive algorithm，the performance of adaptive filter is determined by its order and self-adaptive step size，which influence the convergence rate，calculation complexity and steady state error of the system．This paper analyzes the principle of LMS adaptive filter，studies the two parameters efect on the filtering perform ance separatelyLMS adaptive filter in the system identification, since the reunification process of adaptive predictor, noise cancellation, echo cancellation and the DS system to achieve the application of pseudo-synchronous code, using a Matlab programming simulation and analysis.
