Based On The Adaptive Filter Sess System

For Spread Spectrum Communication has many features, such as strong anti-jamming ability, strong keeping secret ability, it has been widely used in the modern communication systems. Traditional Spread Spectrum Communication adopts Pseudo-Noise (PN) codes as spreading codes. However, PN sequence is fixed and periodic, which threatens the transmission security. Self-encoded Spread Spectrum (SESS) employs random spreading sequences that are extracted from the random information data, abandoning the fixed sequence. That improves the security performance of the conventional SESS system and enhances the performance of anti-jamming.In this thesis, we first present the basic theory of Spread Spectrum Communication. Then the principle of SESS system is introduced. The generation of the SESS spreading code and its characteristics are also analyzed. The spreading code is acquired from the transmission data source. As a result, the method to generate the spread codes is very important. And the method determines the practical application of SESS communication system. Based on the principles of DSSS and SESS, the mechanism of SESS employing the AR filter is illuminated. It transfers the data source to dynamic Gauss White Noise. Then quantizing and optimizing the noise, we can get the final spread sequence.The characteristics of the spreading codes are one of the key factors which affect the performance of Spread Spectrum Communication. In SESS, the special way producing the spreading codes determines that the spreading codes are more important in SESS communication system. In chapter 6, the characteristics qualities relative to the spreading codes generated by AR filter are studied in this paper. Such as correlative character, codes balance, linear complexity.In order to practice the SESS communication system based on AR filter, the system must have the good performance of anti-jamming and multiple accessing. We analyze and simulate the AR-SESS communication model, the important performance factors, the Bit Error Ratio (BER) performance and the multiple accessing.