Improved Chaotic Sequence Generation Method Based on Direct Spread Spectrum

Abstract

Aimed at the shortcomings of one-dimensional chaotic sequences as spread spectrum address codes in DS/SS(Direct Sequence Spread Spectrum) communication system, such as low complexity, simplicity of generation and easy to be estimated backwards, etc, an improved chaotic sequence is proposed, which is composed of two one-dimensional chaotic maps and the fractal parameter of one map is controlled to control the fractal parameter of another map in a certain mathematical form. Then the performance analyses of the sequence are carried out from the angles of complexity, correlation, randomness and anti-interference ability. The results of simulation show that the improved chaotic sequence not only improves the complexity obviously, but also has good correlation and randomness, and the anti-interference ability in DS/SS communication is more prominent.