Research On Spread Spectrum Code Synchronization Of Chaotic Spread Spectrum Communication System

The spread spectrum communication has been widely used in the field of communication and military for its advantages of anti-jam, anti multi-access and good concealment and so on. M and Gold sequences are used in the direct sequence spread spectrum communication(DS-SS), but both of them have the limitation of length and number in some sense. These more or less impact on the performance of communication system. The direct sequence spread spectrum communication is divided into two categories of coherent and incoherent system. Coherent direct sequence spread spectrum communication’s robustness and bandwidth efficiency are better than incoherent under noise. Coherent chaotic spread spectrum communication system not only inherits the advantages of direct sequence spread spectrum communication system, but also improve the safety of system and the capacity of spread spectrum code.This paper starts from the basic theory of spread spectrum communication and chaos theory, and elaborate the basic knowledge and characteristics of direct spread spectrum communication and chaos. Secondly, this paper focus on analyzing the related properties of sequence, and simulate the chaotic sequence. In order to compensate for the disadvantages of the reverse iteration of the conventional sequence, a hybrid chaotic sequence is proposed and introduced into the spread spectrum communication system. In order to reduce the channel fading effect on communication system, interleaver and deinterleaver will be used in transmitting terminal and receiving terminal. Assume the channels of communication system are Gauss, Ruili and interleaving fading channels respectively. I will simulate and analysis the system to prove the feasibility of coherent chaotic spread spectrum comminication. Using the interleaver and deinterleaver has good effect on the improvement of system performance. It has a certain reference value for research and development of the spread spectrum communication, and it is conducive to promoting the development of chaotic communication.