Researched On Construction Of Spread-spectrum Code Combined On Chaos With Self-coded Theory

With the rapid development and wide application of communication technology, how to ensure quickly transmission of communication information effectively and accurately in the harsh environmental conditions, is increasingly becoming a key issue to be solved in communication. Spread spectrum communication technology is a new means of communication in the modern communication system, is a core technology in the third generation personal communication system.Since conventional spreading code sequence period is short,low complexity,poor security and a limited number of coding defects.In this context,In this paper,studying a method of construction algorithm of the spread-spectrum code based on chaos and self-encoded and another construction algorithm of the spread-spectrum code based on perfect sequence set,and to study its relevant characteristics,complexity and randomness applied in spread spectrum communication error rate characteristics.The main work is as follows:First,study a construction algorithm of the spread-spectrum code based on Logistic chaotic and the self-encoded,we propose a new complex symbol sequence, AR-self-coded and complex fusion of two random sequences,this three random sequences performance analysis test, and then to get a high quality compound spread spectrum code by the nonlinear Henon mapping fusion with self-coded sequence and applied to the spread spectrum communication.Improved anti-jamming capability of communication systems to ensure the accuracy and effectiveness of communication and information transmission.Second,propose a construction algorithm of the spread-spectrum code based on piecewise logistic chaotic map and the self-encoded,the method uses of structure thought discrete standard mapping and two-dimensional Henon transform,to improve two-dimensional Henon map,and combined it with the AR self-coded sequence to generate a high quality composite random sequence as spreading code,which to be used transmission of communication in the spectrum communication,to ensure the safety and reliability of signal transmission.Third,propose a construction algorithm of the spread-spectrum code based on complex multi-scroll Jerk-Chua chaotic and the self-encoded,quoting structure thought two-dimensional Henon transform and discrete standard mapping to generate a high quality composite random sequence as spreading code,and used to information transmission in the spread spectrum communication system,greatly improves the security of the spreading code and the complexity of the system,able to meet transmission of information security under high security and dynamic changing conditions.Fourth, in order to solve the problem of short period and low-complexity in traditional spread spectrum sequence,a method of constructing spread-spectrum code based on perfect sequence set is proposed.In this method firstly a perfect sequence set of long period and high complexity is obtained by using binary ideal autocorrelation sequence through the algorithm of shift.A spread spectrum code is then set by random sampling row or column sub-sequence of perfect sequence and used for spread spectrum communication.The effectiveness of this method is analysed based on traditional pseudo-random sequence and Logistic chaos sequence.Compared with the conventional method,this method can improve correlation of sequence and increase complexity of sequence.Simulation test show that the perfect sequence has strong noise immunity,and can also obtain a lower spread bit error rate.