Research On Easy Encoding Communication Method And Signal Reconstruction Based On Analytically Solvable Chaotic

Chaotic signals are generated by deterministic systems and show more complex motion patterns.In view of the complexity of chaotic movement,the traditional idea holds that there is no analytical solution to chaos.However,some scholars have derived a large number of theoretical deductions to find a class of chaotic systems with analytic solutions,abbreviated as analytically solvable chaotic systems(ASCS).The analytical solution of the chaotic system not only describe the chaotic signal accurately,but also use the analytical solution to give the matched filter of the corresponding system,so as to achieve the maximum signal-to-noise ratio of the output signal.Therefore,the research of ASCS has significant application value in practical engineering of chaotic communication.This thesis is based on the ASCS,focusing on the encoding method of chaotic communication and the signal reconstruction of chaotic signal processing.The main innovations and works are as follows:(1)Focusing on the issue that the traditional information encoding methods have high computational complexity,a simple and effective information encoding method based on the reverse-time chaotic system(RTCS)is presented in this paper.The method encodes the transmitted message into a bipolar sequence to drive the RTCS directly,in order to generate a chaotic signal suitable for channel to transmit,so then avoiding the problem of information encoding’s high computational complexity.In order to maximize the signal-to-noise ratio of the receiver’s output signal,this paper presents the analytic expression of the matched filter of the basis function of the RTCS,which reduces the influence of noise interference effectively at the receiver.The bit error rate(BER)is basically the same as that of the traditional information encoding method under Gaussian white noise channel and the same signal noise rate(SNR),but the method given in this paper is simpler.The anti-noise performance of it is better than differential chaos shift keying(DCSK)under Rayleigh channel conditions.(2)Focusing on the issue that signal reconstruction using chaos synchronization is very difficult to realize under strong noise conditions.According to the derivation,we can deduces that there is a specific function relationship between the analytic expression of HCS(category of analytically solvable chaotic systems)and RTCS.Based on the above analysis,a new signal reconstruction method is proposed based on ASCS,which solves the problem that it is difficult to achieve signal reconstruction in chaotic synchronization under strong noise conditions.The signal reconstruction method given in this paper has better signal reconstruction performance than traditional signal reconstruction methods under strong noise conditions.