Study On Chaotic Security Communication Based On QCSK Modulation And DSP Implement

Chaos widely exist in objective world.The study of Chaos is one of the most important work for non-linear subject.With going deep into Chaos, Chaos control and the realization of it is advanced problem in this field. This thesis go deep into study of QCSK and the application of encrypted communication in chaos system,and have finished the Chaos encrypted communication of DSP hardware and software based on QCSK Modulation-Demodulation.Chaos signal is not random ,but is likely random .It is non-periodic, broadband frequency spectrum and noiselike.The movement of Chaos signal is abnormally complex and unpredictable.So it is covered inartificially. Chaos signal is adapt to be the carrier of encrypted communication. Generally speaking, Chaos encrypted communication express information as waveform or bit stream in sender;and recover the right signal from the received singnal in receiver. Chaos signal is the information carrier in Common Channel,this signal usually act Chaos system signal as synchronization sender and receiver . In addition, Chaos system is determinate in substance. It is decised by non-linear equation , parameter and initial conditions,so it is prone to engender and copy a large mumber of irrelevant and conducted Chaos Sequence. The noise-like, unpredictable yet deterministic orbits and sensitivity of Chaos signal make it be the same with encrypted communication . Chaos encrypted communication require sender and receiver Chaos system synchronization .So Chaos synchronization become the key problem and impotant theoretical basis Chaos encrypted communication . Pecora and Carroll first realize Chaos system synchronization form theoretical and experimentation in early 1990s,there are many synchronization method come true.There have been severy Chaos synchronization control method can conclude .This dissertation's main content is as follows:In chapter one, it is summarized the history and method of research of chaos, and basic knowledge and characteristics of chaos. Because of its nice performance chaos will be applied to communication and many other domains.In chapter two, some technologies of chaotic communication such as chaotic analog communication, chaotic spreading spectrum communication and chaotic keying demodulation, have been introduced .Completes the theory upholstery for the behind thorough research chaoscorrespondenceIn the chapter three, has studied the privacy communication system synchronized questionwith emphasis, As for two same chaos systems, so long as the starting value has theslight difference, two systems space's path can rapidlyseparate. Soon, The two space's path completely is not related. Although two chaos systems chaoses attract the actor's opening words space are possibly completely consistent, But two space's path actually is unable synchronization. Therefore chaos system synchronization theory proposing theapplication research has the epoch-making significance regarding thechaos in the correspondence.In the chapter four, we introduce the software implement of the QCSK modulation chaotic secure communication system based on the DSP. The hardware partial mainly introduced in the experiment uses Central processing module, Pronunciation gathering and return to original state module, Logic control module,and Data and procedure memory module. Software partial mainly introduced based on the DSP chip codeproduction and the debugging tool CCS, And has compiled the chaos signal production, the pronunciation signal QCSK modulation and the demodulation in its platform, as well as to the logical control and the disposition programming which internaloutside supposes.In the chapter five, the running result of each program is summarized and the results are compared with that of producing by. At last, we analyze those results and run the QCSK modulation chaotic communication system in real time. Simultaneously had also pointed out will be insufficient and the nextimprovement direction.In the last chapter, we summarize the total dissertion and point out the direction of the research of application of chaotic communication and thequestion needed to resolve in future.In this dissertion, we exploit preliminarily the realization of hardware and software of QCSK modulation chaotic communication system based on the DSP and design the scheme of the transmitting and receiving part of the system, which will be helpful for the succession.