Research On Intelligent Anti-jamming Decision-making Method For Chaos Communication System Based On SDR

As a new development direction of confidential communication,the chaos communication system has broad application prospects in the military and civil communications field.The chaos communication system uses the chaos signal as the carrier during the modulation.Because it has a broad spectrum and lower power spectrum density,it can achieve the expansion effect,thereby enhancing the antiinterference ability of information transmission.In addition,the initial value of the unique to chaos signal makes it difficult to predict as a load,which can enhance the confidentiality of communication.However,as the electromagnetic environment is becoming increasingly complex,the open transmission medium of wireless communication makes it vulnerable to attacks from malicious interference signals,causing the chaotic communication system to face severe human interference threats,resulting in a serious decline in communication quality.Therefore,researching safe and reliable chaotic communication intelligent anti-interference decision-making methods has important practical significance.Differential Chaos Shift Keying(DCSK)system is a kind of confidentiality,robust security,and no need to send and receive synchronization of chaos communication system based on the software-defined radio(SDR)platform.This thesis studies the intelligent anti-interference decision-making method of the DCSK system and applies the reinforcement learning algorithm to the anti-interference decision-making of the DCSK communication system.Moreover,the reinforcement learning algorithm is applied to the anti-interference decision-making of the communication system through the learning of the environment of the system.According to the current interference situation,the parameters of the DCSK communication system are adaptively selected to achieve safe and reliable information transmission and improve the anti-interference ability of the system.The specific work is as follows:Firstly,a DCSK communication system with adjustable parameters is designed based on the SDR platform.Through the principle analysis of the DCSK chaotic communication system,the chaos signal generator,DCSK communication signal modulator/demodulator,adapted to the GNU Radio software-defined radio platform are designed and realized,and together with the supporting Universal Software Radio Peripheral(USRP),a DCSK end-to-end communication system with good performance and adjustable parameters is built,including transmitter,receiver and stand-alone transceiver module.It lays a foundation for intelligent anti-interference decisionmaking.Then,based on the designed DCSK communication system,a DCSK intelligent anti-interference decision-making method based on reinforcement learning is proposed.According to the four communication anti-interference parameters such as transmission power,communication channel frequency,and chaos signal type and initial value that affect the chaotic signal waveform,the method constructs the state space and action space of the decision-making system and designs the reward function according to the information transmission quality of DCSK communication,and completes the design and implementation of the decision-making system.Finally,a DCSK intelligent anti-interference experimental verification system based on the SDR platform is built.First of all,different types of malicious interference modules and spectrum perception modules are designed,and the DCSK communication system,interference module,and intelligent anti-interference decision-making system are integrated by Python.An experimental verification platform is built to verify the anti-interference performance of the DCSK intelligent anti-interference decisionmaking system in different interference scenarios.Experimental results show that the intelligent anti-interference decision-making method of DCSK communication proposed in this paper has an excellent anti-malicious interference effect,and the DCSK communication system can effectively resist frequency point interference and blocking interference without significant change in transmission power to ensure the safe and reliable transmission of information.The DCSK communication intelligent anti-interference decision-making system designed in this paper can provide a basis for safe and high-quality wireless communication in practical application scenarios.