Research On De-hopping And Synchronization Technology Of High Speed Frequency Hopping System

With the rapid development of science and technology, electronic war has become the core of modern wars. It is the ultimate goal of the warring parties to grasp the initiative in the fierce electronic war. In the complicated electromagnetic environment, communication countermeasure appears particularly important in avoiding enemy’s interferences successfully, only in this way, the communication can be normally carried on with high-quality. When Frequency Hopping Spread Spectrum (FHSS) communication appears, it has attracted much attentions, especially in the field of military, because of its abilities of anti-jamming and anti-fading. Frequency Hopping Spread Spectrum communication can be carried out normally only in the support of synchronization. The receiver can correctly receive and demoldulate the data information under the condition of strict synchronization of both sides. Therefore, how to realize fast and accurate synchronization in high-speed FHSS system is a hotspot in the field of frequency hopping technology, and also an aporia.Under the background of project "XXXX system", this thesis mainly studies the de-hopping and synchronization of signals in high-speed FHSS system. According to the basic theories, it puts forward a design scheme for the high-speed FHSS system, and completes its modeling and simulation with Simulink software. Through the simulation, the system has realized its synchronization and de-hopping correctly. At the same time, the thesis also raises an improved scheme for synchronization-TOD self-synchronization method, which combines time of day(TOD) and synchronization-head. After, the thesis makes a model of FHSS system with TOD self-synchronization method, and the simulation results verify its effectiveness.Firstly, this thesis makes a systematic introduction of Frequency Hopping Spread Spectrum communication, specifically from the aspects of research backgrounds, research status and development trend, basic theories, technology advantages and key technologies. Then it intro-duces the synchronization technologies in details, including the theories of several commonly used synchronization technologies and their performance comparisons. Expect these, this thesis also puts forward a more suitable synchronization technology--TOD self-synchronization method for high-speed Frequency Hopping Spread Spectrum communication system and makes a theoretical introduction of its principles and performances. Secondly, this thesis gives a whole design scheme of high speed Frequency Hopping system according to the theories, carries on the modeling and simulation of the system from the overall to the part. The simulation results verify the feasibility of the system scheme and the accuracy of the system parameters.Next, this thesis makes a modeling and simulation for TOD self-synchronization method mentioned before with Simulink. The simulation results also validate the feasibility and effectiveness of the scheme.Finally, this thesis makes an overall summary about the finished work, points out the shortcomings and makes specific arrangements for next stage.