Study On Anti-jamming Technology And Realization Of Intermediate Frequency Signal Source For Link16

Link16 is a kind of tactical data link integrated the functions of communication, navigation and identification and developed by U.S army for the purpose of joint operations among navy, land force and air force. The anti-jamming techniques adopted by Link16 include cyclic redundancy check(CRC), forward error correction coding, interleaving, cyclic code shift keying(CCSK), minimum shift keying(MSK) modulation, time hopping(TH) and high speed frequency hopping(FH). It has the advantages of large capacity, high data rate, good security and strong anti-jamming ability. Based on the study and simulation of the key techniques and anti-jamming performance of Link16, the thesis which relies on projrct XX of China Electronics Technology Group Corporation NO.XX research institute, completes the design, FPGA realization and system test of Link16 intermediate frequency signal source according to the requirements of the project.Firstly, the thesis presents the basic composition of Link16 system and its technical characteristics, analyzes the time division multiple access(TDMA), message packing structure and time slot type, and then focuses on the analysis of the generation process of transmission waveform of Link16.Secondly, the anti-jamming techniques are analyzed, model built and simulated respectively. Among all the techniques, we mainly focus on the study of CCSK sequence and wide interval FH sequence. The self-correlation and error performance of two kinds of CCSK sequence is simulated and compared. Based on prime number sequence, wide interval FH sequence is designed and completed according to the protocol of Link16. A simulation model of Link16 system is built by using Matlab/Simulink.Thirdly, to solve the problems of wide dispersion and low utilization of jamming power in the fixed interference like wide and partial spectrul band jamming, comb block jamming, a new dynamic interference called FH collision jamming is proposed. The anti-jamming performance of Link16 with these three types of interference is simulated and compared. Aimming at different kinds of jamming, the corresponding anti-jamming measures in Link16 are analyzed and summarized.Finally, based on digital realization of the submodule including CRC, random interleaving, CCSK, MSK, generation of transmission symbol and FH control word, the design and FPGA realization of Link16 signal source are completed. After the simulation of Link16 siganl source, a test platform is built for the test of the project indexes including TDMA, message packing structure, MSK modulation and date rate. The results show that Link16 intermediate frequency signal source designed in the paper works stably and all the test parameters meet the requirements of the project.