Study On Parameter Extraction And Jamming Effectiveness Of Typical Pseudo-random Code Fuze

Pseudo-random code fuze is an important development direction of radio fuze for its better performances, such as low altitude performance, strong anti-jamming ability, precise detecting distance and velocity performance.How to analyze and evaluate the jamming effectiveness of the pseudo-random code fuze objectively, accurately and quantificationally, as well as how to improve jamming and anti-jamming ability is an important project concerned about by the two parties of fuze countermeasure in scientific research, production and testing, etc. In this dissertation, method for extracting characteristic parameter of the three typical pseudo-random code fuzes, namely pseudo-random binary phase coded continuous wave fuze, pseudo-random code phase modulation and sine frequency modulation (PRCPM-SFM) compound continuous wave fuze and PRCPM-SFM compound pulse train fuze,is studied.Based on this, jamming effectiveness on oppressive and deceptive jamming is studied and major factors of influencing jamming effectiveness are analyzed,at the same time, jamming effectiveness on oppressive and deceptive jamming is evaluated quantificationally. The research provides theory foundation for the two parties of fuze countermeasure on improving jamming and anti-jamming ability, meanwhile, the productions obtained from this dissertation are valuable for studying the pseudo-random code fuze and other system fuzes further. The main contributions are as followings:(1) Acorrding to the providing principle block diagrams of pseudo-random binary phase coded continuous wave fuze, PRCPM-SFM compound continuous wave fuze and PRCPM-SFM compound pulse train fuze, the working principle of the three kinds of fuzes is analyzed, and their signal forms from launcher, receiver to signal processor are deduced.(2) Method for extracting characteristic parameter of the three typical pseudo-random code fuzes is studied based on ZAM distribution, the specific algorithm of extracting pseudo-random code sequence parameters, sine FM parameters, pulse width and pulse repetition period is provided. The influence coming from noise is discussed by simulation while extracting these characteristic parameters.(3) The receiver models of the three pseudo-random code fuzes are set up respectively, according to the receiver models, the jamming effectiveness of oppressive noise frequency modulation(NFM) jamming and noise amplitude modulation (NAM) jamming is analyzed, and major factors influencing the jamming effectiveness are discussed based on the criterion of signal to jamming ratio (SJR) gain. The jamming effectiveness of deceptive jamming is analyzed based on the value of the correlator output under the deceptive jamming environment, and the primary factors influencing deceptive jamming effectiveness are also analyzed.(4) Methods of evaluating oppressive jamming effectiveness based on starting probability and evaluating deceptive jamming effectiveness based on successful deceptive probability are put forward.The starting probability of the three kinds of typical pseudo-random code fuze is defined, and their starting probability is deduced under oppressive NFM jamming and NAM jamming. Major factors influencing the starting probability are discussed and the oppressive jamming effectiveness is evaluated based on the starting probability. The successful deceptive probability of the three kinds of fuze is defined, and primary factors affecting successful deceptive probability are analyzed.Moreover, the deceptive jamming effectiveness is evaluated according to the successful deceptive probability.(5) The system model of the pseudo-random binary phase coded continuous wave fuze receiver is set up by making use of simulink simulation software, and the factors influencing both oppressive and deceptive jamming effectiveness on the pseudo-random binary phase coded fuze is studied by simulation.In the absorbing chamber, the oppressive and deceptive jamming experiments are carried out for the principle sample machine of pseudo-random binary phase coded continuous wave fuze with the help of radio fuze experiment jammer system, and the conclusion of the research mentioned above is approved.