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Study On Signal Processing Method Of Suppressing Typical Interference Imposed On Pseudo-random Code Phase-modulation Fuze

Posted on:2007-01-02Degree:DoctorType:Dissertation
Country:ChinaCandidate:S N ZhangFull Text:PDF
GTID:1102360185991839Subject:Mechanical and electrical engineering
Abstract/Summary:PDF Full Text Request
The anti-jamming ability of fuze affects the life of fuze, which is now being faced with increasingly complicated interference environment in the modern war, so how to improve the anti-jamming ability of fuze is one of the most important problems in the fuze field. In this dissertation, several typical interference suppression methods based on signal processing for typical radio fuze—pseudo-random code phase-modulation (PRCPM) fuze is studied. The contents involved in this dissertation are subordinated to a key preparatory project granted from the national defense. The productions obtained from this dissertation are valuable for the related PN systems such as communication and radar. The main contributions are as followings:(1) The forms and features of several kinds of typical oppressive FM interferences are analyzed. The influences of the above FM interferences on the correlation output of PRCPM fuze are studied quantitatively.(2) The Fractional Fourier Transform (FRFT) result of LFM interference is deduced. To suppress LFM interference imposed on PRCPM fuze, the method of filtering in fractional Fourier domain is proposed. The implementation procedure of suppressing mono and multi-component LFM interferences in fractional Fourier domain is given. The output SJR after interference suppression in fractional Fourier domain is analyzed. At last it is confirmed by simulation that the mono and multi-component LFM interference imposed on PRCPM fuze can be effectively suppressed via the above method.(3) To suppress multi-component FM interference of PRCPM fuze, the method of adaptive time-varying interference cancellation based on DEHT is proposed. The signal discrete evolutionary transform form based on overlapped orthogonal basis expansion is analyzed. The instantaneous phase of interference is estimated by the Hough transformation of DET spectrum and segmental recursive correction. The adaptive time-varying interference canceler is designed according to the estimated interference instantaneous phase. At last it is confirmed by simulation that the above method can effectively suppress multi-component LFM and SFM interference imposed on PRCPM fuze.(4) The method of interference suppression based on twice square transformation is presented to suppress mono-component FM interference imposed on PRCPM fuze. Taking the NFM interference for an example, the interference suppression principle based on twice square transformation is clarified. The output SJR after interference suppression is...
Keywords/Search Tags:PRCPM fuze, Interference suppression, Fractional Fourier transformation, Discrete evolutionary Hough transformation, Twice square transformation, Envelope filtering, Wiener filtering in Wavelet domain, Orthogonal projection
PDF Full Text Request
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