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Study On Theory Of Sound-source Bearing Estimation With Motion Acoustic Array Based On Brainpower Submunition

Posted on:2010-02-27Degree:DoctorType:Dissertation
Country:ChinaCandidate:S X SunFull Text:PDF
GTID:1102360275498851Subject:Artillery, Automatic Weapon and Ammunition Engineering
Abstract/Summary:PDF Full Text Request
Based on the application background of brainpower antitank submunition, the theories and applications of localization and tracking of acoustic target on the ground are studied with motion acoustic array. All basic problems involved by motion acoustic array are discussed, including preprocessing of signal, study on acoustic array shape, the elements which affects the localization accuracy, etc. Multi-scale time delay estimation(TDE), localization algorithm of motion acoustic array and bearings-only tracking of maneuvering targets on ground with BAT are studied on emphasis. The main research contents are as follows.The fundamental localization theories involved by acoustic array are studied at first. The basical problems of acoustic array are summarized. The theoretical system of motion acoustic array is established combining the requirement of the paper. Some elemental problems in BAT application are analyzed, such as source model, simplified algorithm model of acoustic velocity, nonlinear modify model of propagation velocity, delay modify model of tracking, absorption to different frequencies of air, etc. Aiming at un-consistent characteristics among different microphones, a self-adjusted recognition method for higher characteristic microphone is given. Signal processing of acoustic array is studied, some effective preprocessing and post processing methods of signal are proposed, which enhances the localization stability of acoustic array and becomes the basis and premise of following studies.The essential theory of localization and localization ability of acoustic array are studied, which provides BAT for selecting proper acoustic array shape and establishes the basis for improving the localization algorithm of motion acoustic array. The essential principle of localization of acoustic array is analyzed. Given the relationship of localization and fixed distance of acoustic array, the relationship formula of any array is deduced, which presents that to improve localization accuracy is to improve fixed distance accuracy. The localization abilities of different array shape are compared with the same conditions. The least square localization algorithm of pyramid acoustic array is proposed. The errors of localization and fixed distance of pyramid acoustic array are analyzed, which is verified by experiment. On the basis of acoustic array theory, the multi-target combining localization theory is discussed on the ground of acoustic target, which can measure the coordinate of spot and velocity. According to above analysis, squared array is proper for BAT.The TDE theory is studied. The multi-scale TDE based on empirical mode decomposition(EMD) is proposed, which decomposes signal as plenty of IMFs. The multi-scale time delay values are got by cross-correlation of different IMF. The similar criterion of wave in frequency(SCWF) and vector matching criterion of time delay estimation(VMCTDE) are proposed for selecting the accuracy TDE from plenty of multi-scale time delay values auto-adapted, which makes the multi-scale time delay applicable. The multi-scale time delay based on wavelet decomposition is improved and perfective. The conclusion that wavelet decomposition will not change the intrinsic time delay values of signal is proved, which gives specific mathematic principles for multi-scale method based on wavelet decomposition in application of TDE. The accuracy time delay value can be got by VMCTDE. The experiments present that multi-scale decomposition can remain the high-frequency of signal and enhance TDE accuracy, which can be applied broadly when the signal is nonlinear and the correlation noises exists among different channels.The localization theory of motion acoustic array is studied on emphasis. The concept of motion acoustic array is proposed. The motion acoustic array is decomposed into maneuvering acoustic array and rotating acoustic array. The de-maneuvering localization algorithm of maneuvering acoustic array is proposed. The localization formula and accuracy analysis formula are given. The simulation test presents that this algorithm can be applied in the localization of maneuvering target Because rotating acoustic array is nonlinear and rotating velocity affects localization accuracy badly, the de-rotating localization algorithm is proposed. The localization formula and accuracy analysis formula of de-rotating localization algorithm are given. The simulation presents that this algorithm reduces the limit of rotating velocity in some extend.The bearings-only tracking of BAT submunition is studied. The bearing information series with error is estimated with only acoustic array. The distance estimation formulas of BAT when targets are static or moving on the ground are deduced. Position information of target can be estimated based on bearing information series and unknown height of projectile. The estimation of distance is premise of tracking further. On the basis of above researches, the tracking method of 2-D maneuvering target is studied with 3-D motion carrier. The bearings-only tracking algorithm is proposed when the angle has error. The sufficient conditions of tracking all information of the target are given. Because of redundance confilict of angle information series to bearings-only tracking, multi-scale sequential Kalman filter is introduced to bearings-only tracking theory, which solves the conflict and enhances tracking accuracy.
Keywords/Search Tags:acoustic array, brainpower antitank submunition, passive localization, bearing estimation, time delay estimation, direction-of-arrival, bearings-only tracking, multi-scale decomposition
PDF Full Text Request
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