Underwater target localization and parameters(azimuth and range) estimation by the method of utilizing explosions as underwater sound sources are described in this paper.The narrow beam reverberation model of the targ...Underwater target localization and parameters(azimuth and range) estimation by the method of utilizing explosions as underwater sound sources are described in this paper.The narrow beam reverberation model of the target echo signal is researched to estimate the target azimuth in reverberation background.Estimation errors of target azimuth and range are studied and proved to approximately meet Gauss distribution.Then the variance formula of target range error is deduced.Simulation experiments are applied to research the target range error and its standard deviation,and a series of measures to improve the estimation accuracy of target range are proposed.It is confirmed by the data processing results of simulations and lake experiments that the proposed method can accurately locate underwater target at a long distance on the condition of a certain underwater explosion range error.展开更多
The one-dimensional theory of sound propagation in ducts is generalized and investigated in this paper . It can be assumed that any duct system consists of two kinds of elementary structures : One is the piped structu...The one-dimensional theory of sound propagation in ducts is generalized and investigated in this paper . It can be assumed that any duct system consists of two kinds of elementary structures : One is the piped structure in which the characteristics , such as the acoustical parameter on the interior surface of the wall , the cross-section area and the aerodynamic parameters of the flow , etc., will vary continuously and slowly with distance along the axis of the duct . The other is the local structure with discontinuity in which the characteristics will change abruptly. The acoustical properties of both structures are analysed in general cases based upon the fundamental equations of aerodynamics , and their transmission matrixes are derived and discussed respectively . Two typical examples are analysed and discussed .展开更多
基金supported by the National Natural Science Foundation of China(61431020,61571434)
文摘Underwater target localization and parameters(azimuth and range) estimation by the method of utilizing explosions as underwater sound sources are described in this paper.The narrow beam reverberation model of the target echo signal is researched to estimate the target azimuth in reverberation background.Estimation errors of target azimuth and range are studied and proved to approximately meet Gauss distribution.Then the variance formula of target range error is deduced.Simulation experiments are applied to research the target range error and its standard deviation,and a series of measures to improve the estimation accuracy of target range are proposed.It is confirmed by the data processing results of simulations and lake experiments that the proposed method can accurately locate underwater target at a long distance on the condition of a certain underwater explosion range error.
文摘The one-dimensional theory of sound propagation in ducts is generalized and investigated in this paper . It can be assumed that any duct system consists of two kinds of elementary structures : One is the piped structure in which the characteristics , such as the acoustical parameter on the interior surface of the wall , the cross-section area and the aerodynamic parameters of the flow , etc., will vary continuously and slowly with distance along the axis of the duct . The other is the local structure with discontinuity in which the characteristics will change abruptly. The acoustical properties of both structures are analysed in general cases based upon the fundamental equations of aerodynamics , and their transmission matrixes are derived and discussed respectively . Two typical examples are analysed and discussed .
