Gain Analysis Of Deep-sea Reliable Acoustic Path Vector Hydrophone Array

In recent years,the study of acoustic propagation characteristics and the application of vector hydrophones in deep sea environment has been paid more and more attention.It is of great significance to study the vertical correlation characteristics of deep-sea vector field under reliable acoustic path to improve the gain of vertical bursts.This paper studies the sound propagation characteristics of the reliable sound path,adopts the vector field sound propagation model derived from the ray theory,and studies the influence on the effective detection range of RAP-based targets through the changes of sound pressure,horizontal and vertical vibration velocity and RAP parameters.The effects of acoustic frequency,receiver location,ocean depth,submarine medium,seasonal influence and sound velocity distribution on reliable sound path are analyzed.The detection distance of reliable sound path can be maximized when the receiver is located at critical depth.By analyzing the results of this part,the location and depth of the hydrophone can be rationally selected in target detection based on reliable sound path.Combined with the effective detection distance of RAP under different environmental parameters,the vertical correlation characteristics of vector hydrophone vertical array under the effective detection distance are analyzed,and the correlation between array distance and receiving distance,sound source frequency,sound source depth,receiving depth and vertical vibration velocity of each array is analyzed.The vector field correlation formula is used to analyze the mechanism of correlation change through the grazing Angle at the receiving end,the propagation loss of vertical vibration velocity,and the delay and amplitude of the received signal at the receiving end,and then the correlation analysis is carried out on the typical seabed topography in the central basin of the South China Sea.It is found that the correlation coefficient between sound pressure and sound pressure,the correlation coefficient between sound pressure and vertical vibration velocity,and the correlation coefficient between vertical vibration velocity and sound pressure have obvious periodic oscillation with the change of array spacing at the horizontal distance of 2～15km.Through analyzing the distribution mechanism of vertical correlation coefficient for the grazing Angle,delay and amplitude of the received signal at the receiving end,it is also studied that the correlation between the sound pressure and the vertical vibration velocity of each array element of the 16-element vector vertical array is higher than that between the sound pressure.The vertical correlation between the receiving ends increases with the number of oscillating fringes generated by the array spacing.As the depth of the source increases,the vertical correlation between the receiving ends increases with the number of oscillating fringes generated by the array spacing.The gain of the vector matrix is studied.The gain of the vector matrix is close to 0d B when the interval of the matrix is 0～2.5m.Because the array gain at the vertical velocity is limited by the effective detection distance of RAP,the signal gain at the horizontal distance of 2-10 km will be much higher than that at the horizontal distance of more than 10 km.The average signal gain in the range of 2-10 km horizontal distance and 2-20 m array spacing is the maximum region of signal gain,and the signal gain in this range is about 1.235 d B higher than that in the range of20-80 m array spacing.In the range of 0-80 m,the average signal gain in the horizontal range of2-10 km is about 2.72 d B higher than that in the region of horizontal distance greater than 10 km.The research in this paper can provide theoretical guidance for the layout of vector vertical array in deep sea..