The horizontal-longitudinal correlation of the sound field decreases rapidly in the shadow zone of the deep sea,which severely limits the detection performance of the horizontal array in this area.This paper employs a...The horizontal-longitudinal correlation of the sound field decreases rapidly in the shadow zone of the deep sea,which severely limits the detection performance of the horizontal array in this area.This paper employs a range-frequency interference structure to frequency-shift compensate the acoustic field at different longitudinal intervals to improve the horizontal-longitudinal correlation of the acoustic field in the shadow zone.Firstly,the range-frequency interference structure and the horizontal-longitudinal correlation are analyzed by simulation based on a deep-sea experimental environment,and the simulated horizontal-longitudinal correlation of the acoustic field is improved through frequency-shift compensation by using an equivalent waveguide invariant.Then the experimental acoustic data from the deep-sea experiment is analyzed.The horizontal-longitudinal correlation of the received acoustic field in the first shadow zone at three depths and two ranges is processed.The data processing results show that the horizontal-longitudinal correlation length after frequency-shift compensation is increased by approximately 4 to 11 times compared to before the frequency-shift compensation.The simulated and experimental results demonstrate that the use of a range-frequency interference structure for frequency-shift compensation of the received acoustic field can effectively improve the horizontal-longitudinal correlation of the sound field in the shadow zone of the deep sea.展开更多
While using the bottom bounce mode to detect deep-sea shadow zone,the signal-to-noise ratio decreases due to the influence of the seabed reflection loss on the signal,which poses great difficulties for target detectio...While using the bottom bounce mode to detect deep-sea shadow zone,the signal-to-noise ratio decreases due to the influence of the seabed reflection loss on the signal,which poses great difficulties for target detection.Therefore,this article establishes a signal model based on the propagation law of sound in deep-sea shadow zone and analyzes the multipath structural characteristics of signals in shadow channels.Based on the principle of generalized likelihood ratio test,the detector suitable for target detection in shadow zone is designed according to the single beam multipath structural characteristics and spatial beam splitting characteristics.The simulation results and real data processing results both indicate that the proposed detector has significantly improved detection performance compared to traditional matched filter detectors by extracting and utilizing the multipath structural features of the echo of the shadow zone.展开更多
基金supported by the Goal-Oriented Project Independently Deployed by Institute of Acoustics,Chinese Academy of Sciences(MBDX202101)the Hainan Provincial Natural Science Foundation of China(123MS105)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0700100).
文摘The horizontal-longitudinal correlation of the sound field decreases rapidly in the shadow zone of the deep sea,which severely limits the detection performance of the horizontal array in this area.This paper employs a range-frequency interference structure to frequency-shift compensate the acoustic field at different longitudinal intervals to improve the horizontal-longitudinal correlation of the acoustic field in the shadow zone.Firstly,the range-frequency interference structure and the horizontal-longitudinal correlation are analyzed by simulation based on a deep-sea experimental environment,and the simulated horizontal-longitudinal correlation of the acoustic field is improved through frequency-shift compensation by using an equivalent waveguide invariant.Then the experimental acoustic data from the deep-sea experiment is analyzed.The horizontal-longitudinal correlation of the received acoustic field in the first shadow zone at three depths and two ranges is processed.The data processing results show that the horizontal-longitudinal correlation length after frequency-shift compensation is increased by approximately 4 to 11 times compared to before the frequency-shift compensation.The simulated and experimental results demonstrate that the use of a range-frequency interference structure for frequency-shift compensation of the received acoustic field can effectively improve the horizontal-longitudinal correlation of the sound field in the shadow zone of the deep sea.
基金supported by the National Natural Science Foundation of China(E211130101).
文摘While using the bottom bounce mode to detect deep-sea shadow zone,the signal-to-noise ratio decreases due to the influence of the seabed reflection loss on the signal,which poses great difficulties for target detection.Therefore,this article establishes a signal model based on the propagation law of sound in deep-sea shadow zone and analyzes the multipath structural characteristics of signals in shadow channels.Based on the principle of generalized likelihood ratio test,the detector suitable for target detection in shadow zone is designed according to the single beam multipath structural characteristics and spatial beam splitting characteristics.The simulation results and real data processing results both indicate that the proposed detector has significantly improved detection performance compared to traditional matched filter detectors by extracting and utilizing the multipath structural features of the echo of the shadow zone.
