Considering the uncertain effects of temporal and spatial changes in the marine en- vironment on the underwater acoustic environment, we established an ocean-acoustic coupled numerical model and performed a parallel c...Considering the uncertain effects of temporal and spatial changes in the marine en- vironment on the underwater acoustic environment, we established an ocean-acoustic coupled numerical model and performed a parallel calculation. This model incorporated acoustic calcu- lations into the dynamic ocean, thereby achieving a dynamic forecasting and assessment of the acoustic environment. Furthermore, we adopted the ensemble prediction method to predict the vertical structure of temperature in a classic cross-section, the sound speed of the cross-section of the investigated sea area, and transmission losses. We gave the prediction errors of the sound speed profile as well as the 90% probability interval of transmission losses and the uncertainty histograms of the sound speeds, transmission losses, and sonar ranges at different depths and frequencies. The results reflected the influence of marine temporal and spacial variations on the uncertainties of the underwater acoustic environment, and the results also quantified the uncertainties of the underwater acoustic environment parameters. The experimental results indicate that the method used in this study is able to delineate and quantify the uncertainties of the underwater acoustic environment caused by marine dynamic changes.展开更多
In order to meet the demands of underwater acoustic communication in under ice environment,a differential Pattern time delay shift coding underwater acoustic communication method based on parametric array is introduce...In order to meet the demands of underwater acoustic communication in under ice environment,a differential Pattern time delay shift coding underwater acoustic communication method based on parametric array is introduced in this paper.The under ice underwater acoustic channel is characterized by heavy multipath transmission.Under this model,a parametric array emission method of Pattern signal is derived and the system performance is analyzed.A broadband low frequency sound waves with narrow beam-pattern,which will reduce the interface reflections and suppress the effects of multipath transmission,can be obtained by the emission method.The Songhua River under ice trial results show that there is an anti-multipath property and a higher data rate in the under-ice acoustic channel in proposed approach.展开更多
基金supported by the China Postdoctoral Science Foundation(20110491884)the General Armament Department Pre-research Project(9140A03060213JB15039)
文摘Considering the uncertain effects of temporal and spatial changes in the marine en- vironment on the underwater acoustic environment, we established an ocean-acoustic coupled numerical model and performed a parallel calculation. This model incorporated acoustic calcu- lations into the dynamic ocean, thereby achieving a dynamic forecasting and assessment of the acoustic environment. Furthermore, we adopted the ensemble prediction method to predict the vertical structure of temperature in a classic cross-section, the sound speed of the cross-section of the investigated sea area, and transmission losses. We gave the prediction errors of the sound speed profile as well as the 90% probability interval of transmission losses and the uncertainty histograms of the sound speeds, transmission losses, and sonar ranges at different depths and frequencies. The results reflected the influence of marine temporal and spacial variations on the uncertainties of the underwater acoustic environment, and the results also quantified the uncertainties of the underwater acoustic environment parameters. The experimental results indicate that the method used in this study is able to delineate and quantify the uncertainties of the underwater acoustic environment caused by marine dynamic changes.
基金supported by the National Natural Science Foundation of China(61471137,61631008)Fok Ying Tung Education Foundation(151007)the 13th Five-Year Plan Communication Information Control and Security Technology Key Laboratory Foundation(61421060301162106001)
文摘In order to meet the demands of underwater acoustic communication in under ice environment,a differential Pattern time delay shift coding underwater acoustic communication method based on parametric array is introduced in this paper.The under ice underwater acoustic channel is characterized by heavy multipath transmission.Under this model,a parametric array emission method of Pattern signal is derived and the system performance is analyzed.A broadband low frequency sound waves with narrow beam-pattern,which will reduce the interface reflections and suppress the effects of multipath transmission,can be obtained by the emission method.The Songhua River under ice trial results show that there is an anti-multipath property and a higher data rate in the under-ice acoustic channel in proposed approach.
