To a multibeam echo sounder system (MBES), under water sound refraction plays an important role in depth measure- ment accuracy, and errors in sound velocity profile lead to inaccuracies in the measured depth (especia...To a multibeam echo sounder system (MBES), under water sound refraction plays an important role in depth measure- ment accuracy, and errors in sound velocity profile lead to inaccuracies in the measured depth (especially for outer beams). A method is developed to estimate the sound velocity profile based on the depth measured by vertical beam. Using this depth and other pa- rameters, such as t (sound pulse propagation time), θ (beam inclination angle), etc. We can estimate a simple sound velocity profile with which the depth error has been reduced. This method has been tested with a real dataset acquired in the East China Sea.展开更多
The caustic lines are formed as envelop lines of wave rays on the complex topo- graphy where conventional ray theory fails.By using the inner and outer scale method in the near region the caustic lines the singulariti...The caustic lines are formed as envelop lines of wave rays on the complex topo- graphy where conventional ray theory fails.By using the inner and outer scale method in the near region the caustic lines the singularities of the ray theory are dealt with.Using the conclusion that the phase of the ray in contact with the caustic line increases by π/2,the whole wave refraction problem is solvec except on caustic lines.展开更多
基金funded by the National High Technology Research and Development Program of China('863'Program)under contract Nos.2004AA616080 and 2006AA09ZI03the National Natural Science Foundation of China(Project code:40606026).
文摘To a multibeam echo sounder system (MBES), under water sound refraction plays an important role in depth measure- ment accuracy, and errors in sound velocity profile lead to inaccuracies in the measured depth (especially for outer beams). A method is developed to estimate the sound velocity profile based on the depth measured by vertical beam. Using this depth and other pa- rameters, such as t (sound pulse propagation time), θ (beam inclination angle), etc. We can estimate a simple sound velocity profile with which the depth error has been reduced. This method has been tested with a real dataset acquired in the East China Sea.
文摘The caustic lines are formed as envelop lines of wave rays on the complex topo- graphy where conventional ray theory fails.By using the inner and outer scale method in the near region the caustic lines the singularities of the ray theory are dealt with.Using the conclusion that the phase of the ray in contact with the caustic line increases by π/2,the whole wave refraction problem is solvec except on caustic lines.