Researth On Multi-beam Sounding Sound Velocity Correction Method

Ocean accounts for more than two-thirds of the entire Earth’s surface, she is rich in naturalresources, at the same time,shi is also responsible for the human hopes for the future.Accompanied by increasing levels of human life, the land resources is dwindling, mankindmust seek for new sources, then human beings will turn their attention to sea of rich naturalresources. Oceans not only provide the necessary natural resources for mankind, but alsoserve for scientific research. The marine scientific research in humans, the development ofmarine resources utilization and marine engineering design and construction process, in-depthunderstanding of complex seabed topography is to carry out the basis and premise of theabove work, measurements of the seafloor topography, the speed of sound correction accuracydetermines the seabedthe accuracy of the topographic survey, it is necessary to explore andstudy the speed of sound correction, in order to improve the measurement accuracy of themulti-beam seafloor topography.This paper discusses the composition of multi-beam bathymetric system, soundingmechanism and the impact of voice-bending factor analysis on the basis of the relatedtechnologies must be used to track the correction of bending phenomenon on changes in themarine environment arising from the voice,thereby increasing the multi-beam bathymetricprecision. Comparative analysis of calculation in the conditions of different water parameters,the five classic sound velocity model formula, the optimal speed of sound formula fordifferent waters. Understanding the Argo program and its data format and download way tocalculate the sound speed profile of the study area to provide sources of data; two multi-beamecho sounding sound velocity correction method, the average speed of sound correction andsound line track correction method, two sound velocity correction method of mathematicalmodels and computational principles, while the sound velocity of the ray tracing method tocorrect the calculation process; example,Argo data according to the study area combined withthe classic model of the optimal speed of sound, using two sound velocity correction method for multi-beam bathymetric speed of sound corrections to study computing.The paper base on the sea profile of Argo official website in the study area, calculate toget two different sound speed profile, the use of average speed of sound law and sound raytracing method for different sound speed profiles, different beam angle of incidence two ofthe study area, the simulation and analysis to the speed of sound correct shows that: thesounding value of the precision layering and sound ray tracing method (50m per level) can beseen as equivalent when the accuracy requirements is not the case, that is,multibeam seafloortopography measurement, the value of the ray tracing method to calculate the depth of theseabed can be seen as the true depth value. The average speed of sound method of submarinedepth value with the true depth of the deviation is relatively large. Under the same soundingparameters, that is the same as the propagation time, the same angle of incidence of beaminitial depth value calculated based on the sound speed profile of the study area there is a bigdifference, that is, different waters in the same measurement time, the measured water depthvalue is different; when the initial angle of incidence of the beam emitted by the multi-beamsounding system, the correct average speed of sound on the speed of sound, you can still gethigh sounding accuracy, However, when the initial beam angle of incidence smallermulti-beam sounding system launched, if not the speed of sound track speed of soundcorrection, the edge of the beam bathymetric results existence of large-sounding error. Canalso prove that when the initial angle of incidence of the beam emitted by the multi-beamsounding system, even if divided into thickness, the final depth value through the speed ofsound correction accuracy is also very high.