This Is "the Application And Study On The Method Of Adjusting The Sound Velocity Of The Multi-beam Bathymetric System"

Starting from scientific requirement of the sub-subject (multi-beam bathymetric survey on EW(Q) zone) of the national specialized project, known as"survey on the northwest pacific ocean bottom", the author has completed all the work from theoretical research on the method of sound velocity correction to the simulations based on various methods, from analyzing the characteristics of sound velocity profile of the sand ridge in the eastern sea to its influence on bathymetric. By applying the algorithms of sound velocity correction to the data processing in the multi-beam survey, research on the method of sound velocity correction and its application in correcting seabed topographic characteristics of the sand ridge area in the eastern sea are completed.Since environment factors influence the bend of sound ray directly, the accuracy of sound velocity profile and its correction algorithm will affect multi-beam bathymetric accuracy. How to track sound ray of the multi-beam bathymetric in real-time and establish correction methods for different environment have become a hot pursuit in multi-beam bathymetric. Mainly from the point of data processing, research on how to correct the bend of sound ray is carried out, application results show that it has good quality.Based on the analysis on how various sound velocity structure affect the bend of sound ray, the author proposes that sound velocity profile measured on the spot should be carefully analyzed, and corresponding measures and techniques be applied to process the original acquired data, in order to improve the correction accuracy of bend of sound ray. Based on the statistics induced by the analysis of the current sound velocity classical formulas, an optimized formula fit for different water depth will be acquired. Experiments in shallow water prove the formula is right and possess the possibility of practical application. An depth-oriented acoustic ray tracking technique used to supplement the acoustic velocity has been worked out to improve the depth measuring precision. In light of the relationship between the sound velocity and depth demonstrated by the distribution curve, a methmatics model to track sound ray is built. The precision of sea-bed depth and corresponding postion measuring can be greatly improved by applying the sound ray tracking technique. Considering the defects of sound ray tracking technique, an adjusted model of equivalent sound velocity profile technique is proposed. The computing procedure for adjusting the sound velocity is presented, the advantages and disadvantages of which also are analyzed. Based on the results of the survey on multi-beam in EW(Q) zone, the corrected materials get processed. Focusing on the characteristics of the time-space construction of survey area, the sound ray tracking and equivalent sound profile techniques are respectively adopted to correct the sound velocity data acquired through on spot multi-beam measuring, which greatly reduces the measuring error.