Research Of Data Transmission And Display Control In Imaging Sonar

With the development of marine industry，most countries are developing the technology ofunderwater detection. The imaging sonar is becoming more and more widely used in the underwaterdetection area due to its intuitive and real-time imaging ability.So the technology of imaging sonarbecomes a research focus in the current.Sonar system includes the following modules:transducer arrays,signal condition module,signalprocessing module,data transmission module and software module for displaying and controlling.This dissertation focuses on the design and implementation of the data transmission module andsoftware module.The detail work is as follows:1) Designing and implementing a gigabit Ethernet data transmission between sonar and computerbased on FPGA, focusing on improving the data transmission rate. On the FPGA chip,a SOPC systemis built and the VxWorks Operating System is transplanted for network programming. This part isfocused on the Ethernet interface hardware design, network card driver design and the optimization ofdata transmission performance. And according to the experimental tests, the data transmission ratereaches247Mbps,which is twice the design target.2)After analyzing the software requirement and dividing the software modules,the displaycontrol software is developed in the Microsoft VC++environment.The software implements all thefunctions of similar foreign software,such as image data receiving and real-time display, pseudo colormapping,image data record and playback,images and video export, distance measurement,etc.What’smore,it also can set the AE parameter and test sonar equipment.Due to the large amount of imagingdata,this part is focused on the large file processing technology, the sonar images’ real-time receivingand processing method,images conversion and zooming algorithm.By the research of these keytechnologies,the image quality is improved,and the processing and display rate is increased to3timesthe design target,which reaches22.1FPS of100meters range.Through the water tank testing,this imaging sonar system runs stably and reliably,and all themodules meet or exceed the design targets.The real-time sonar images got in the water tank verify thecorrectness of the design in this paper.