Research On Data Acquisition And Transmission System Of 3D Imaging Sonar

Not only does China have vast land territories,but also vast sea areas,the development and utilization of marine resources is of great significance to the development strategy of China’s maritime powers.Sonar imaging systems have a wide range of applications in underwater detection.Sonar data collection is an important part of the imaging process of sonar systems.With the increase in imaging requirements,sonar imaging systems have also proposed higher synchronization and accuracy of data collection Requirements.The three-dimensional sonar data acquisition and transmission system developed in this subject can effectively perform synchronous data acquisition and transmission,and has high engineering application value.The main research contents of this article are as follows:1.Research on multi-channel synchronous data acquisition scheme.The overall scheme of real-time synchronous acquisition of 256-channel underwater acoustic data through two master and slave acquisition boards was studied and designed;the synchronization methods and influencing factors of the master and slave acquisition boards were analyzed separately.Research and propose a hardware synchronization scheme based on multi-level clock distribution.Independent modules are designed to generate high-precision synchronization signals,and the synchronous clock drive system is optimized to reduce clock skew and obtain better clock pulse characteristics,thereby improving the synchronization of multi-channel data acquisition and achieving the Second-level synchronization accuracy.2.Research on data transmission scheme.Research and design a high-speed real-time synchronous transmission system for underwater acoustic image data based on Gigabit Ethernet;analyze and optimize the data transmission data stream format and data buffer storage mechanism;research and propose a multi-level data cache scheme based on message arbitration,and implement The message construction and real-time transmission of about 500 Mb / s underwater acoustic data stream.The software for receiving underwater acoustic data was developed on a computer platform,and a data processing scheme based on a multi-threaded,multi-level queue buffer mechanism was proposed.It can analyze the data stream transmitted by the acquisition system in real time,simultaneously extract underwater acoustic data,buffer and store the data.The problem of packet loss during high-speed underwater acoustic data transmission is well solved.3.Based on the proposed hardware and software solution of the acquisition system,a complete data acquisition and transmission system and computer software were developed,and a complete experimental verification and performance testing platform was established;a 100 k Hz synchronous acquisition and transmission test of 256-channel underwater acoustic data was completed.The verification test results show that the system scheme proposed in this paper can achieve simultaneous sampling and transmission of 256 channels of underwater acoustic data;the packet loss rate during system transmission is close to zero,data acquisition phase consistency,amplitude consistency,short-circuit noise,and system power Consumption etc.meet the requirements.