The Design And Implementation Of Underwater Acoustic Data Compression And Storage System

The underwater acoustic target recognition technology relies on the richness of the training sample library.In order to obtain the target radiation noise sample library data,the submarine target placed on the seabed is usually used for long-term data collection.The traditional data acquisition latent standard directly stores the sampled data in the memory,and extends the acquisition working time by expanding the memory space.This paper starts from improving the utilization of data storage space,and uses lossless compression technology to design and implement an underwater acoustic data compression storage system,which can improve the utilization of latent data storage space and achieve the purpose of extending the storage time of latent data.The thesis first conducts theoretical research and simulation analysis on the lossless compression technology of underwater acoustic data.The focus is on the entropy coding techniques such as decorrelation technology based on linear prediction,Huffman coding,run-length coding,LZ series coding and Golomb-Rice coding.After simulation comparison,Golomb-Rice coding is selected as the coding technology for lossless data compression.The single-channel data compression performance of the vector hydrophone and the correlation between the joint channels are simulated and analyzed,combined with the actual working conditions of the target radiated noise acquisition by the latent target,and the dynamic process compression simulation analysis is performed.Second,the paper designs and implements the hardware of the data acquisition system.The designed data acquisition hardware mainly includes signal conditioning module,acquisition storage compression module and power supply module.According to the actual needs of the data acquisition and compression storage module,the heterogeneous platform ZYNQ 7Z020 is selected as the main processor,combined with peripheral circuits to complete the system acquisition and compression storage function.Then,based on the research results of the lossless compression technology of underwater acoustic data,the paper designs the software of the compression storage system on the ZYNQ platform and writes related programs.It mainly includes logic programming on the PL side and embedded system software programming on the PS side.The PL end is responsible for data collection,packaging and caching.The PS end is responsible for data sub-packaging,compression and file storage on the basis of running the Linux operating system.PL and PS carry out data transmission through the internal AXI bus and interrupt system.Finally,the function test of the underwater acoustic data compression storage system is carried out.The test focuses on the equivalent input noise,channel consistency,interface communication function,power consumption,data storage speed,reliability,compression and decompression functions of the circuit.The test results show that the underwater acoustic data compression storage system meets the design index requirements.In the actual lake test and verification,the actual collected data was tested and analyzed for compression ratio.The analysis results showed that the data compression ratio reached 38.04%,which can improve the utilization of system storage space and achieve the purpose of extending the storage time of latent target collection.