Standard Network Based On The Vector Potential Underwater Target Positioning System Key Technologies

In underwater acoustic techniques,underwater target positioning technology plays an important role.First,the paper analyzes the generation mechanism and the general characteristics for the ships radiated noise.And it also analyzes the relationship between the main noise distribution、the frequency and speed of navigation.Further discussion of the item used in the mathematical model and simulation of the physical meaning of each parameter and the correlation between each other.The paper give several noise simulation methods,which proves the feasibility of this model.For the subsequent signal processing algorithms need ship radiated noise generation should do the theoretical preparation.Second,the paper discusses the direct sound extraction technology,on the basis of a detailed study of the broadband and narrowband signals precision delay measurement technique.For wideband signal taken generalized cross-correlation technique;and for narrowband signals,the coherent accumulation first adaptive line enhancer (ALE) for signal enhancement techniques,based on this technology Adaptive Notch coarse delay between the measurement signal difference and phase difference information, to obtain an accurate delay information.Finally, the use of computer simulation of the effectiveness of the related art. Around two common hierarchical model for sonic velocity correction techniques carried out relevant research and formula derivation proposed ray tracing algorithm positioning system processes,and the use of actual test data to verify the effectiveness of the algorithm.Finally,according to the system functional requirements as well as requirements of these indicators,the paper adopted a DSP+FPGA-based hardware architecture to the digital signal processing module to design,FPGA to realize the system timing control, digital signal preprocessing (eg FIR filtering, FFT operation),various. interface conversion functions,the DSP implementation system replica correlation or cross-correlation and envelope detection and other signal processing tasks;this way can take full advantage of the high degree of parallelism and FPGA real-time,and can be fully using the DSP signal processing capabilities,making the system flexible structure,computing ability, versatility.Paper presents the vector potential target system hardware implementation,the system used by the DSP HPI bus for communication with the host.DSP EMIF Bus Gets the FPGA through the analog-digital conversion of data,or digital to analog conversion will be required to send data to the FPGA.Thesis focused for low frequency amplification section and testing equipment parts design, testing,and inspection.Frequency amplifier board for amplifying the transducer array from a weak signal,and its beam forming, amplification and frequency conversion processing for converting into an intermediate frequency signal buffer amplifier BA,an important part of the system. Some of the major studies testing equipment FPGA logic design.