Design Of Acoustic Detection Vector Array Acquisition System

With the improvement of stealth level of underwater vehicle,acoustic detection vector array acquisition system with higher sensitivity is needed to complete the detection of underwater targets.For the collected signals,it is necessary to have its adapted data storage system.In this thesis,a vector array acquisition system for underwater acoustic signals is designed,which is composed of a timing unit based on "ARM+FPGA" architecture,an acquisition unit based on "ARM+FPGA+ADC" architecture,and an attitude measurement system using ARM as a control chip.According to the need,from the hardware,programming two aspects of design.In terms of hardware,the signal conditioning unit performs band-pass filtering and program-controlled amplification for low-frequency underwater acoustic signals.The data acquisition unit realizes4 channel signal synchronous acquisition,transmission and storage;FPGA controls AD chip and receives data,and carries out command and data interaction with ARM;Time unit FPGA realizes the reception of 6-array metadata through time division multiplexing.ARM is responsible for the logic control,data storage and communication between the whole system and the upper computer.The attitude measurement system measures and records the vector array attitude.SD card stores data,command,data and PPS communication between acquisition unit and time system unit.The program is mainly oriented to the actual function of the hardware development,FPGA based on VHDL language to write,ARM based on C language to write.The low frequency underwater acoustic signal is adjusted,collected and stored synchronously,and the vector array attitude is measured and stored by the attitude measurement system.In this thesis,combined with the results of lake tests,the functional test and power consumption test of each unit are completed,and the stability of the acoustic detection vector array acquisition system is verified.