Key Technology Study On Data Acquisition And Processing Of Underwater Acoustic Signals

Taking Water Depth Monitoring System for Port Channels as background and in view of the characteristic of acoustic emitted in the research, we take MCU and FPGA as core control units, designed an acoustic signal acquisition and processing system suitable for engineering project which is based on GPS time synchronization technology. This system is an important part of the Water Depth Monitoring System and has an important meaning.The core of acoustic signal data acquisition and control is FPGA. The timing circuit design of FPGA is based on VHDL language. The main task of FPGA is to control the timing of ADC and FIFO cooperates with each other in order to achieve high-speed acquisition and storage of underwater acoustic signal. This data acquisition and processing system is placed on one side of the channel, and the launch transducer is placed on the other side of the channel, in the aspect of synchronization technology we take GPS modules. The MCU on the launch transducer and the data acquisition and processing system read the GPS time information at the same time. At a certain moment, the launch transducer and the data acquisition and processing system start at the same time, thereby bringing about the acoustic signals in the remote synchronous acquisition.Acoustic signal processing is achieved by the MCU. After the data acquisition is completed, MCU reads the data in the FIFO, and take it for the short-term energy analysis to judge the beginning and end point of the signal, and then send the effective data of acoustic signal and the beginning point of the signal to computer by VHF module.Experiments and tests on the system show that the data acquisition and processing system is stable, reliable, low power consumption, high accuracy and very practical. The system has broad application prospects in the acoustic signal acquisition and processing.