Design Of Data Acquisition And Transmission System In Four-element Acoustic Vector Subsurface Buoy Array

Marine background noise is a very important data indicator in ocean observation and ocean experiment.It is very important to study the background noise of marine environment.The purpose of this paper is to design the acquisition and transmission system in the acoustic vector subsurface buoy,and the four-element acoustic vector subsurface buoy array can observe the background noise of the marine environment with different depths in the same location.The acquisition and transmission system filter the sound pressure,Vibration speed of the vector hydrophone signals.These signals can be acquired synchronously,storaged and uploaded to the shore station in real-time.So this system can real-time monitors the marine environment background noise changes.The design of the acquisition and transmission system in the four-element acoustic vector subsurface buoy array consists of hardware and software.The hardware design includes analog part and digital part.The digital part includes a digital acquisition module,a data storage module,a clock synchronization module,a duty module and a data transmission module,which collects and stores the analog signal that real-time uploaded to the surface buoy.The system central processing chip is DSP,and uses the synchronous second pulse to trigger the data acquisition of the four-element acoustic vector subsurface buoy array.The CF card is used as the storage medium to storage the data;subsurface buoy array communicate with surface buoy by RS-485 serial port;MSP430 as a duty circuit is responsible for the system command recognition and data transmission.The software design of the system realizes the functions: self-test,synchronization,acquisition and storage,data reading and data upload.The self-test function ensures that the peripherals of the system are in normal working state.The synchronization function allows four vector primitives to acquire the marine environment background noise information in different depths at the same time;acquisition and storage functions will converts analog signals into digital signals for easy to store and recycle;data read and upload functions can upload collected data to the surface buoy in real-time,and then upload to the shore station.This system has been debugged and tested in both laboratory and ocean environment,and meet the design requirements.It collected the background noise of the marine environment in the relevant sea area.Successfully,the real-time data collected and uploaded to the shore station realized the goal of observing the background noise of the marine environment in real-time.