The Research Of Acoustic And Pressure Wave & Tide Measurement

The ocean wave and tide observation is significant to disaster prevention, mitigation, resources exploitation and people’s livelihood. At present, the main wave observation is by buoy while tide observation is by tide gauge well in our nation. However, buoy and tide gauge well have high operating cost, moreover buoy can be easily damaged and tide gauge well does not fit in the mud shallows. The coasts in our nation are variable within 20 meters, some of which are mud bottom. This article tries to design a combine system of acoustic and pressure measurement suitable to our nation coastal.In the beginning a new design idea is introduced based on the current observation status by analyzing advantages and disadvantages of pressure, acoustics, buoys, radar wave. The design includes the composition, functions and workflow. The wave and tide theory section discusses the wave computing method, tide measurement influence, temperature compensation in acoustic measurement, air pressure compensation in pressure measurement, spectroscopic analysis. The hardware section discusses the hardware sensors, data acquisition implementation and then introduces the design principle of acoustic measurement including sound generator, acoustic transmitters and receivers, computing and storage circuit. The software section discusses the program process including data reception, processing, storage and display.Experiment section includes a comparative analysis of wave characteristic values, tide characteristic values, spectrum and the compensation method of acoustic and pressure measurement. The results showed that: the data of acoustic wave devices, pressure device and buoy has a good correlation. The acoustic device is capable of measuring small period waves and pressure wave devices works well under the impact of crushing waves. The two of them can complement each other. Innovative points in this article are as follows:(1) Acoustic measuring and pressure measuring complement each other, expanding the device range and measurement accuracy. Acoustic wave measurements can overcome the depth limit of pressure wave measuring instrument while pressure wave measurements overcome the environment requirements. The combination of them can solve the needs of our coastal, island and platforms wave measurements.(2) The device is flexible to fit marine stations, engineering survey and oceanographic survey. Sampling frequency and work mode can be settled. Sampling frequency can be selected from half an hour, one hour and three hours. Work mode can be selected from pressure measurement mode, acoustic measurement mode an acoustic pressure measurement mode.