Design And Application Of The Acoustic Communication System

The acoustic communication technology is one of the most complex technologies and the acoustic communication becomes a pop research field because of the complexity of the marine channel. This paper bases on the'Drill acoustic communication system'which is under the subject of'Development of gas hydrates deep-sea shallow hole pressure and temperature holding core Drill'of the National 863 program (Hi-tech research and development program of China) resources and environmental technology fields. The system achieves to monitor Drill at the sea bottom and transmission real-time data without armored cable condition. It's has great significance that acoustic communication system ensures the Drill working normal. Acoustic communication system has an expansive apply foreground at the deep-sea measurement, such as SVP measurement, heat flow measurement and marine magnetic force measurement. I am one of the mostly attendees at the project of the'Drill acoustic communication system', and take charge of the acoustic modem, protract graph, the assistant design of the acoustic communication system, compile report and attend the debugging on the sea and so on; attend the sea survey of the SVP and the heat flow measurement.Firstly the article expatiates on the basic knowledge and the development of the acoustic communication for the mastery of the acoustic communication system laid the foundation. Then, the domestic paper expatiates on the status of the acoustic modem and the comparison among different acoustic modem products. And explains why the UWM 4000 acoustic modem as a basis to establish for acoustic communication system is the inevitable choice. Also describes the function orders of the UWM 4000 in detail, which lays a foundation for the achievement of the acoustic communication system.Acoustic communication system is mainly made up of deck-monitoring unit, underwater acoustic communication modules and underwater monitoring-control unit. Deck-monitoring unit plays the role of data exchange between deck-monitoring computer and surface acoustic modem, and processes the receiving data, separates different types of signals to be converted into normal record, according to the prearrangement data packet format. Acoustic Communication units accomplish the signals conversion from digital signal to acoustic signal or acoustic signal to digital signal. Underwater monitoring-control unit completes the data collection of Drill working at the sea bottom, provides data packets according to the prescribed data formats, and sends them to acoustic communication units to receive and transmit. With the sea debugging, it shows that Acoustic communication system can monitor the work status of the pressure-temperature holding system.Next the article introduces the application of acoustic communication system at the deep-sea survey and the widely foreground. In the application of the pressure and temperature holding core Drill, it briefly introduces the overall structure of the Drill, main technical indexes and functions, and focus the work principles and methods of automatic monitoring system, finally introduces the application at the Drill of the acoustic communication system in detail; In the application of SVP measurement, it introduces the apply purposes and technical indexes of the SVP instrument, and further expatiates on the design of the hardware and the apply results. In the application of the heat flow measurement, it summarizes the status, characteristic and the apply circs at the survey of the gas hydrates at the heat flow measurement, then introduces the apply circs at the heat flow measurement.Finally, the article summarizes the issues on the results achieved in the course of the study and the application and foreground of acoustic communication system:1) Establish a set of acoustic communication system for deep sea temperature-pressure holding drill by directly adopting mature and stable, low-cost acoustic modems.2) The first time to apply the home-made acoustic communication system to transmit the SVP and heat flow data in China, Which has an active significance. And it has a widely apply foreground at the deep-sea survey.