The Design And Implementation Of Deep-sea Data Forwarding System

The development of the deep sea is of very vital significance to the implementation of the ocean strategy, and of great significance to the sustainable development of Marine economy. The environment under the sea is complex and changeable, hydrological monitoring equipment, AUV, unmanned submersible vehicles are important tool of human to know the deep sea. These tools monitor the sea about the depth, salinity, temperature, flow velocity, terrain and so on, so there are a lot of valuable data produced need to be spread to the land for storage and analysis by a reliable data transmission system.According to the requirement above, this paper designed a deep-sea environment data forwarding system, including subsurface buoy and buoy two parts. Its function is to forward the data as acoustic spread spectrum signal collected and stored by CTD and ADCP to the buoy on the surface of sea through the underwater acoustic channel; and after the buoy received acoustic spread spectrum signal, it would send the data demodulated to PC on the land through the satellites, and finally it realized the purpose of remote forwarding the deep-sea environment monitoring data. The system designed processed automatically without human intervention, it cost less compared with traditional data forwarding system.The main work of the paper concludes: designing of the system overall project, consist of parameter designing, system structure project and hardware project, choosing a kind of cabin using in deep-sea, and using A3LA-RG Iridium satellite module to realize the satellite communication function. The paper designed the hardware circuit of the system, including on-duty board, ARM digital-signal-processing board, power board, and bottom board. The paper designed MSP430 programs, including MSP430 on-duty program, serial port communication program and Iridium satellite communicate program. According to the spread spectrum arithmetic DLL, the paper designed the ARM application program, including data storage, board-to-board communication program, and Iridium satellite controlling program.Did the electronic debugging, experiment in water tank and experiment in the sea.In the electronic debugging, the author test the performance of the hardware sufficiently,test the software as well, proved that the system could realize the data forwarding function.The experiment in water tank, measured the transmitting sound level of the system, the result satisfied the design. Experiment of function test proved that the system could realize the data forwarding function. Experiment in the sea, consist of horizon communication experiment,vertical communication experiment and Iridium satellite communication function testing experiment. The horizon communication experiment proved that water tightness of the cabin and stability of the system satisfied the design. The vertical communication experiment proved the conclusion further. Last experiment,the PC received the e-mail with ocean environment data accurately,proved that the path of data forwarding is expedite,and the system can realize the data forwarding function.