Simulation System Based On Dsp And Internet Technology, Vhf Hardware Design And Implementation,

With the development of simulation technology, Ship-handling Simulators play important roles in seafarer education and training. In order to realize more lifelike simulative environment, Ship-handling Simulator should have the function to interact and communicate between multinational ships. Therefore, Ship-handling Simulators located seperatedly around the world can be integrated through Internet that meet the demand of a simulated interational navigation enviroment. Then seafarers of different countries and regions can be trained together. The real-time voice communicate with VHF simulation system is an important part in this subject.Combined with the research and development of simulated VHF communication system of an Interantional collabration research project, Internet Based Integration of Multiple Ship Handling Simulators, this paper presents particularly argumentation, development and implementation of the VHF simulation system based on DSP and Internet. The research is focused on the study, selection and experimention of speech coding algorithms, the design of hardware circuit, the development of embedded control software, the programming and debugging of PC's interface and network transmission.The theoretics part of this paper is based on the multi-band excition algorithms. In the compression and decompression processing, tests and experiments to speech signal have been performed using MATLAB and DSP kit.There are two parts of the research work, software design and hardware design of the system, in this paper.The software design includes PC programming and microcontroller embedded programming. The hardware design includes the speech data sampling and reconstruction unit, encoder and decoder unit, data processing and transmission unit, clock synchronous unit, keyboard and display unit, and RS-232 converter unit.In the development process, Protel 99SE is used to design thehardware circuit. Verilog-HDL is used to model the synchronization circuit. The function of the model is simulated on Modelsim and synthesized on Synplify. In addition, this circuit model is also simulated on gate level with CPLD by ispLEVER. Furthermore, the real-time program for microcontroller is debugged with Keil. Program of network transmission for PC is compiled under Visual Basic6.0.This paper implemented the VHF simulation system based on DSP and Internet. It will help to enhance the function and scope of VHF training. The research and development of the system are as well significant to the application of multimedia communication in navigation education and other relative fields.YU Li-li (Traffic Information Engineering & Control)Directed by Shi Chao-iian Huang Zhen-min...