Research On Through-the Earth Spread Spectrum Communication System For Mine

Low-frequency Trough-the-Earth communication for mine is seen as the most secure way of production and emergency communication because of its channel character not affected by emergency. However, the research and development of it is not yet satisfied due to several technical puzzles. In this case, the aim of this paper is to establish a communication system for coal mine.The characteristics of mine through-the-earth communication channel are analyzed and summed up, together with its simulation model in System View is set up; based on which a project using spread-spectrum technology of mine through-the-earth communication system is proposed firstly, then the principle and performance of this system project are analyzed by use of theory analysis and simulation, the results demonstrated that the system scheme is practicable and effective, which is fundamental to the chip design. Lastly, a novel method of chip design is explained, and its main modules are designed and simulated on the platform Max+Plus II., the principle graph is given as well.Based on the analysis of characteristics of mine through-the-earth communication channel, a simulation model in System View is set up, and aiming at difficulties of mine communication, a project of mine through-the-earth communication system using spread- spectrum technology is proposed for the first time, which is realizable digitally. Theoretical analysis and whole simulation of it are carried out, and the results demonstrate that the scheme is practicable and effective, which is fundamental to chip design. Then a special chip for mine through-the-earth communication is designed using the method of hierarchy design, whose main modules are designed and simulated on the platform of Max+Plus II., and finally the top principle figure is given as well.The most outstanding characteristic of the proposed scheme is its full digitalization. It can accomplish several functions such as data encoding, spread spectrum modulation, demodulation and etc. It is an advanced integrated and digitalized project that has an advantage over others. Project analysis and modularization are realized by use of simulation software, each module is implemented by the combination of VHDL and principle figure, and the initial design of the chip is accomplished making use of hierarchy design methodology.