Geological Radar Two-dimensional Finite Difference Time Domain Forward

In period late of 20 century, the technology of ground penetrating radar acquiring basically development, just after the high frequency microelectronics technique and calculation technique get quick development. Because it is a exploration technique of not breaking the original property, and its ability of anti-electromagnetism interference is strong, therefore it can be work well under the environment of the all kinds of noise interference, the environment interference is small, too. It possesses the satisfactory exploration depth and distinguish rate in engineering, can offering the real time section record in the locale directly. The diagram clears, intuitionist. The convenient schlepping microcomputer controls the data collected, storage and handle, and the work efficiency is high, repetition is good. Ground penetrating radar (GPR) have so many advantage, therefore applied very extensive. But now it still exist some proportion to waiting for improvement, for example, distinguishing the GPR diagram primarily stays in the foundation of the artificial naked eye distinguish and handcraft identify. Therefore it is beneficial to us to understand the electromagnetic wave spreading regulation, and scoop out much more useful information from the GPR wave inside, through forward simulate the familiar penetrating object in physical.At first, in this text author set out analysis from Maxwell equation group, and put great emphasis on the two vortices equation of Maxwell equation group. Application K.S.YEE 's space grid model, and the utilize center difference coefficient substitute for the differential coefficient. We can disperse the spatial continuous variable, regularization the electric field, and obtain the two dimension spatial time-domain finite-difference equation, which is the GPR forward simulate equation we request deducing. For guaranteeing the arithmetic accurate, we analyze the numerical value's stability and discussion question of numerical value frequency dispersion to the two-dimension TM electromagnetic wave (GPR wave), deduce out numerical value's stability expression and ideal frequency dispersion relation. At the same time in order to prevent the radar simulation model wave at the truncated boundary strong reflection.We deduce out the super absorb boundary condition, and make use of the condition into the self-regulating program write by C language, and obtained the good effect.In this thesis we discuss GPR *.dzt file format, and put great emphasis point on analyze radar *.dzt head file format. On basic of clearly understand the *.dzt file format. The head file and the data obtain by running and simulating the self-regulating program are been written into the file of *.dzt radar format using the function-base fwrite in C language. Afterward we transmit the *.dzt file of radar format into the radar dispose software that the machine equip, and get the wave diagram from several familiar formula model. The waves of imitate result and the waves of practical penetrate fit well. It proved that the finite-difference time-domain (FDTD) method can reach good effect in GPR forward simulate, besides the result of using finite-difference time-domain (FDTD) method forward simulate the GPR model have important guidance meaning for the engineering practice. Additionally finite-difference time-domain (FDTD) method calculating program have the extensive currency character in electromagnetism field. The program can be exerted only needing modification a little of relevant parts aim at different problem or different calculation object. Therefore the program of us authorized have a few of reference value to the electromagnetism field simulate operator.