Research And Design Of Transmission Unit Of Impulse GPR

No carrier frequency ground penetrating radar is using transmitting antenna to the ground by launching a very narrow pulse nanosecond, re-echo and scattering wave is received through the receiving antenna, after signal processing and then be a useful signal to reflect the end of the technology of underground conditions. It has a very wide range of applications, detection of the road foundation, archaeological, underground pipeline investigation, rivers, lakes, dams danger detection, earthquake and other aspects of life, the search is very important applications. Therefore, GPR research and improve the performance of the hardware system has a very important practical value. This paper examined the status of ground-penetrating radar and working principle, for non-penetrating radar carrier frequency transmission unit requirements, research and design of the non-transmitting carrier frequency ground penetrating radar unit and receiver unit. This paper follows the work done:(1) Using the principle of series voltage regulator and innovative use of knowledge of analog circuits, design of the output from the wide range between 80V and 280V output and wide range of inputs, in theory, the ripple factor of less than 5mv, the actual measurement is less than 20mV ripple high voltage DC power supply, power supply simulation design is given and the actual measurement results.(2) Depth study of the principles of avalanche transistor, using FPGA to propose a strict timing of each other as the avalanche transistor trigger pulse to trigger pulse to get to meet the stringent timing pulse and arbitrary waveform synthesis method.(3) For carrier frequency control of ground penetrating radar system and the need for complex signal processing front-end features, using FPGA to present a complete timing control, using DSP to complete signal processing algorithm, and through the USB2.0 to achieve data communication with the host computer to achieve high integration, hardware and easy updates of GPR data acquisition unit method. FPGA implementation is presented and verified FPGA control and interact with the DSP method, Give full play to the final design of the respective characteristics of DSP FPGA with small practical easy to implement hardware updates GPR Data Acquisition System, and gives the actual measured results. (4) Writing FPGA control procedures and giving the simulation and measurement; Writing firmware,firmware automatically download drivers,drivers and application; in the DSP to write a control program and a number of digital signal processing procedures.