The Research On Impulse GPR Receiver Technique

Ground Penetrating Radar technique is a kind of electromagnetism technique using in underground mediam and underground objest location detection.It has great performance because that has high speed, it is contact free, it is anti-destruction and that it can display the results with pictures so that the underground situation can be analyzed directly.With these advantages, GPR technique has been used in many fields as geographical exploration, programme quality inspection, and many others.The transmitter of each kind of GPR has very little difference, so the differences of receivers are very important to the system, so that they determine the target recognization capabilities of the whole GPR system .For developing the most advanced national GPR, this paper researches deeply on the signal amplification, data transmission and other GPR receiver techniques of the feedback wave signal.Researching of transmitting characters and feedback wave signal characters in transient electromagnetic field, it is designed which is the special time-variable gain amplifier for the feedback signal, so the target recognization capability is rised; and it is designed which is a high speed data sample system for the feedback wave signal. Researching the working theory of USB equipment, it sets up the GPR feedback signal data transmitting scheme based on USB bus, designs the communication protocols for several signals composing by high speed and low speed signals, using the hardware sources as much as possible. It designs the experiment circuit of GPR receiver USB equipment which contains signal amplification, data sample and data transmission functions. Researched USB protocol and Windows operating system driver theory, the design of the GPR USB firmware and PC drivers and the client software are finished, it can display the detecting results in PC and control the working functions of machine.The project of GPR feedback signal data transmission based on USB bus could satisfy the requirement of GPR system, through the debugging and primary testing.