Design Of The Indoor Detection And Calibration Equipment For MRS Groundwater Investigation

Water is one of the most valuable natural resources for the survival of human being. To solve the water crisis, high-tech investigation of groundwater has become an urgent task. Currently, the only direct detection of groundwater is the ground geophysical methods MRS. However environment electromagnetic noise (1 kHz to 3 kHz) influence the MRS water detector significantly, in particular in indoor detection. This paper firstly introduces the demands of MRS instrument for indoor detection and then analyzes the electromagnetic noise, to provide equipment that can detect whether the function of MRS instrument is normal and a detected method in the simulation of the field in the indoor experimental conditions. This equipment can detect and calibrate the MRS instrument system. The design includes some main module, such as analog MRS signal generator, electromagnetic shield box and upper computer software. First the equipment generates the analog MRS signal, then MRS instrument detects the signal that has attenuated by resistances and space coils. Finally the computer gets the data then compares results with the parameters that have set before; thereby we can proof the accuracy of the amplifier and collection cards.This thesis included seven chapters and it introduces the indoor detection and calibration equipment in detail.Chapter 1 is the introduction. Firstly, stated the theory of magnetic resonance sounding (MRS). Secondly, it analyzed the development of domestic and overseas researches, finally gives the content and meaning of the paper.Chapter 2 is the design of the overall structure of the indoor detection and calibration equipment. The overall design scheme of the equipment is given according to the function. Chapter 3 is the design of the analog MRS signal generator. It stated the design of the main chips interface, memory address assignment, and communication module and communication protocol in detail.Chapter 4 is the design of the electromagnetic shield box, it introduced characteristics of the electromagnetic shielding, choose of shielding material and design of the inter frame. At last it gave the tests of electromagnetic shield effect.Chapter 5 is the design of the upper computer software. It mainly stated the function of upper computer software, the design thought and the operation of software.Chapter 6 is mainly about a lot of indoor tests for the self-detection mode, the key parameters calibration mode, and the testing capacity of amplifier and collection cards. Finally, analyzed and explained the results of tests.Chapter 7 is the conclusion of this paper, summarized the research and look forward to the future work.Through system testing, the indoor testing and calibration equipment prototype is normal working, stability and accurate measuring, which achieved the expected objective of the basic design.