Research On High-Precision And Intelligent Transient Electromagnetic Receiving System Based On Embedded Technology

In recent decades,transient electromagnetic technology is widely used in metal minerals,oil resources,undergroundwater,geothermalenvironmental and engineering exploration.The development of electronics,computer science and communication science,makes transient electromagnetic instrumentsgo into development oriented with digitization,highaccuracy,high sensitivity,high intelligence,and network.There are certain defects in domestic transient electromagnetic instruments.Problems such as stability,synchronization in receiver,lower precision in data acquisition,weak capability in data processing,and large system power consumption,should be solved nowadays.In order to solve these numerous problems,there is a need to introduce the latest embedded technology to improve the overall performance of transient electromagnetic receiving systems.This paper includes the following four sections:1.Basic theoretical analysis of transient electromagnetic methods.2.System hardware circuit design,including ARM9 core controlling circuits and peripheral circuits.3.Thesoftware design of main control system,including Linux drivers and applications,CPLD program,Lab VIEW program and PC data handling procedures;4.Indoor and outdoor test on the equipment,analyzing the performance of instruments.The designs of hardware circuit include designs of AT91RM9200 ARM9 core controlling circuits,power conversion module,AD board analog circuit,AD board digital isolation circuit,AD conversion board ADC circuit,AD board self-test signal generating circuit,CPLD timing control circuit design,and high-precision clock circuit.The designs of system software include Linux drivers and applications programming,CPLD timing control procedures programming,Lab VIEW programming,VC PC programming and MATLAB data processing programming.Transient electromagnetic receiver system studied in the paper is combined with embedded ARM technology,Linux operating system software technology,24 high-precision A/D conversion technology,GPS synchronization technology,and other electronics and computer science results.Several laboratory and actual field tests show that the system is stable,reliable,and it acquires data with good results,thus the transient electromagneticreceiving system achieves the following targets:Lhigh-precision acquisition,24 median A/D acquisition;2.Synchronization,GPS and receiver are in synchronization;3.Portability,continuous observation of signal,portable,mobile and low-power;4.Low noise,equivalent input noise is better than 5uVpp;5.Large dynamic range,instantaneous dynamic rangereaches 120dB.