Development Of Spectrum Induced Polarization Receiver

Spectrum induced polarization(SIP)receiver is a data acquisition system developed for SIP,a geophysical exploration method,to collect and process related data.At the beginning of this research,by studying the domestic and foreign spectrum induced polarization receivers,the paper puts forward some technical requirements on acquisition accuracy,time synchronization,endurance ability and so on,and determines the development scheme of the receivers.In this graduation project,according to the requirements of the national 12 th FiveYear 863 project "high-power well-magnetotelluric imaging system",the hardware development work has been carried out,including:(1)the ARM9 processor has been developed as the core control module of the whole system to control the realization of acquisition function and data transmission;(2)the regulated power supply module has been developed for integration.(3)The clock module is developed to output highprecision and stable clock source to the whole system by receiving GPS signals and cooperating with OCXO and related circuits;(4)The channel module is developed to realize the analog-to-digital conversion of acquisition signals,and the related analogto-digital conversion circuit is designed for each signal input to ensure the acquisition accuracy;(5)The signal processing is developed.The module filters out some interference signals to ensure the quality of data;(6)The spatial structure of the whole instrument is designed to meet the needs of field work.After completing the hardware development work,the program development of host computer and host computer is carried out,which mainly includes:(1)the development of switching program of power module;(2)the development of clock calibration program of clock module;(3)the development of filter program of signal processing module;(4)the development of driver and application program of control module;(5)the control program of host computer.(6)Development of data preprocessing program for PC.After completing the hardware development and software development work,a large number of indoor,flume and field tests were carried out,including:(1)indoor testing of the instrument's background noise,acquisition accuracy,dynamic range,power frequency suppression,power consumption and other technical indicators;(2)flume testing of the instrument's functionality;(3)field testing of field performance.The test results show that the background noise of the electric field channel of the instrument is between 0.53 and 0.68 UG Vrms,the power frequency suppression is 79 d B,the power consumption is between 7.4 W and 7.6 W under the working mode,the acquisition function of the instrument is relatively stable,the consistency between the instruments is good,the parameters meet the pre-designed targets,and the effectiveness and advancement of the instrument are verified.