近地表电磁探测多频数字驱动信号产生技术  

Multi-frequency digital drive signal generation technology in near surface electromagnetic detection domain

作　　者：周逢道[1] 王金玉[1] 唐红忠[1] 张赫[1] 周继瑜[1] 

机构地区：[1]吉林大学地球信息探测仪器教育部重点实验室,长春130026

出　　处：《吉林大学学报（工学版）》2013年第3期682-687,共6页Journal of Jilin University:Engineering and Technology Edition

基　　金：国家潜在油气资源产学研用合作创新研究项目(OSR-02);吉林省科技发展计划重点项目(20100349)

摘　　要：针对近地表频率域电磁探测对发射信号的要求,以单极性倍频正弦脉宽调制技术(Si-nusoidal pulse width modulation,SPWM)为基础,利用现场可编程门阵列(Field-programma-ble gate array,FPGA)作为硬件平台,构建了基于嵌入式NiosII软核的片上系统SOPC(Sys-tem-on-a-programmable-chip);采用硬件描述语言(Verilog)实现多频SPWM的数字算法,产生频率间隔小、谐波失真(THD)低的多频数字驱动信号,克服了伪随机法频率间隔固定、系统结构复杂、位流法过分依赖负载线圈、算法复杂的缺点。最后,通过理论仿真和试验验证了本文方法的优越性。To meet the requirements of electromagnetic sounding for emission in the near-surface frequency domain, a System on a Programmable Chip （SOPC） was built using Field Programmable Gate Array （FPGA） as the hardware control platform. The SOPC was based on the unipolar and frequency multiplication Sinusoidal Pulse Width Modulation （SPWM）. Verilog was used to realize multi-frequency digital SPWM algorithm, generate the multi-frequency digital drive signal. This signal has a small frequency interval and low Total Harmonic Distortion （THD）. It can overcome the defects of other methods, such as the fixed frequency interval and complex system structure of pseudo random method, the over-dependence on load coil and complex algorithm of the bit-stream method. Theoretical simulation and experiment results verify the effectiveness of the method.

关 键 词：勘查技术 多频信号 单极性倍频正弦脉宽调制技术 可编程片上系统 谐波失真 

分 类 号：TH763[机械工程—仪器科学与技术]