基于LabVIEW的2^N伪随机信号在电法勘探中的应用  

Realization and Application of 2^N Pseudo-Random Signal Based on LabVIEW

作　　者：罗知亮 李志华[1] 朱翔野 沈茂丁[3] 徐华文[3] 

机构地区：[1]中国地质大学(武汉)自动化学院,湖北武汉430074 [2]吉林省长春市交通运输局,吉林长春130000 [3]中国石油天然气管道工程有限公司,河北廊坊065000

出　　处：《测控技术》2015年第5期16-18,22,共4页Measurement & Control Technology

基　　金：中国石油天然气管道工程有限公司项目(20142A01)

摘　　要：2^N序列伪随机信号的N个主频的振幅基本相等,应用在电法勘探中,可以实现一次供电、多频同时等精度测量,克服了传统方波需要多次单频测量耗时长、能量利用率低、不等精度的缺点,这对野外装备的轻便化、观测效率和可靠性以及提高数据的精确性都很有利。结合LabVIEW的简单直观的图形化编程、极大缩短程序开发周期、功能强大灵活的特点,2^N序列伪随机信号可以任意设置信号频率、主频个数。同时,2^N序列的游程编码传递给NI的数字输入模块,其输出波形作为发射机部分大功率H桥逆变电源的开关管的控制信号。考虑开关管的耐压能力,研究了在七频波每个直上直下的时刻加入不同延时对七频波频谱的影响,为逆变电路中器件的选型提供了依据。N-frequency amplitudes of 2^N sequence pseudo-random signal are substantially equality. In electrical prospecting, multi-frequency measurement equal accuracy can be achieved at the same time with only one power supply, which overcomes the shortcomings. It is favorable for portability of field equipment, observing efficiency and reliability as well as improving the accuracy of data. Combined with the features of LabVIEW of simple and intuitive graphical programming, powerful and flexible, the development cycle is greatly shorten, and 2＆N sequence pseudo-random signal can be set from signal frequency, frequency numbers. RLE of 2^N is passed to NI digital input module, the output waveform is used as the control signal of transmitter section H-bridge inverter power switch. Considering switching tube voltage capability, the direct process of adding different delays on each of seven frequency wave is studied on how to influence the seven-frequency wave spectrum, which is useful for the selection of the inverter circuit device.

关 键 词：伪随机信号 电法勘探 LABVIEW 游程编码 逆变电源 

分 类 号：TH763[机械工程—仪器科学与技术]