等值反磁通瞬变电磁法天线零磁通面位置的确定方法  

A method for determining the position of zero magnetic flux plane of antennae using the opposing-coils transient electromagnetic method

作　　者：亓庆新 席振铢[2] 徐昱 木仁 QI Qing-Xin;XI Zhen-Zhu;XU Yu;MU Ren(Hunan Wuwei Geological Technology Co.,Ltd.,Changsha 410205,China;School of Geosciences and Info-Physics,Central South University,Changsha 410083,China;Hunan Institute of Metrology and Test,Changsha 410014,China)

机构地区：[1]湖南五维地质科技有限公司,湖南长沙410205 [2]中南大学地球科学与信息物理学院,湖南长沙410083 [3]湖南省计量检测研究院,湖南长沙410014

出　　处：《物探与化探》2022年第6期1540-1544,共5页Geophysical and Geochemical Exploration

基　　金：湖南省标准化专项“等值反磁通瞬变电磁法通用技术标准”(2011709)。

摘　　要：确定零磁通面几何位置是等值反磁通瞬变电磁法探测系统的关键。为此,提出了一种调零方法:用等值反磁通瞬变电磁仪连续发送固定频率的双极性方波,接收机实时采集接收天线的时间域信号,并使用离散傅里叶变换分别计算出粗调、细调和微调接收天线位置的最小功率谱密度(A1、A2、A3),当A1>A2>A3时,接收天线处于零磁通面。发送20 kHz双极性方波试验的结果表明,当A1>A2>A3时,二次场衰减信号过渡过程得到明显改善。该方法可为高性能等值反磁通瞬变电磁仪器的设计和制造提供参考。Determining the geometric position of the zero magnetic flux plane is the key to the detection system of the opposing-coils transient electromagnetic method(opposing-coils TEM).Given this,a zeroing method was proposed in this study.First,an opposing-coils transient electromagnetometer was used to continuously send the bipolar square wave of fixed frequency.Then,the receiver collected the time domain signals of the receiving antenna in real time,and the discrete Fourier transform was used to calculate the minimum power spectral density(A1,A2 and A3)at the roughly-,finely-,and micro-tuned receiving antenna positions.When A1>A2>A3,the receiving antenna was in the zero magnetic flux plane.Finally,the test results of transmitting 20 kHz bipolar square wave showed that the transition process of the attenuation signals of the secondary field can be significantly improved under the condition of A1>A2>A3.

关 键 词：等值反磁通 瞬变电磁 零磁通面 功率谱密度 

分 类 号：P631[天文地球—地质矿产勘探]