Methods of Extracting early Desired Signal in the Transient Electromagnetic Field of Multiturn coil

摘要

Since early signal of transient electromagnetic field of multiple turn coil is influenced by itsrnmutual inductance, a blind area will be aroused in the detection of the transient electromagnetic method andrnthe shallow geological information will thus be lost. In this paper, through fitting the advanced signal inrnmeasured data of transient electromagnetic method with the methods of least square, polynomial andrnGaussian, a corresponding fitting equation is formulated so as to predict the early data, and thus the earlyrnsignals can be extracted. By calculating the theoretical model and setting the evaluation parameters, thisrnpaper proves that these methods are feasible, and by putting the above methods into practice, early signalsrnwhich correspond with the shallow geological information has been acquired. Therefore, the detection scopernof transient electromagnetic method is largely expanded.