频分多址法用于硐室盲炮检测与识别的试验

为探明硐室爆破中的盲炮,在高精度磁法、瞬变电磁法和瞬态电磁耦合法的研究基础上研究开发了频分多址法。该法是利用电磁波在大地中的传播规律,在不同装药硐室中预置发射不同频率的电磁信号发生器,在地面安装无线检测接收系统,通过接收到的不同频率信号来实现硐室盲炮检测与识别。试验结果表明,电场信号信噪比低、反应微弱,磁场信号的信噪比高,采用频率在1000Hz左右的磁场信号作为检测的信号源的实用性更好;频分多址法可以检测与识别出地下225m的盲炮,能满足地下硐室盲炮检测的距离要求;检测精度可达到2Hz,能同时有效地检测与识别地下单个及多个盲炮的存在。

STUDY ON DETECTION AND IDENTIFICATION OF MISFIRE IN CHAMBER BLASTING BY FREQUENCY DIVISION MULTIPLE ACCESS METHOD

In order to proved the misfire in the chamber blasting,the method of frequency divison multiple access was carried on the theoretical feasibility analysis and experimental demonstration on the basis of high-precision magnetic method,transient electromagnetic method and transient electromagnetic coupling method.At first,presenting the signal generator which can send different signals in different chambers,installing a wireless receiving inspection system on the ground.Then the propagation rules of electromagnetic wave in the earth was used,compared with the difference electromagnetic field difference before and after.At last,achieving the objective of detection and identification of misfire in chamber blasting by identifying the different frequency electromagnetic signal.The experiment showed that electric signal and magnetic signal could be used as a detection signal,but the signal to noise ratio was high and the response was weak of the electric signal.In actual application,the magnetic signal as the detection signal should be chosen.Frequency divison multiple access method could detect 225 m underground misfire which can satisfy the demands of detection distance.Precision could be up to 2Hz.Frequency divison multiple access method can effectively detect and identify the single or multiple misfire at the same time.