Analysis of the Responses to Typical Electromagnetic Excitations in TD-AEM Systems

Analysis of the Responses to Typical Electromagnetic Excitations in TD-AEM Systems

Bing GuoYiming Zhang 

Faculty of Information Technology, Beijing University of Technology, Beijing 100124, China

Corresponding Author Email: 
guobing116633@163.com
Page: 
153-168
|
DOI: 
https://doi.org/10.18280/ama_a.540202
Received: 
1 May 2017
| |
Accepted: 
2 June 2017
| | Citation

OPEN ACCESS

Abstract: 

To help in the comparison of excitation sources for time-domain airborne electromagnetic (TD-AEM) systems, we develop an heuristic model of the response of the ground, represented by a conducting loop. For our comparison, our model includes the system waveforms. This model also includes a reception interval for on-time measurements, allowing the simulation and analysis of different electrical targets in both on-time and off-time. The results show that, for high-resistance targets, the use of the rectangular pulse excitation has the greatest response intensity during the off-time period, and for low-resistance targets, the use of the half-sine or the triangular pulse excitation has a higher signal-to-noise ratio during the on-time period. Results also show the influence of the pulse width on the response and may help in the selection of the pulse width while designing a survey.

Keywords: 

AEM, Excitation waveform, Free space loop coil model, Signal to noise ratio.

1. Introduction
2. Typical Excitation Response
3. Receiver Response Signal During Off-Time
4. Receiver Response Signal during On-Time
5. On-Time and Off-Time Full Response Comparison
6. Conclusions
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