Contrasting Techniques for Humanitarian Demining and Explosive Detection using Radiation Transmission and Backscatter: Development of a Low Cost Device based on Radiation Transmission
C. Murray Bartle, Chris Kröger and William Stephenson
GNS Science, Lower Hutt, New Zealand


Most common and emerging techniques for landmine detection focus on the detection of anomalies in the ground, without providing a definite indication that an explosive material is present. It is in material characterization that radiation-based techniques can play a vital role in mine detection [1]. Most detection systems under development are based on an adopted one-sided access only to the ground and this often limits material characterization due to the poor statistics of detected back- scattered or emitted radiation [2]. Whilst the one-sided approach ensures the ground (and threat material within it) is not disturbed, the resulting low detection sensitivity provide risks to the operator especially for hand held instrumentation. Attempts to improve the sensitivity of detection in an imposed one-sided geometry are expensive and require heavy and difficult-to-manoeuvre equipment. Such equipment may be too expensive for economic deployment in many countries.

We describe the design and use of prototype mine detector systems based on radiation transmission. Initial disturbance of the ground to deploy a radiation source can be a pre-assessed small area through which a radiation source and/or a detector is deployed beneath the ground surface.  Such deployments use methods employed in geophysical prospecting or in undertaking seismic surveys. Enhanced landmine and explosive material characterisation is possible through adopting dual beam transmission, imaging methods and algorithms used in industry. Scanning in a grid pattern can then progressively map out mine-free land. Such low cost methodology offers advantages in terms of locating landmines as distinct from clutter from non-threat objects.

[1] IAEA (1998) Detection of Explosives (in particular Landmines) by Low Cost Methods, IAEA/PS/AGM97-3, International Atomic Energy Agency, Vienna.

[2] C. Murray Bartle, C. Kröger, William Stephenson and John G West, Advances of industrial dual beam x-ray scanners and improved methods for detection of explosives and humanitarian de-mining. Proceedings of a Technical Meeting, Padova, Italy, 13-17, November 2006. IAEA-TM-29225.