Results of a high-resolution airborne TEM system demonstration for unexploded ordnance detection

Airborne geophysical sensor systems using boom-mounted configurations now play an important role in characterizing ordnance-contaminated defense sites. Most of the systems developed to date have been magnetometer systems. These have proven ineffective at sites where basalt or other magnetic geologic units or soils have caused unacceptable noise in the data. Electromagnetic (EM) systems have been developed as an alternative to magnetometer systems for such sites. Recent evaluation of New Mexico field results from the new TEM-8 time-domain EM system has shown successful detection of emplaced blind-seeded ordnance items. Overall, 109 of 110 items were detected, some as small as [Formula: see text] mortars at an area with moderately magnetic geology. The TEM-8 system was also effective in mapping ordnance at a bombing target with severe geologic interference due to basalt, where a previous airborne magnetometer survey proved ineffective. Data and performance metrics for both survey areas are presented and evaluated.

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Field tests of an experimental helicopter time‐domain electromagnetic system for unexploded ordnance detection

Geophysics ◽

10.1190/1.1759452 ◽

2004 ◽

Vol 69 (3) ◽

pp. 664-673 ◽

Cited By ~ 11

Author(s):

Les P. Beard ◽

William E. Doll ◽

J. Scott Holladay ◽

T. Jeffrey Gamey ◽

James L.C. Lee ◽

...

Keyword(s):

Time Domain ◽

Eddy Currents ◽

Field Tests ◽

Field Trials ◽

Unexploded Ordnance ◽

Signal Attenuation ◽

Signal To Noise ◽

Electromagnetic System ◽

Time Domain Electromagnetic ◽

Unexploded Ordnance Detection

Field trials of a low‐flying time‐domain helicopter electromagnetic system designed for detection of unexploded ordnance have yielded positive and encouraging results. The system is able to detect ordnance as small as 60‐mm rounds at 1‐m sensor height. We examined several transmitter and receiver configurations. Small loop receivers gave superior signal‐to‐noise ratios in comparison to larger receiver loops at low heights. Base frequencies of 90 Hz and 270 Hz were less affected than other base frequencies by noise produced by proximity to the helicopter and by vibration of the support structure. For small ordnance, a two‐lobed, antisymmetric transmitter loop geometry produced a modest signal‐to‐noise enhancement compared with a large single rectangular loop, presumably because the antisymmetric transmitter produces smaller eddy currents in the helicopter body, thereby reducing this source of noise. In most cases, differencing of vertically offset receivers did not substantially improve signal‐to‐noise ratios at very low sensor altitudes. Signal attenuation from transmitter to target and from target to receiver causes signals from smaller ordnance to quickly become indistinguishable from geological background variations, so that above a sensor height of about 3 m only large ordnance items (e.g., bombs and large caliber artillery rounds) were consistently detected.

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ENHANCEMENT OF SPATIAL RESOLUTION OF THE LROC WIDE ANGLE CAMERA IMAGES

ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences ◽

10.5194/isprs-archives-xli-b7-685-2016 ◽

2016 ◽

Vol XLI-B7 ◽

pp. 685-692

Author(s):

P. Mahanti ◽

M. S. Robinson ◽

H. Sato ◽

A. Awumah ◽

M. Henriksen

Keyword(s):

High Resolution ◽

Image Fusion ◽

Work Performance ◽

Performance Metrics ◽

Resolution Enhancement ◽

Image Data ◽

Band Ratio ◽

New Science ◽

And Performance ◽

Wide Angle Camera

Image fusion, a popular method for resolution enhancement in Earth-based remote sensing studies involves the integration of geometric (sharpness) detail of a high-resolution panchromatic (Pan) image and the spectral information of a lower resolution multi-spectral (MS) image. Image fusion with planetary images is not as widespread as with terrestrial studies, although successful application of image fusion can lead to the generation of higher resolution MS image data. A comprehensive comparison of six image fusion algorithms in the context of lunar images is presented in this work. Performance of these algorithms is compared by visual inspection of the high-resolution multi-spectral products, derived products such as band-to-band ratio and composite images, and performance metrics with an emphasis on spectral content preservation. Enhanced MS images of the lunar surface can enable new science and maximize the science return for current and future missions.

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