KEYWORDS: Land mines, Imaging systems, Signal to noise ratio, Extremely high frequency, Principal component analysis, Metals, Millimeter wave imaging, Aluminum, Reflection, Mining
With over 110 million landmines buried throughout the world, the ability to detect and identify objects beneath the soil is crucial. The increased use of plastic landmines requires the detection technology to be able to locate both metallic and non-metallic targets. A novel active mmW scanning imaging system was developed for this purpose. It is a hyperspectral system that collects images at different mmW frequencies from 90-140 GHz using a vector network analyzer collecting backscattering mmW radiation from the buried sample. A multivariate statistical method, Principal Components Analysis, is applied to extract useful information from these images. This method is applied to images of different objects and experimental conditions.
Transmission spectra were measured over the range 90-4200 GHz for a locally sourced soil sample composed mostly of quartz sand with ~200 micron particle size. A vector network analyzer covered the spectral range 90-140 GHz. A Fourier spectrometer collected transmission spectra over the range 120 to 4200 GHz. Transmission drops to zero for wavelengths shorter than the characteristic particle size of the sample as a consequence of scattering. Transmission spectra were also measured for various liquids in the 90-140 GHz and 450-1650 GHz ranges in the interest of index matching. These liquids were mixed with the soil sample and were found to reduce scattering and increase transmission through the soil at higher frequencies. This work is relevant to mine detection using THz and millimeter wave (mmW) radiation.
Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks.
You are receiving this notice because your organization may not have SPIE eBooks access.*
*Shibboleth/Open Athens users─please
sign in
to access your institution's subscriptions.
To obtain this item, you may purchase the complete book in print or electronic format on
SPIE.org.
INSTITUTIONAL Select your institution to access the SPIE Digital Library.
PERSONAL Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.