A wideband (3 to 5 GHz) wide-scan connected array of dipoles with low cross polarization

A wideband, wide-scan prototype phased array of connected dipoles has been manufactured and tested from 3 to 5 GHz. The array comprises 7 × 7 elements, each fed by a loop-shaped transformer to avoid common-mode resonances. Such resonances typically affect this type of arrays, with consequent degradation of the polarization performance. The...

Early stage beneficial effects of cathodic protection in concrete structures

Over the last 25 years, cathodic protection (CP) of reinforced concrete structures suffering from chloride induced reinforcement corrosion has shown to be successful and durable. CP current causes steel polarisation, electrochemical reactions and ion transport in the concrete. CP systems are designed based on experience, which results in...

Optical characteristics of small surface targets, measured in the False Bay, South Africa; June 2007

During the False Bay trial (June 2007), the performance of a set of three optical sensors was tested against several small surface targets in a coastal area: a hyperspectral camera, a camera with a rotating polarization filter and a high resolution camera. One objective was the validation of a contrast and clutter model for the visual spectral...

Development and implementation of a camera system for faster area reduction

This paper describes the development and implementation of a low cost camera system that uses polarisation features of visible light for faster area reduction. The camera system will be mounted on a mechanical minefield area reduction asset, namely an AT mine roller of The HALO Trust. The automatic detection system will give an audible alarm in...

Landmine detection technology research in the Netherlands

This paper gives an overview of the activities on research and development in the technology area for landmine detection in the Netherlands. The main players, their projects and the long term and short term project goals are presented. The projects cover the range from military applications to humanitarian demining. In the "conventional"...

Surface mine signature modeling for passive polarimetric IR

A specular model has been used to predict the passive polarimetric infrared (IR) signature of surface-laid landmines. The signature depends on the temperature of the landmine and the sky radiance. The temperature of the landmine is measured using a thermocouple. The signature itself is measured using a polarimetric IR camera setup. The...

Usage of polarisation features of landmines for improved automatic detection

In this paper the landmine detection performance of an infrared and a visual light camera both equipped with a polarisation filter are compared with the detection performance of these cameras without polarisation filters. Sequences of images have been recorded with in front of these cameras a rotating polarisation filter. Due to optical...