Error assessment of microwave holography inversion for shallow buried objects

Holographic imaging is a technique that uses microwave energy to create a three-dimensional image of an object or scene. This technology has potential applications in land mine detection, as the long-wavelength microwave energy can penetrate the ground and create an image of hidden objects without the need for direct physical contact. However, the inversion algorithms commonly used to digitally reconstruct 3D images from holographic images, such as Convolution, Angular Spectrum, and Fresnel, are known to have limitations and can introduce errors in the reconstructed image. Despite these challenges, the use of holographic radar at around 2 GHz in combination with holographic imaging techniques for land mine detection allows to recover size and shape of buried objects. In this paper, we estimate the reconstruction error for the convolution algorithm based on hologram imaging simulation and assess these errors recommending an increase in the scanner area, considering the limitations that the system has and the expected error reduction.Comment: accepted at IWA-GP

Versatile Electronics for Microwave Holographic RADAR Based on Software Defined Radio Technology

The NATO SPS G-5014 project has shown the possibility of using a holographic RADAR for the detection of anti-personnel mines. To use the RADAR on a robotic scanning system, it must be portable, light, easily integrated with mechanical handling systems and configurable in its operating parameters for optimal performance on different terrains. The novel contribution is to use software programmable electronics to optimize performance and to use a time reference to obtain synchronization between the RADAR samples and the position in space, in order to make it easy to integrate the RADAR on robotic platforms. To achieve these goals we used the Analog Devices “ADALM Pluto” device based on Software Defined Radio technology and a time server. We have obtained a portable system, configurable via software in all its operating parameters and easily integrated on robotic scanning platforms. The paper will show experiments performed on a simulated minefield. The electronics project reported in this work makes holographic RADARs portable and easily reconfigurable, therefore adaptable to different applications from subsurface soil investigations to applications in the field of non-destructive testings