This paper presents a novel system to obtain images from the underground based on ground penetrating radar (GPR). The proposed is composed by module mounted board an unmanned aerial vehicle (UAV), which allows safe inspection of difficult-to-access areas without being in direct contact with soil. Therefore, it can be used detect dangerous buried objects, such as landmines. measurements are coherently combined using synthetic aperture (SAR) algorithm, requires cm-level accuracy positioning...

This paper presents a compact, low-cost unmanned aerial system for antenna measurement. The proposed overcomes existing limitations in terms of vehicle positioning and data geo-referring accuracy using real-time kinematic to achieve centimeter-level accuracy. Amplitude-only measurements acquired power sensor are processed by means the phaseless sources reconstruction method. is an iterative phase retrieval technique that allows recovering equivalent currents distribution, which characterizes...

This work presents an enhanced autonomous airborne Synthetic Aperture Radar (SAR) imaging system able to provide full 3D radar images from the subsurface. The proposed prototype and methodology allow safe detection of both metallic non-metallic buried targets even in difficult-to-access scenarios without interacting with ground. Thus, they are particularly suitable for detecting dangerous targets, such as landmines Improvised Explosive Devices (IEDs). is mainly composed by Ultra-Wide-Band...

An improved Ground Penetrating Radar (GPR) system on board an Unmanned Aerial Vehicle (UAV) is presented in this contribution. The has been designed for the detection and imaging of buried targets and, particular, landmines Improvised Explosive Devices (IEDs). Resting hardware architecture a previous aerial platform, proposed scanning area increased capabilities are improved. These improvements achieved by employing two receiving antennas new processing techniques that increase...

The usage of unmanned aerial vehicles (UAVs)-based ground penetrating radar (GPR) systems has gained interest over the last years thanks to advantages ground-based systems, such as contactless inspection and capability, reach difficult-to-access areas. former is paramount importance concerning detection buried threats, improvised explosive devices (IEDs) landmines. Current state-of-the-art UAV-based GPR are able provide centimeter-level resolution use GPR-synthetic aperture (SAR) processing...

In recent years there has been an increasing research interest in the development of airborne-based Ground Penetrating Radar (GPR) systems for safe and fast detection buried threats such as landmines Improvised Explosive Devices (IEDs). Compared to other sensors metal detectors or magnetometers, GPR is able detect either metallic non-metallic targets. Besides, use Ultra Wide Band (UWB) radiofrequency hardware allows retrieving high resolution images subsoil, thus improving capabilities....

This work aims to simplify the characterization process of coded-apertures for computational imaging (CI) at microwave frequencies. A major benefit presented technique is minimization processing time needed calculate system sensing matrix CI-based compressive applications. To achieve this, a deep learning-based approach proposed which capable generating using features learned directly from coded-aperture distribution. avoid vanishing gradient problem, learning network contains skip...

Recent advancements in wave computing using metasurfaces are poised to transform wireless communications by enabling high-speed, energy-efficient, and highly parallelized signal processing. These capabilities essential meet the ultra-high data rates of up 1 terabit per second minimal latency as low millisecond required next-generation networks. Diverging from traditional digital processing, adopts continuous analog signals foster innovative functions such over-the-air computation, integrated...

This paper introduces three methodologies to improve synthetic aperture radar (SAR)-based techniques used in ground-penetrating (GPR) systems. They consist of: 1) equalization of the frequency response transmitting (Tx) and receiving (Rx) antennas; 2) processing SAR images using partially overlapped subbands; 3) imaging domain clustering. The goal is combine ground penetration capabilities lower bands with resolution achieved when increasing overall band, resulting enhanced detection...

A two-dimensional (2D) dynamically reconfigurable metasurface aperture is presented to perform frequency selective through wall imaging (TWI) with an unknown structure of the wall. Generally, in TWI, medium properties and thickness need be known advance, which not always possible. Moreover, compensating for these effects can significantly increase computational complexity. We propose a two-stage method that leverages concept antenna (DMA) narrow band are minimum TWI. First, two simple probe...

The capability of in-situ antenna measurement and diagnostics using a compact low-cost unmanned aerial system is presented. An onboard power sensor collects amplitude-only measurements, which are processed by means an iterative phase retrieval technique. This technique allows recovering equivalent currents distribution, characterizes the under test (AUT). These can be used for as well to evaluate field radiated AUT. In mobile networks, proposed interest rapid assessment antenna's operational...

In this paper, the challenge of enhancing efficiency computational imaging (CI) at microwave frequencies is addressed.While CI simplifies hardware complexity conventional techniques, it requires knowledge a sensing matrix that governed by aperture radiated fields.This can be computationally expensive process.As drastic alternative to approach, Pix2pix conditional generative adversarial network (cGAN) introduced learn intricate relationship between back-scattered measurements from scene and...

A conventional synthetic aperture radar (SAR)-based technique for soil permittivity estimation is presented in this contribution. Ground penetrating imaging techniques are mainly based on SAR algorithms that take into account the wave velocity accurate of buried objects. Reflectometers, datasheets, and indirect observation methods commonly considered characterization. However, factors such as humidity temperature may cause some variations constitutive parameters. This contribution proposes a...

This work proposes a novel Ground Penetrating Radar (GPR) system to detect landmines and Improvised Explosive Devices (IEDs). The system, which was numerically evaluated, is composed of transmitter placed on vehicle looking forward receiver mounted drone downwards. combination offers both good penetration high resolution, enabling the detection non-metallic targets mitigating clutter at air–soil interface. First, fast ray tracing simulator developed find proper configurations system. Then,...

Airborne-based Ground Penetrating Radar (GPR) systems have proved to be an efficient solution for safe and accurate detection of buried threats such as Improvised Explosive Devices (IEDs) anti-personnel anti-tank landmines. The design these prototypes is influenced by several parameters the working frequency band or maximum weight size payload placed on board Unmanned Aerial Vehicle (UAV). In this sense, one main bottlenecks found in proper selection GPR antenna. This contribution focuses...

Dynamic metasurface antennas (DMAs) have recently been introduced as a computational imaging (CI) platform that offers significant advantages over conventional systems. Such are able to produce tailored radiation patterns later used encode the scene's information into few measurements. However, since signal is compressed, image reconstruction in frequency domain using range migration algorithm (RMA) cannot be directly applied CI-based apertures synthesized with DMAs. More sophisticated...

This paper proposes a deep learning-based motion deblurring method for radar images using point-spread function (PSF) estimations. Motion blur is common problem in imaging due to the movement of platform or target. The proposed uses convolutional neural network (CNN) learn mapping between blurred and sharp images. In addition, PSF estimated separate CNN. point spread utilized conjunction with input image reconstruct deblurred image. reconstruction process further optimized by incorporating...

Ground Penetrating Radar (GPR) systems on board Unmanned Aerial Vehicles (UAVs) have been successfully used for subsurface imaging applications. Their capability to detect buried targets avoiding the contact with soil turn these into a great solution threats, such as landmines and Improvised Explosive Devices (IEDs). Significant advances also conducted enhance detection capabilities of systems, complementing Synthetic Aperture (SAR) processing methods several clutter mitigation techniques....

A near-field (NF) measurement method stemming from the microwave computational imaging (MCI) concept is proposed in this letter.In an MCI system, sensing matrix comprises radiated fields of both transmitter and receiver.We demonstrate that, with apriori knowledge antenna radiating quasi-random patterns tailored for MCI, allows calculation NF distribution antenna-under-test (AUT).The technique follows a twostep process.First, system fixed calibration targets directly predicted backscattered...

An inverse method and measurement setup for profile constitutive parameters reconstruction from monochromatic phaseless information is presented. The based on the minimization of a cost function that relates measured field with one scattered by model object under test (OUT), where position, contour, are unknowns. As result, directly related to problem unknowns, thus avoiding need an intermediate phase retrieval step. Due nonlinear nature function, global optimization techniques, such as...

In recent years, Unmanned Aerial Vehicles (UAV)-based Ground Penetrating Radar (GPR) systems have been developed due to their advantages for safe and fast detection of Improvised Explosive Devices (IEDs) landmines. The complexity these requires performing extensive measurement campaigns in order test performance capabilities. However, UAV flights are limited by weather conditions battery autonomy. To overcome problems, this contribution presents a portable easily-deployable setup which can...