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This work deals with a comparison between multi-beam leaky-wave and slotted waveguide pillbox antennas. The antenna systems present the same pillbox architecture: feeding part, quasi-optical system and radiating part. Two different radiating parts are considered: a leaky-wave solution and an array of slotted waveguides. In particular, an array of slots etched on the uppermost metal layer of the pillbox...
For the first time in the world airborne Frequency Modulated Continuous Wave (FMCW) Synthetic Aperture Radar (SAR) images have been acquired in interferometric mode. The paper reports on the X-band images collected by the new high resolution, compact MetaSensing interferometric SAR sensors in 2009. MetaSensing approach allows cost-effective SAR mapping by employing small, readily available Cessna...
The inter-channel isolation of an FMCW radar with interleaved transmit-receive array antennas is, for the first time, characterized by measurements on an operative system. Theoretical predictions, based on full-wave simulations, are compared to computations from the measured antenna scattering parameters. In both cases, the received signals are re-combined by using ideal equi-phase and equi-amplitude...
In this paper, results of comparative study of several designs of tapered-slot antennas for subsurface applications are presented. To this end, influence of mutual arrangement of the antennas in bi-static configuration and placed in the antenna arrays has been studied using both simulations and experiments. Major attention is paid to the behaviour of the transmitting-receiving antenna pair near the...
The research field of MIMO radar offers a bunch of new opportunities for various applications. Imaging MIMO radars can be used as a significant supplement to usual SAR and phased array radars and can extend the common applications for radar. MIRA-CLE X is an X-band MIMO radar consisting of 16 transmit and 14 receive antennas. During signal processing, 224 virtual antenna elements are generated to...
In this paper, we present through the wall (TTW) radar detection simulations with an emerging radar architecture which is the multiple-input multiple-output (MIMO) radar. The urban environment, especially in TTW detection, is very tough for radar detection. With the aim of improving the detection performances, we use several spaced antennas in transmission which gives a spatial diversity leading to...
Based on the legacy of marine radars, historical coastal surveillance sensors were based on the cheap magnetron-slotted waveguide antenna combination and were addressing sea-lane traffic control missions. New regulations in the marine world, such as the SOLAS convention, and increasing requirements for very small objects tracking, put new requirements on radar performance. It triggered an evolution...
We develop a new geometric approach for radar target detection which is based on the notion of Riemannian median and the information geometry of covariance matrices. First of all, we give the definition of Riemannian median and a simple algorithm to compute it. After that, the explicit expressions of reflection coefficients parametrization of covariance matrices are obtained, with which the Riemannian...
This contribution gives an overview of civil state-of-the-art and also some novel applications of radar sensors in the millimeter-wave frequency range, together with some general principles and a number of examples of such radar systems.
The extraction of accurate transistor models is essential for a reliable and efficient design of transmit/receive modules, which in turn is a keystone for the development of active electronically scanned array radars. The present paper is aimed at analysing the implementation of non-quasi-static effects for advanced millimeter-wave FET models. The non-quasi-static phenomena can be neglected at few...
This paper presents the results of FOD measurements conducted using a broadband 78 GHz radar sensor. Previous studies with a short-range setup up to 30 m showed promising results. However, to meet the requirements of the intended application, the range has to be increased significantly. As for all radar systems, the range can be extended by increasing the transmitted power and/or the antenna gain...
In this paper, problem of efficient representation of large database of target radar cross section is investigated in order to minimize memory requirements and recognition search time, using a tree structured hierarchical wavelet representation. Synthetic RCS of large aircrafts, in the HF-VHF bands, are used as experimental data. Hierarchical trees are built using wavelet multiresolution representation...
Up to now, combat aircrafts are fitted with Fire Control Radar (FCR), Electronic Warfare System (EWS), and radio links. Each of these systems is dedicated to a particular task and the cooperation is reduced to a minimal exchange of information between them, so far. Major system performance enhancements are to be expected from close co-operations to each other sensors. The future co-operations can...
This paper describes a new type of sounding signals for polarimetric FMCW radar and the corresponding signal processing technique. The inter-period compensation (IPC) algorithm is proposed for isolation increase in radar channels. The novelty concerns the use of orthogonal polarizations of two bi-cyclic LFM-signals having an additional phase shift every second sweep. Summation units proposed for use...
Direct numerical simulations are used to calculate wide-band HF radar backscatter from evolving ocean-like surfaces in 2-D space. With the attainable spatial resolution of about 15 m, the large-scale wave pattern is visible in range-time plots of backscatter magnitude. The double Fourier transform of the signal magnitude or power in range and time reveals strong harmonics located along the dispersion...
The paper presents a design procedure for a multistatic passive radar system, that aims at its performance optimization, in terms of 3D positioning accuracy. Specifically, the proposed procedure considers the main features of the considered air traffic control scenario and the main physical and geometrical features of the passive radar receivers and guides the designer to select the geometry that...
In this paper we propose a photonic technique for a reconfigurable microwave signal generation based on the beating in a photodiode of two laser modes from a regenerative Fiber Mode-Locked Laser (FMLL). The excellent performance of this kind of pulsed laser guarantees high stability to the generated microwave signal even at ultra high frequencies (up to W band). Therefore, by using the proposed architecture,...
This paper addresses adaptive detection and tracking of a point-like target in thermal noise plus clutter which is assumed to be heterogeneous from one range cell to another. To this end, a track-before-detect scheme is derived and assessed; its design relies on autoregressive modeling of noise returns. A preliminary performance assessment, based upon Monte Carlo simulation, shows that it can outperform...
In order to lower the cost of basic MMIC components and modules for commercial and civilian phased array applications dramatic cost reductions when compared to the present military must be realized. These cost reductions can only be achieved by employing highly integrated RFICs which are produced on high volume process lines for low cost using GaAs MMICs and Silicon based technologies where appropriate,...
In this paper a multi-model track-before-detect (MM-TBD) is proposed for the HF Over-The-Horizon-Radar (OTHR) manoeuvring target detection. Multiple hypotheses about target manoeuvres and echo sources are represented in the multi-model-estimation framework with each sub-filter corresponding to one hypothesis. The track output of each sub-filter is obtained based on the maximum likelihood criterion...
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