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In this paper, the disadvantages of using the Hough transform as a detector have been considered in a search radar. To illustrate the effect of these disadvantages on the performance of the detector, its performance has been compared with the optimum detectors. To do this, the Generalized Likelihood Ratio detector has been extracted for detecting a target line with unknown normal parameter pair in...
As we know, in the HRR RADARs we face range walking phenomenon, in fact, when a target moves during a CPI (Coherent Processing Interval), target returns from different scattering centers of the target produce different patterns in successive scans, this causes range walking. Therefore make the Performance of Conventional methods to maximize signal to noise ratio inefficient. Our solution for this...
The study is devoted to the representation of the millimeter-wave imaging technologies of tomography, ISAR, SAR, and Passive Radiometric Radar (PRR) in International Laboratory for High Technologies (ILHT) of TUBĐTAK-Marmara Research Center (MRC). Millimeter-wave measurement setups with their technical descriptions are introduced as well millimeter-wave reconstructed images obtained by the usage of...
In this paper, we present the main aspects of a novel method of inverse problem resolving based on the framework of Feynman's path integral evaluation for foreign object recognizing in clutter conditions. Results of the proposed theoretical approach are verified with the corresponding experiments carried out for infra-red (IR) imaging a small plastic tablet hidden inside various clothes near the human...
One of the main difficulties in Inverse Synthetic Aperture Radar imagery of a maneuvering target is the estimation of its motion parameters from the radar data. In this paper we show how the geometric features of a multistatic radar system can be used to obtain both translational and rotational motion with a multilateration approach. While many monostatic approaches in open literature attempt to estimate...
In this paper the structure of the track classifier based on the fussy logic is presented. The track classifier is a decision system, which allows determining whether the sequence of radar detections forming a track comes from the real target, or from other objects generating clutter. Human operator easily distinguishes the real tracks from the false ones; however the automaton of this process is...
Distinctive line of composite materials is indivisibility of their creation process and formation of properties from reception of ready details and knots. According to this, achievement of high reliability of products from composites it is necessary to improve, first of all, manufacturing techniques and to provide the control of observance of all parameters of technological process. Not less important...
A novel approach to ground moving targets classification by using information features contained in micro-Doppler radar signatures is presented. Suggested approach is based on using discrete cosine transform (DCT) coefficients extracted from radar signature as a classification feature and multilayer perceptron (MLP) as a classifier. Proposed pattern classification algorithm was tested by utilizing...
In this paper, the problem of retrieving the three-dimensional reconstruction of the ground scene observed by a Synthetic Aperture Radar System is addressed. To obtain such result, Multi-Pass systems are considered jointly with two recently proposed estimation techniques: the Compressive Sensing and the SAR Statistical Tomography.
Estimation of Q-factor of the open resonator by means of fractional-rational approximation of the reflection response has been considered. An advantage of the proposed technique in comparison with classical methods has been demonstrated. Dependence of Q-factor of the half-disk dielectric resonator and estimations of poles and zeros of resonance response against coupling coefficient value has been...
Solving Integral Equations with the Method of Moments has been a cornerstone in the field of computational electromagnetics for components and antennas in the microwave frequency range. In this invited paper, the applicability, advantages and disadvantages of this method are discussed in view of applying it at much higher frequencies, namely in the IR and optical frequency range. This invited presentation...
This paper concerns the author's research in progress. It is not a paper of a completed work. We have a principal example, nuclear norm optimization problem, which is described intuitively and formally. We believe that the proper formulation (and implementation) of r-algorithm based solution of the problem will have general applications and we are still seeking that formulation (and implementation)...
The design of an ultrabroadband 4 × 4 Butler matrix has been presented. The designed Butler matrix utilizes the previously developed 5-section coupled-line symmetrical 3-dB/90° directional coupler compensated with the use of several tuning capacitances as a basic element. The broadband 45° phase shifters have been realized with the use of a tandem connection of two the same couplers and two 2-section...
Research is dedicated to the questions of electromagnetic compatibility of isotropic point antennas which are set on the current-conductive body of arbitrary form (for example, airplane). Frequency-spatial division of real antennas of air vehicle must be predicted by previous calculations. It is expedient to make them on the stage of airplane constructing. This approach allows to get a corresponding...
Nonlinear microwave circuits are usually simulated with the harmonic-balance method, which is insensitive to the stability properties of the solution obtained. Therefore, this method must be complemented with stability-analysis techniques, in order to check the physical existence of the solution. Existing techniques assume a periodic excitation, usually consisting of a single tone. However, practical...
A new method for improvement of 2-D DOA estimation based on Matrix Pencil (MP) Method is presented. We show that with Tapering of the data matrix, the accuracy of azimuth and elevation estimation can be improved. The method directly applied to the algorithm and only with one snapshot of data, DOA can be estimated. The simulation results demonstrated the effectiveness of the proposed algorithm.
A new pseudo-noise resampling technique is proposed to mitigate the effect of outliers in Root-MUSIC. After resampling of Root-MUSIC via pseudo-randomly generated noise we combine it with conventional beamformer (as a result we obtain the resampled modified root-MUSIC). Censored selection of the results of pseudo-randomly resampled modified Root-MUSIC algorithms is exploited based on an appropriate...
Continuous monitoring of atmospheric opacity at 22 GHz and 36 GHz, ground meteorological parameters and atmosphere models allow separating absorption in water vapor, oxygen and hydrometeors and predicting atmospheric opacity at RATAN-600 radio telescope in wide band. Design, features and parameters of radiometric modules at 22 and 36 GHz for effective continuous monitoring of atmospheric opacity are...
The paper offers the simple calculating characteristics of a cavity filled with arbitrary temporary dispersive homogeneous isotropic medium and obtaining electromagnetic fields. The theoretical consideration is in the frame of Evolutionary Approach to Electromagnetics in Time Domain. The resonator filled with the complex dispersive medium excited by wideband current pulse is considered as an example.
This paper presents the radiation characteristics of a two-dimensional (2D) horn antenna structure for different multi-source feeding and back wall smoothing variations which are investigated parametrically. In order to get accurate and stable far-field results of the horn antenna in a fast way compare to the other 3D full-wave electromagnetic simulation programs available in the market, an attention...
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