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A design and simulation of a smart UWB antenna applicable in radars systems is reported in this research. The proposed configuration consists of monopole UWB antenna printed on FR-4 low-cost substrate with dimensions of 35 × 35 mm2. The present UWB antenna performs in the frequency spectrum 3.1–10.6 GHz. Through reconfiguration, the antenna has the ability to intelligently manage the problem of the...
In this paper, we propose a novel metaheuristic efficient approach based on hybridization of tabu search algorithm (TS) and local search algorithm (LS) for multiuser detection (MUD) in an uplink Space Division Multiple Access Orthogonal Frequency Division Multiplexing (SDMA-OFDM) communication system. This technique is used to improve the performance limitation of the conventional detectors caused...
This paper proposes patch antenna for X-band [8.2 GHz; 12.4 GHz] and military applications, enhanced by double negative metamaterial complementary (C-DNM) cells. Two different structures will be presented and discussed, which involve: (1) C-DNM with square patch antenna, and (2) C-DNM with circular patch antenna. The antenna was designed with resonance frequency around at 12 GHz. The metamaterial...
A modified rectangular metallic ring Frequency Selective Surface (FSS) with single layer for multiband applications is proposed in this article. By using the wave concept iterative process method WCIP, the resonant characteristics of the proposed FSS are derived. This structure is sensitive to polarization of the incident wave. The proposed FSSs elements are composed by development of a basic rectangular...
In this paper, we address the problem of target detection in a spatially correlated Lognormal clutter when no prior information is available about the presence or not of any clutter edge and/or interferences in the reference window. We propose a detector based on censoring and detection algorithms with constant false censoring and alarm rates (CFCAR). The CFCAR property is guaranteed by use of linear...
In this paper, hybrid algorithm called gradient particle swarm optimization (GPSO) is proposed for training artificial neural networks (ANN). Then, the trained networks are applied to modeling waveguide filters (broad-band e-plane filters with improved stop-band and rectangular waveguide h-plane three-cavity filter). For validate effectiveness of this algorithm, we compared the results of convergence...
This paper proposes an improved approach for the design and realization of a compact microstrip Wilkinson power divider in the UHF frequency band. The circuit is simulated using dimensions obtained from the Wilkinson power divider theory but realizations based on these dimensions presented a shift in the frequency band of operation. To account for this frequency shift in the design phase, an approach...
This paper comprise a novel multiple input multiple output (MIMO) antenna with very compact size of 16×10 mm2. The proposed MIMO antenna contains two opposite facing half cylindrical dielectric resonator antenna (HCDRA) elements excited from two Sub-Miniature version A (SMA) connectors with a characteristic impedance of 50 ohm. The position of coaxial probe is optimized for the first time to enhance...
Direction finding (DF) system employing phase interferometer of long baselines provides high accuracy of Angle Of Arrival (AOA), however, it also implicates phase ambiguity and phase error. The main contribution of this paper involves two parts. The first one concerns the performance comparison of three algorithms applied for determination of unambiguous AOA using simulations. These algorithms are...
In this paper, we present a design of a beamforming pattern antenna based on the Butler matrix. The study has two component related to the design of the Butler matrix operating in the UWB spectrum (from 3.1 up to 10.6 GHz). The Butler matrix with monolayer it often have a very narrow band, as well a very large size. To overcome these problems, we present in this work the designing of an ultra-wideband...
The paper proposes a compact UWB (Ultra Wide Band) antenna with five band notched covering the frequency range from 2.5 GHz to 11.58 GHz with VSWR (voltage standing wave ratio) less than 2. The proposed antenna has a size of 30×30 mm2. To achieve the rejected band, five slots are inserted in the radiating element and the feed-line including the WiMAX (3.2– 3.6 GHz), C-band (3.8–4.2 GHz and 5.725–7...
This paper deals with the protection of the exchanged data between a drone and mobile stations against blind interceptions. The developed strategy for a Single-Input Multiple-Output Orthogonal Frequency Division Multiplexing (SIMO-OFDM) communication system consists to prevent the interceptors to achieve a good blind channel estimation while allowing an accurate channel identification by the drone...
The co-centered orthogonal loop and dipole array is commonly used in sources localization using jointly the polarization and spatial diversities. For this type of array, most of the performance analysis studies present in the literature rely on asymptotic regimes. In this paper, we focus on the performance analysis in the non-asymptotic region. More precisely, we derive the McAulay-Hofstetter bound...
A simple pattern reconfiguration approach of an Ultra Wide Band (UWB) monopole antenna is presented. By inserting a VIVALDI shape in the Coplanar-Waveguide (CPW) ground plane, the pattern reconfiguration is achieved without changing the original size and form of the monopole. Only two switches were used, thus the main beam is controlled depending on the state of these switches. Therefore, in the band...
Tracking a target in a Cartesian repair with polar radar measurements usually involves transformation of the measurements from a polar coordinate frame to a Cartesian coordinate one. In a large cross-range target tracking, the classical conversion method becomes inconsistent and is therefore inadequate. In this paper we propose a new decoupled tracking filter that uses Unbiased Converted Measurements...
his paper presents a new efficient track-to-track fusion (T2TF) algorithm based on the Information Filter (IF) framework which takes into account phenomena encountered in practical applications. In fact, it combines a modified version of the IF framework and a self-tuning fusion procedure based on likelihood functions to address issues such as the correlation of the estimates, the transmission shortcomings...
Snapshot based rollback recovery is one of the widely used techniques for applications such as scientific computing, database, telecommunication and critical mission applications. The goal of this paper is to design and implement a snapshot security protocol, which calculates consistent global snapshot for distributed applications running on radar networks in order to add more reliability and high...
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