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AbstractThe condition for maximum power transfer of 2-coils wireless power transfer (WPT) system is derived from circuit analysis and discussed together with the respective WPT system efficiency (η). In the sequence, it...

Abstract Recently, many machine learning techniques have been presented to detect brain lesions or determine brain lesion types using microwave data. However, there are limited studies analyzing the location of the lesio...

Abstract This article discusses procedures for production of tapered fibers in different diameters (tapers) and Bragg gratings writing (tFBG) in such fibers. The reflection spectra in different tFBGs are compared with a ...

Abstract This paper reports detailed propagation analyses of mm-wave indoor networks based numerical simulations of the wireless coverage and measurements of the propagation coefficient at 28 and 38 GHz. Additionally, ma...

An optimized design for the spanner shape regular hexagonal monopole (RHM) patch antennas has been reported to yield ultra wide band (UWB) impedance bandwidth. Impedance and radiation characteristics are presented and di...

Abstract Microwave irradiations from vegetation canopy are strongly influenced by its dielectric properties and give useful information for microwave remote sensing -interpretation and applications. This paper reports on...

Abstract— A coplanar waveguide (CPW)-fed patch antenna with triple wideband is presented for simultaneously satisfying Wireless Local Area Network (WLAN) and Worldwide Interoperability for Microwave Access (WiMAX) appl...

Self-affine property of a modified multifractal Cantor geometry is exploited to design frequency selective surfaces (FSS) with multiband response. The main advantage of the proposed structure is to design multiband FSS w...

Abstract In this paper, a finite-difference time-domain (FDTD) formulation, based on the exponential matrix and on thin material sheet methods is developed for modeling subcellular thin graphene sheets. This formulation ...

A comparative analysis of two cylindrical complex-frequency-shifted perfectly matched layers (CFS-PML) absorbing boundary condition (ABC) for bi-dimensional (2-D) finite-volume (FV) simulations in the frequency domain is...

Abstract WDM-PON has been considered a promising solution for future fronthaul links concerning new mobile networks applications. However, in order to avoid inventory problems and reduce operation costs, there is a need ...

In this paper, we present a comparison between OFDM and STDCC sounding techniques used to wide band channel characterization in suburban environments at 3.5 GHz band. Measurements of the received signal's power delay pro...

Abstract We report the implementation of an optical-wireless 5G network based on generalized frequency division multiplexing (GFDM) and multi-Gbit/s communication. Dual-drive Mach-Zehnder modulator was employed, enabling...

Abstract Irregular terrains covered with forest vegetation represent a challenging scenario for radio planning. A case of particular interest is the one where a forest-covered high hill or mountain is interposed to the l...

Abstract In this paper, it is presented a general optimization methodology for improving empirical models predicting Okumura-Hata, Cost-231, ECC-33, and Egli using Genetic and Differential Evolution Algorithms. The metho...

Abstract A methodology based on spectral analysis for localization of multiple partial discharges in dielectric region of hydro-generator coils is proposed. This pinpointing of multiple discharges aims to provide means f...

AbstractA compact (20 x 20 mm2 size), coplanar waveguide (CPW) fed, octagonal slotted, dual-band antenna is presented in this paper. The proposed antenna has a simple structure consisting of an octagonal slot, L-shape st...

Abstract This paper describes an investigation of the possibility of using a new conductive ink, insted of copper clad laminates, in the manufacturing of microstrip patch antennas on glass and fiberglass substrates and o...

Abstract In this paper a 2-4 GHz microstrip IFM (Instantaneous Frequency Measurement) subsystem that uses Wilkinson power dividers, frequency discriminators based on band-stop filters and a DC arduino section is reported...

Abstract This paper presents the optimization performance of non-uniform linear antenna array with optimized inter-element spacing and excitation amplitude using Particle Swarm Optimization (PSO). The aim of the proposed...

Abstract The rapid development of the Fifth Generation (5G) networks encourages researchers to improve the Radio over Fiber (RoF) technique to achieve data rates of 10 Gbps and beyond. That led to a significant increase ...

Abstract In this paper we have presented the four new investigations using different structures of Photonic Crystal Fiber (PCF) for broadband communication applications and narrows down on the design which can provide la...

The use of wireless local area networks, called WLANs, as well as the proliferation of the use of multimedia applications have grown rapidly in recent years. Some factors affect the quality of service (QoS) received by t...

Abstract This paper describes a method using Quantum Particle Swarm Optimization to obtain a broadband frequency invariant pattern for synthesis of nonuniformly spaced linear array of isotropic antennas. Two cases relate...