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In this paper we propose a ray-tracing method for modeling the correlation of the received signals by two or more antennas operating in a multipath environment. Assuming that the maximum excess delay in the channel is known, we create an elliptical region surrounding both the transmitter and receiver antennas. A number of scatterers are randomly distributed(More)
Swarm Optimization (PSO) is a powerful evolutionary computation technique for solving continuous-valued optimization problems in various fields of engineering. However, its binary version could not attract much attention such that research on the discrete form of the PSO is currently not massive. In this paper, the Boolean PSO is introduced based on the(More)
—A novel dual-frequency dual-linear-polarization printed antenna element benefiting from a single-feed single-layer structure is introduced in this paper. The Boolean particle swarm optimization algorithm in conjunction with the method of moments (MoM) is employed to optimize the geometry of the antenna after considering three objectives: cross(More)
A compact planar wideband microstrip antenna is introduced. The antenna is a log-periodic antenna with 7 dipole elements. The antenna is designed to function in the frequency range of 500 to 700 MHz. It has a dimension of 268 mm by 145 mm by 3 mm. The matching is better than -10 dB in the working bandwidth. The proposed antenna generates linear(More)
—In this paper, the power dissipated through different loss mechanisms including dielectric, conductor and radiation loss is calculated for the substrate integrated waveguide (SIW) and modified substrate integrated waveguide (MSIW). The applied computational method being appropriate for structures with periodic conducting parts allows one to calculate the(More)
Multiple-scale analysis is employed for the analysis of plane-wave refraction at a nonlinear slab. It will be demonstrated that the perturbation method will lead to a nonuniformly valid approximation to the solution of the nonlinear wave equation. To construct a uniformly valid approximation, we will exploit multiple-scale analysis. Using this method, we(More)
A rigorous and fast method for a Fourier-based analysis of 2-D dielectric-waveguide-coupled optical ring resonators (ORRs) is presented. As a first step, the structure under investigation is periodically repeated along a specific direction. The resulting periodic structure is then analyzed using a transmission-line formulation (TLF). For a sufficiently long(More)
By taking advantage of axial symmetry of the planar whispering gallery microresonators, the three-dimensional (3D) problem of the resonator is reduced to a two-dimensional (2D) one; thus, only the cross section of the resonator needs to be analyzed. Then, the proposed formulation, which works based on a combination of the finite-elements method (FEM) and(More)
The paper introduces a wavelength converter composed of a metallic finite 2-dimensional particle grating on top of an optical waveguide. The particles sustain plasmonic resonances which will result in the near-field enhancement and therefore, high conversion efficiency. Due to near-field interaction of the grating field with the propagating modes of the(More)