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In this paper, we propose a new architecture of 1 × 2 , 1 × 4 , 1 × 8 and 1 × 1 6 optical filter/power splitters operating around 1.55 μ m, based on a CPs 2D photonic crystal ring resonator for Modern Passive Optical Network (PON). This type of functionality, filtering/power splitting is introduced in this work for the first-time according literature. The designed device consists of a square array of GaAs dielectric rods immersed in air. The structure is designed and successfully simulated by the finite element method using the software COMSOL Multiphysics. From the results obtained, we note that the beam is evenly distributed for all output ports with total efficient transmissions of about 99.6%, 98.8%, 97.1% and 96.8% and low insertion losses of about 0.017, 0.052, 0.128, and −0.14 dB for the 1 × 2 , 1 × 4 , 1 × 8 , and 1 × 1 6 filter power splitter successively. [ABSTRACT FROM AUTHOR]

This paper demonstrates a novel configuration of half mode substrate integrated waveguide HMSIW bandpass selective filter based on Hilbert cells as DGS. Two 50-Ohm conventional micro-strip are used as feed lines. The filter is designed and optimized using CST Software, Where a parametric study is used to optimize its geometric parameters. In our design, six periodic Hilbert cells are used, which are work collectively with three transverse slots to generate the desired resonance frequency. The used dielectric substrate is FR4 with a relative permittivity of 4.3. The proposed filter operates at the frequency of 3.25 GHz with an insertion loss about of −2 dB and a rejection extended from 1 GHz to 3.2 GHz and from 3.4 GHz to 7 GHz respectively for the lower and the higher sides with a level more than −35 dB. The filter is fabricated and measured, where the obtained measurements show a clear crystal similarity with the simulated results. The proposed filter is considered for TD LTE applications. [ABSTRACT FROM AUTHOR]

In this paper, we have proposed a novel design and simulated an all-optical 1-bit half-adder based on photonic crystal. The fundamental structure is a square lattice of 2D Silicon rods, operating around the central wavelength of 1550 nm. The proposed half adder is composed of an optical combiner with two input ports, A and B are used for excitation power, and two parallel nonlinear ring resonators with two output ports, S and C, which are SUM and CARRY, respectively. In the creation of a nonlinear ring resonators at the resonant wavelength of 1550 nm and 1538 nm, respectively, we replaced the central rods with defect rods made of doped glass with a linear refractive index and nonlinear Kerr coefficient are about 1.4 and 10-14 m2/W. The optical intensity 10 mW/µm2 is used at the input ports A and B. The contrast ratios for output ports SUM and CARRY are about 13.71 dB, 13.67 dB and the total footprint is 198.9 µm2. The proposed structure has the advantage of simple design and small size with dimensions of 15.3×13 µm2. The normalized power values are low which correspond to 0 state in the output, whereas the power is reasonably high at output for logic stat 1, the power level for logic states "0" and "1" is equal to 4% and 94% respectively. The power difference with high and low logic values improves the constant ratios and reduce the bit error rate BER. The finite element method FEM and Plane-wave expansion PWE method are used to simulate the proposed structure under COMSOL Multiphysics software. [ABSTRACT FROM AUTHOR]

This paper demonstrates a novel form of substrate integrated waveguide SIW antenna array based on Fourier Series Equations. An optimized SIW power divider feeds the proposed structure where a micro-strip transition is used for impedance matching at 50 Ohm. The proposed antenna is traveling wave antenna type, in conventional methods the curve of antenna is of a linear or exponential form. In our method, we used the FSE to modify the contour of the antenna. The method is based on optimization of the Fourier series coefficients in order to maximize the gain for φ = π/2 and θ = π/2. The results of the return loss, the field's distribution, the radiation pattern and the realized gain were analysed. Furthermore, the antenna is designed in HFSS and CST with a comparison between them. The simulated return loss was compared with experimental measurements. The return loss of the proposed 1 × 4 antenna array is less than −10 dB at 5.5–6.8 GHz with an average gain about of 6 dBi and a peak gain about of 7.2 dBi. The proposed 1 × 4 antenna array is optimized with HFSS and designed using FR4 substrate, and considered in C-band for centimeters waves applications. [ABSTRACT FROM AUTHOR]

A miniaturized half-mode substrate-integrated-waveguide (HMSIW) based bandpass filter with defected ground surface (DGS) for sub-5G applications is presented in this research. The novelty in this article is the proposal of an original configuration of a SIW Filter composed of a mix of DGS cells; each couple of C shapes is etched exactly beneath of two cross shapes, which give us long rejection. We have used six periodic cross-shaped slots as DGS in top of the cavity plane for disturbing the current and creating stopband rejection, and we have also used three couples of C-shaped DGS cells in the bottom plane to improve the performances of the proposed filter. This novel bandpass filter is developed on a 1.54 mm-thick FR-4 (with relative permittivity of 4.3 and tangent loss of 0.025) operating in the band ranging from 3.4 GHz to 3.8 GHz with a bandwidth of 400MHz and having the size of 13:5 38:6mm2. The proposed HMSIW-based filter is simulated, fabricated, and measured. The measurement results are in decent agreement with the simulation results. [ABSTRACT FROM AUTHOR]

In this paper, we present a high pass filter based on half mode substrate integrated waveguide HMSIW technology dedicated to the transmission of microwave signals range from 6 GHz to 18 GHz. Taper is used for microstripe to SIW transition. We designed SIW line transmission using CST and HFSS simulators on a Rogers RT5880 substrate with dielectric constant of 2.2 and thickness of 0.508 mm, and we used the half mode technique for miniaturizing the filter size and achieving a size reduction about of 50%. The fabricated filter size is 60 12mm2. The lower measured return loss is about 􀀀51 dB. We compared the simulation results with measurement ones for validating our proposal. Good agreement between CST, HFSS and measurement results is observed. [ABSTRACT FROM AUTHOR]

In this article, two compact Substrate Integrated Waveguide (SIW) bandpass filters based on Defected Ground Structure (DGS) technology are proposed. Hilbert Cell of second order is the resonator shape proposed for the DGS of both filters, where the first filter DGS consists of five pairs, and the second one uses only three pairs. The pair used in the first filter consists of two cells located side to side whereas they are placed face to face in the second filter. In order to enhance the performance of the second filter and based on the evanescent-mode technique, three other pairs of first order Hilbert cells are engraved on the top layer. Both bandpass filters are designed to operate in C band with a measured bandwidth of 1.8 GHz for the first filter and 0.86 GHz for the second one. The proposed structures have the same physical dimensions, which is 38:1mm 16mm with different measured insertion losses of 􀀀2:5 dB and 􀀀2:7 dB. Both structures exhibit an upper stopband rejection with attenuation around 􀀀20 dB and 􀀀29 dB, respectively. The filters operate in a transmission bandwidth of [5.5 GHz|7.3 GHz] and [5.27 GHz{6.13 GHz] with a fractional bandwidth (FBW) of 28.1% and 15.09% for the first filter and the second filter, respectively. A good agreement is reported between the measured and simulated results. [ABSTRACT FROM AUTHOR]

This paper presents a comparative study that was done using genetic algorithm, improved particle swarm optimization, and hybrid technique genetical swarm optimizer approaches for the design of one-dimensional photonic crystal selective filters. The three evolutionary methods for synthesizing the geometrical parameters of a fiber Bragg grating structure from its layer thicknesses are proposed and demonstrated. The synthesis of the mono-band 1-D PhC selective filters is designed as a mono- objective problem, and these 1-D PhCs are composed of alternate Si and Air layers with thicknesses on micron scale. The main contribution of this paper is formed by the solution to this kind of problems. According to the literature, this hybrid methodology genetical swarm optimizer has been not dealt with before, when 1-D PhCs selective filters are considered. Comparison of the GA, IPSO, and GSO for the selected set of examples revealed an improvement of paramount importance in terms of error lowering and the number of iteration cycles diminution. [ABSTRACT FROM AUTHOR]

In this paper a defected ground structure (DGS) bandpass filter based on half mode substrate integrated waveguide (HMSIW) technology is proposed. We used vertical double circle complimentary split ring resonator (CSRR) as DGS etched on the top plane of the SIW cavity to constitute a multiple mode resonator and dumbbell DGS etched on the ground plane of the SIW cavity for enhance the filter performance. The taper line is used for transition between microstrip to SIW The simulation results obtained by CST and HFSS show that the proposed filter has a large transmitted bandwidth from 6.2 to 12.7 GHz. The higher simulated insertion loss is about -0.5 dB and the lower return loss is about -48 dB. The size of the designed filter is 60 × 9.8 mm2 which make it more compact compared to other published research works with a size reduction of about 50%. Good rejection are achieved under 6 GHz and upper 13 GHz. The good calculation of taper, the empirical parameters of the filter and the use many DGS cells in the bottom plane allowed us to obtain the good results. Good agreement between CST and HFSS simulation results. [ABSTRACT FROM AUTHOR]

In this paper the iterative rigorous approach is applied flexibly to complex Hilbert filters using structured computational grids. The wave concept iterative process (WCIP) is reviewed, focusing on their fundamental conception and simple algorithm, with the presence of defected ground structure (DGS) appearing as Hilbert curve ring (HCR) cells. The selected studied filters have shown increasing levels of sophistication and complexity that have properly contributed in evaluating the WCIP performance. To attain this purpose, the simulated computational results are demonstrated by measurements, and the iterative results, accurate enough, are obtained to some extent for the more sophisticated designs. [ABSTRACT FROM AUTHOR]

The aim of this paper was to propose and design a photonic crystal drop filter based on ring resonators and study its properties numerically. This structure is constituted in a two-dimensional square lattice. The resonant wavelengths of the PCRR proposed are λ =1.553 µm, and the extraction efficiency exceeds 99% with a quality factor of 5177. To study the all-optical OR and XOR logic gate function, we calculated the electric field distribution of the 2D photonic crystal for the 1.553 µmsignal light. In order to have a large selectivity of filtering and also of having a fast switching in the field of nonlinearity, we increase the number of ring resonators, and the latter are used for designing all optical logic gates which work using the Kerr effect equal to 10-6 m²/w. [ABSTRACT FROM AUTHOR]

This paper presents the numerical and experimental results of a miniaturized half‐mode substrate integrated waveguide HMSIW C‐band pass filter with defected ground structure DGS, using two slots and dumbbell shape defected ground structure. These two slots which are etched on the upper plane of the SIW cavity are used to constitute a multiple‐mode resonator, and the dumbbell‐shape fractal DGS etched on the bottom plane can considerably enhance the filter's performances. The manufactured band‐pass filter in half mode based on SIW technology has a size nearly half of that of a normal filter. The measurements results obtained by CST in C‐band show that the manufactured filter has a large transmitted bandwidth of about 1.53 GHz from 5.97 to 7.5 GHz. The higher measured insertion is about −2.6 dB and the lower return loss measured is about −34 dB. The size of filter design achieved is 7.48 × 38.12 mm2 which make it the more compact in comparison with some published works at the C‐band frequency. [ABSTRACT FROM AUTHOR]

A novel design of a double selective filter for integrated optics in two-dimensional photonic crystals operating at a wavelength of 1.31 and 1.55 µm is proposed in this paper. We focus particularly on filters transmission and selectivity enhancement. The two-dimensional photonic crystals filters are simulated by using a combination of three cascaded waveguides; these later are conceived by one missing row and with different rods radii for efficient filtering purpose. The properties of these photonic crystal structures are numerically investigated by using the two-dimensional finite-difference time-domain method and the numerical results are given for incident light wave having transverse electrical polarization. A final synthesized filter topology is presented and the maximum of transmission is found around 70% and 60% localized respectively near 1.31 and 1.55 µm wavelengths. [ABSTRACT FROM AUTHOR]

In this article, an innovative technique to design 1D and 2D annular ring unequally microstrip antenna arrays for the two modes TM11and TM12is introduced. The structure analysis is based on the modified cavity model, which allows to take into account the fringing fields effects along the ring-curved edges by employing dynamic permittivity. Design of linear and planar antenna arrays consider the optimization of the complex excitations values of the feeding network and the element locations first and a predefined magnitude’s Gaussian and uniform feed arrays of two modes second by using the genetical swarm optimizer method. The design of aperiodic linear antenna arrays is modeled as a single-objective problem, and the optimization of 2D aperiodic antenna arrays for bothEandHplanes and for both modes are also expanded to multi-objective cases. In terms of beam steering and low side-lobes level, the results presented in this article show interesting characteristics in the array factor response. Examples are given to illustrate the achievable performance. [ABSTRACT FROM AUTHOR]

In this paper, two classes of V-band substrate integrated waveguide (SIW) bends operating in V-band frequency in the range [58-63 GHz] for the $${90^{\circ}}$$ SIW bend with inductive via and in the range [57-68 GHz] for the circular SIW bend and corporate $${1\times4}$$ and $${1\times8}$$ SIW power dividers that provide equal power split with high isolation in all output ports operating in V-band [45-80 GHz] are presented and studied. The advantages of the SIW technique are its low profile, low cost, mass production, ease of fabrication and full integration with planar circuits. All the SIW bend topologies are optimized and designed to operate in the V-band frequency range. The bends and dividers are analyzed using the two-dimensional finite element method (2D-FEM). The analysis was performed in H-plane using a powerful full-wave method based on the two-dimensional finite element method (2D-FEM) programmed under MATLAB environment. The return losses, transmission coefficients and the field's distribution are exposed in this paper. To validate our results numerically, a comparison is made and the obtained results are compared with those given by the CST Microwave Studio. It is observed that the simulation computation time is reduced with good accuracy since the discretization was done only in two dimensions. [ABSTRACT FROM AUTHOR]

ABSTRACT In this article, a novel compact structure with a compact size and low insertion loss half-mode substrate integrated waveguide/high pass-filter dedicated for microwave signal guiding and high signal filtering that screen transmit-IEEE C-band signals is optimized, fabricated, and measured. The measurements results of the S parameters are compared with those provided by the commercial software CST Microwave Studio. Agreements between measurements data and the CST software results were achieved. It numerically compares how the transmission in C-band can be successfully achieved with HMSIW. The Half-Mode SIW Waveguide/High Pass-Filter design size achieved is 7.5 × 35 mm2. A size reduction of about 50% in comparison with a similar SIW Waveguide/High Pass-Filter has been achieved. The measured insertion loss is below −2 dB while the return loss is less than 10 dB. It is attractive which can be used for the radio communication system applications. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:414-418, 2016 [ABSTRACT FROM AUTHOR]

The main objective of this study is to optimize an optical component considered as an essential building block in wavelength division multiplexing applications. The work presented here focuses on the design of an optimum 1 x 8 compact splitter based on a two-dimensional (2-D) photonic crystal (PhC) in triangular unit cells exhibiting high transmission. It generates a contribution to the 2-D planar PhCs in the integrated optics field. These new materials may prohibit the propagation of light in certain directions and energies. We also optimize the splitter topologies in order to integrate them in optoelectronic systems as division components. To do so, the 2-D finite-difference time-domain method is employed to characterize the transmission properties. Simulation results show that total transmissions of about 86%, 78%, and 86% for the 1 x 2, 1 x 4, and 1 x 8 Y splitters, respectively, at output ports are obtained around the wavelength 1.55 µm widely used in optical telecommunications. It is demonstrated numerically that the corresponding total insertion losses for the three splitters are, respectively, about 0.65, 1.08, and 0.65 dB. The simulation results are presented and discussed. [ABSTRACT FROM AUTHOR]

A novel configuration of quad-band bowtie antenna suitable for wireless application is proposed based on accurate equivalent circuit model. The simple configuration and low profile nature of the proposed antenna lead to easy multifrequency operation. The proposed antenna is designed to satisfy specific bandwidth specifications for current communication systems including the Bluetooth (frequency range 2.4–2.485 GHz) and bands of the Unlicensed National Information Infrastructure (U-NII) low band (frequency range 5.15–5.35 GHz) and U-NII mid band (frequency range 5.47–5.725 GHz) and used for mobile WiMAX (frequency range 3.3–3.6 GHz). To validate the proposed equivalent circuit model, the simulation results are compared with those obtained by the moments method of Momentum software, the finite integration technique of CST Microwave studio, and the finite element method of HFSS software. An excellent agreement is achieved for all the designed antennas. The analysis of the simulated results confirms the successful design of quad-band bowtie antenna. [ABSTRACT FROM AUTHOR]

In this paper, integrated 2D photonic crystal narrow band filter design is achieved based on transmission spectra shift. The presented effective technique for the design of narrow band resonant filters obtained by one-missing-row and by choosing proper radii of air holes of the waveguide is proposed. The 2D photonic crystals are designed by utilizing cascaded waveguides with different radii of air holes. The results are presented for normal incident wave with TE polarizations with a narrow spectral bandwidth centered at λ = 1.55 μm. We also discuss the filtering process and its necessary modifications to achieve efficient filtering. A final synthesized filter topology is presented and a band from 1.53 μm to 1.57 μm around 1.55 μm is transmitted with a maximum transmission of about 77% with better performances is achieved. [ABSTRACT FROM AUTHOR]

During the last decade, selective photonic crystal filters have received much research interest in the fields of nanotechnology and optical interconnection network. The main focus of this paper consists of an analysis and a synthesis of one-dimensional photonic crystal selective filters. The optimization is performed by employing the simulated annealing algorithm. The filters synthesis is obtained by acting on the Bragg grating layer widths. Simulated annealing is applied to solve the PhC-1D filters synthesis problem in order to reduce the quadratic error and to obtain a desired transmission according to a Gaussian function defined in advance by the user. Starting from the Maxwell's equations for dielectric nonmagnetic structure, we show the derivation of the Helmholtz equation and find its solution for 1D layered structure. In addition, the boundary conditions and equation transformation to set of linear equations which are solved using Cramer's method are described thoroughly. This mathematical technique is then applied for computation of the transmission spectra of 1D perfectly periodic structure and structures with different defects. These results can be easily applied for design of selective filters. [ABSTRACT FROM AUTHOR]