ACES Publication Search





There are 23 search results for:



Title: ACES Journal April 2016 Cover
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 2501 KB

Title: ACES Journal April 2016 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 101 KB

Title: ACES Journal April 2016 Full
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 16352 KB

Title: A Multiscale Algorithm for Eddy-Current Nondestructive Evaluation Based On Volume-Integral Equations: Initial Concepts
Abstract: The use of coupled integral equations and anomalous currents allows us to efficiently remove ‘background effects’ in either forward or inverse modeling. This is especially true when computing the change in impedance due to a small flaw in the presence of a larger background anomaly. It is more accurate than simply computing the response with and without the flaw and then subtracting the two nearly equal values to obtain the small difference due to the flaw. In this paper, we compute the change in impedance of a probe due to a flaw in the presence of a much larger background anomaly, when the probe, which consists of a coil with a ferrite core, lies within the host region, and then apply the model and algorithm to the problem of inspecting a bolt hole in a plate or other layered medium with a ‘SplitD’ eddy-current probe.
Author(s): R. K. Murphy, H. A. Sabbagh, E. H. Sabbagh
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 667 KB

Title: Wire Fault Diagnosis Based on Time-Domain Reflectometry and Backtracking Search Optimization Algorithm
Abstract: The development of a robust and accurate fault diagnosis approach under various system and fault conditions is a research area of great interest. The objective of this paper is to develop a new non-destructive approach for wiring diagnosis based on Time Domain Reflectometry (TDR) in one hand and on Backtracking Search Optimization Algorithm (BSA) in the other hand. Real-world case studies are investigated to demonstrate the effectiveness and robustness of the proposed approach. Simulation results evaluated from experimental data demonstrate that the proposed approach can be used for effective diagnosis of complex wiring networks.
Author(s): H. Boudjefdjouf, H. R. E. H. Bouchekara, F. de Paulis, M. K. Smail, A. Orlandi, R. Mehasni
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 723 KB

Title: Compact UWB Antenna with Triple Band-Notches Using C-Shaped and S-Shaped Structures
Abstract: A semi-ellipse planar monopole UWB antenna with triple band-notched characteristics is presented. The proposed antenna with three band notches can operate in 3-13.9 GHz which covers the UWB (3.1-10.6 GHz) frequency range. Triple band-notched characteristics is achieved by etching a C-shaped slot on main radiator and adding two novel modified S-shaped cells on either side of microstrip line. The antenna is designed to reject the WiMAX (3.3-3.7 GHz), WLAN (5.15-5.825 GHz), and the downlink of X-band satellite communication systems (7.25-7.75 GHz). The proposed antenna is designed on FR4 substrate of size 20×26×1 mm3. Details of the antenna design and analysis are presented in this paper.
Author(s): Z. Ma, F. Dong, Z. Han, S. Han, Q. Xue
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 401 KB

Title: FR4-Only Microstrip Reflectarray Antennas for 5.8 GHz Dual-Polarized Wireless Bridges
Abstract: Low-cost antennas are suggested for 5.8 GHz narrow-band, low-power and dual-polarized wireless bridges based on pure microstrip flat reflectarrays. A single layer of the cheapFR4 epoxy is exploited as the substrate for both of the feed and reflector. Detailed design procedure for the feed is reported. Three different elements are used for designing the reflector including rectangular dipole, unbalanced cross and square patch. Using method of moments, performance of the designs is compared from various aspects, including reflector diameter, computational cost, gain, half-power beam-width and polarization purity.
Author(s): B. Honarbakhsh
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 941 KB

Title: Optimal Design of PCS Ceramic Microwave Filters using the Differential Evolution Algorithm
Abstract: The optimal geometrical design of a ceramic microwave filter according to the specifications of the downlink band of the PCS-1900 mobile communications protocol is investigated in this paper. An efficient combination of the Differential Evolution Algorithm and the Finite Element Method leads to the optimal values of four design parameters.
Author(s): T. I. Kosmanis, I. T. Rekanos, S. P. Tsitsos
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 439 KB

Title: An Accurate High-Speed Method for Mutual Inductance Calculations of Coplanar Disk Coils Using Generalized Hypergeometric Functions
Abstract: Traditional method using integral of the Bessel and Struve functions is not suitable for calculating the mutual inductance between two coplanar disk coils. Considering the monotonicity of modified Bessel and Struve functions, an alternative method using these monotonic functions is applied to calculate the mutual inductance, and numerical evaluations can be accelerated considerably. Series solutions using the generalized hypergeometric functions are further obtained by solving the infinite integrations, and these series are compared with the aforementioned integral methods. The numerical results show that the series solutions are much more faster than the integral ones, and with the series method, results of very high accuracy can be obtained within a small fraction of one second in most cases. Furthermore, we point out and prove the existence of the decoupling positions at which the mutual inductance will vanish.
Author(s): Y. Luo
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 521 KB

Title: A New High Performance Hibiscus Petal Pattern Monopole Antenna for UWB Applications
Abstract: A new ultra wideband (UWB) antenna is proposed that can be efficiently used for different wireless UWB applications. The antenna structure has a very simple patch with Hibiscus petal pattern. The antenna is designed on a 31×31 mm2 Rogers RT/duroid 5870 substrate with permittivity 2.33, loss tangent 0.0012, 1.57 mm thickness and a 50 ohm impedance microstrip fed line. Different parts of antenna are analyzed to optimize the antenna properties. The novel patch of the antenna is modified to achieve the desired wide bandwidth behavior. The simulation results show that the antenna has an impedance bandwidth of 145% from 3.2 to 20 GHz with VSWR<2, a stable omnidirectional radiation pattern, an average gain of 5.1 dBi and the average radiation efficiency is 85%, which is ideal for use in UWB applications. The proposed antenna was successfully prototyped and the measured results are consistent with simulation.
Author(s): M. Z. Mahmud, S. Kibria, M. Samsuzzaman, N. Misran, M. T. Islam
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 1261 KB

Title: A Planar Monopole Antenna with Switchable Dual Band-Notched UWB/Dual-Band WLAN Applications
Abstract: In this paper, a planar monopole antenna in ultra-wide band (UWB) frequency range from 2.8 to 10.2 GHz with two notch band of 3.3–4.2 and 4.9–6 GHz is presented. The dual band-notched UWB antenna can be switched to dual wireless local area network (WLAN) frequency bands of 2.2–2.6 and 5–5.9 GHz. The proposed antenna has a simple structure and compact size of 15×15 mm2. The antenna in the UWB function uses a circular radiator monopole with an embedded slot in the ground plane. Several stubs are etched on the radiator as rejecting elements. A parasitic element with an ideal switch is used in the backplane to achieve the dual-band WLAN function. In this mode, the stubs in the radiator are as resonating elements. The function of the antenna can be changed by switching states that make the various operating bands. The measurement and simulation results show that the antenna has good characteristics for cognitive radio application where the UWB antenna is required for spectrum sensing and the WLAN band antenna is used for reconfigurable operation.
Author(s): M. M. Fakharian, P. Rezaei, V. Sharbati
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 954 KB

Title: Ultra-Wideband Planar Antenna with Notched Bands at 3.5/5.5 GHz
Abstract: In this paper, a microstrip planar antenna with notch bands at 3.5/5.5 GHz is proposed for ultra- wideband communication. An e-shape parasitic slit and an inverted C-shape slit are imprinted beneath the radiating patch to generate notch bands to suppress the interference from WiMAX and WLAN respectively. The experimental results confirmed that the fabricated prototype with a very small size has achieved an UWB operating band for VSWR ? 2 with two notched bands covering frequencies of 3.32 - 3.76 GHz and 5.2 - 5.92 GHz. The presented design achieved a good gain except at notched bands and exhibits stable omnidirectional radiation patterns. In this design, filter elements are embedded only on one side of the substrate without cutting any slot/s in the radiating element/ground plane and no modification of the patch or the ground plane is required which gives the proposed design an advantages over many designs reported for the same applications.
Author(s): R. Azim, M. T. Islam
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 638 KB

Title: Design of a Compact Wideband Balun Bandpass Filter with High Selectivity
Abstract: A new design method for compact wideband balun bandpass filter (BPF) with high selectivity is proposed in this paper. To achieve wide operation bandwidth, the first three resonant modes, i.e., one odd mode and two even modes, of a folded stepped-impedance multi-mode resonator are utilized and arranged inside the passband. Then, to realize good balance-to-unbalance performance, a microtrip to coplanar stripline transition structure is introduced in the design. Finally, a balun BPF characterized with both wide bandwidth and high selectivity has been eventually achieved through proper coupling topology. Besides, to further demonstrate the validity of our design concept, a practical microstrip wideband balun BPF with the fractional bandwidth (FBW) of 66% and two respective transmission zeros located at 1.4 GHz and 4.2 GHz is designed, fabricated, and measured. As expected, both the simulated and measured results exhibit good filtering and balun performance.
Author(s): H. Ma, J. Lu, Y. Li, L. Liu, J. Wang
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 526 KB

Title: Novel Compact Branch-Line Coupler Using Non-Uniform Folded Transmission Line and Shunt Step Impedance Stub With Harmonics Suppressions
Abstract: In this paper, a novel compact branch-line coupler (BLC) using non-uniform folded transmission line (NUFTL) and shunt step impedance stubs (SSISs) with harmonics suppressions is presented and its design procedure is discussed. In the proposed structure, in order to reject the unwanted harmonic pass bands, a pair of SSISs is implemented along the ports of the coupler. To minimize the physical size of the coupler, NUFTL are used instead of uniform transmission lines in each arm of the branch-line. With the proposed approach, the size of the quarter-wavelength transmission line in the branch-line can be reduced greatly. The presented BLC has a compact size while showing good return loss and insertion loss characteristic in the frequency band of interest. Good agreement exists between the simulated and measured results.
Author(s): Sh. Nouri, J. Nourinia, N. Valizade, B. Mohammadi, A. Valizade
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 592 KB

Title: CPW Dependent Loss Analysis of Capacitive Shunt RF MEMS Switch
Abstract: CPW (CoPlanar Waveguide) plays major role in design of RF MEMS switch to improve the performance in terms of losses and required bandwidth of operation. This paper proposes the analyses of the mechanical characteristics on the electrical performance of the Capacitive Shunt RF MEMS (CSRM) switch based on various CPW structures and contact area roughness of the switch using electromagnetic 2.5D ADS simulator. The result of momentum method was analyzed up to the K-band frequency of 100 GHz. The result shows that the CSRM switch with two conductor CPW coupler has a maximum isolation of -46 dB with operating bandwidth up to 90 GHz at the resonant frequency of 50 GHz. In order to validate the obtained result, Artificial Neural Network (ANN) has been trained using ADS result. Comparison shows good agreement between ADS and ANN results.
Author(s): S. Suganthi, K. Murugesan, S. Raghavan
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 468 KB

Title: Dual Band and Dual Mode Microstrip Antenna for Body Centric Wireless Communication
Abstract: A compact dual band and dual mode microstrip patch antenna, suitable for body centric wireless communication (BCWC) network is presented. The BCWC network works in two on-body and off- body modes. The proposed antenna has an outward radiation pattern for the off-body mode, which is suitable to communicate from on-body devices to off- body unite. Moreover, the antenna has an end-fire radiation pattern for the on-body mode, to communicate with other co-located worn devices from which data can be easily gathered. The proposed antenna resonances at 2.44 GHz (IEEE 802.11b/g) with 7.1 dB gain and linear polarization for the off-body mode and also at 5.43 GHz (IEEE 802.11a) with 6.6 dB gain and circular polarization for the on-body mode. Free space and on-body simulated and measured performances of the proposed antenna are shown. Specific absorption rate (SAR) value is also studied. The results show that the maximum averaged 10gr SAR is 0.26W/Kg for on-body mode when the antenna is placed on the chest of the human body model.
Author(s): S. Khaledian, Z. Atlasbaf
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 585 KB

Title: A Novel Coupling Structure for Changing the Coupling Nature Between TE01?-mode Dielectric Resonator and Combline Resonator
Abstract: In this paper, a novel coupling structure is presented, which could easily change the coupling nature between combline resonator (CR) and dielectric resonator (DR). This coupling structure is based on electric field orientation of DR operating in TE01?-mode, through altering the direction of copper sheet in the DR, the excited orientation of electric field would be changed along with the coupling nature between two resonators. To prove this method, two filters using cascaded triplet (CT) coupling relation are designed, fabricated and measured, showing the controllable coupling nature between CR and DR. Measured results confirmed the predicted performance.
Author(s): B. Yu, B.-F. Jia, Z.-J. Zhu
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 645 KB

Title: The Substrate Integrated Waveguide T-junction Power Divider with Arbitrary Power Dividing Ratio
Abstract: An X-band H-plane wideband substrate- integrated waveguide (SIW) T-junction power divider with unequal-power-division ratio is presented. Several inductive posts are used to have arbitrary power dividing ratio and also to control the phase difference. The position and diameter of these posts tune the power-split ratio and the phase difference in whole bandwidth. Parametric studies have been done to choose the best positions and diameters to get better results. Two different prototypes have been verified the proposed technique. They are designed and fabricated at a center frequency of 11 GHz. The measured input impedance bandwidths are 54% for ?out =3 dB and 45% for ?out =6 dB respectively.
Author(s): A. Piroutiniya, P. Mohammadi
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 1267 KB

Title: Small Wearable Meta Materials Antennas for Medical Systems
Abstract: Communication industry is in rapid growth in the last years. Efficient small antennas are crucial in the development of medical systems. Low efficiency is the major disadvantage of small antennas. Meta material technology is used to improve the efficiency of small antennas. Design tradeoffs, computed and measured results of wearable meta-materials antennas with high efficiency are presented in this paper. All antennas were analyzed by using 3D full-wave software, ADS. The antennas electrical parameters on the human body are presented. The gain and directivity of the patch antenna with split-ring resonators, SRR, is higher by 2.5 dB than the patch antenna without SRR. The resonant frequency of the antennas with SRR is lower by 5% to 10% than the antennas without SRR. The resonant frequency of the antenna with SRR on human body is shifted by 3%.
Author(s): A. Sabban
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 1410 KB

Title: A Hybrid Explicit-Implicit Scheme for Spectral-Element Time-Domain Analysis of Multiscale Simulation
Abstract: The multiscale simulation usually leads to dense meshes discretization for fine structures, thus making time step size of the spectral-element time-domain (SETD) method extremely small to ensure stability for explicit scheme. In this paper, a hybrid explicit-implicit scheme for SETD is proposed to deal with the simulation of multiscale electromagnetic problems. The central-difference is applied for the coarse region with large cells and the Newmark-Beta scheme is for the fine region with small cells. Then a large size of time step can be selected in the whole domain instead of the one limited by the smallest cell. When solving the matrix equation formed by the implicit scheme, two approaches are employed. One uses the sparse matrix solver UMFPACK directly and the other involves an explicit and iterative scheme. Numerical results show that the hybrid method is an efficient alternative to conventional SETD method for multiscale simulation.
Author(s): H. Xu, D. Z. Ding, R. S. Chen
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 573 KB

Title: Broadband CRLH Beam Scanning Leaky-Wave Antenna Designed on Dual- Layer SIW
Abstract: This paper presents a broadband Composite Right/Left Handed (CRLH) leaky-wave antenna operating above the cutoff frequency based on the substrate integrated waveguide (SIW) is introduced. The proposed antenna consists of two dielectric layers, as the host of the structure, an interdigital capacitor radiation slot and a pair of twisted inductive post. The beam scanning capability of the leaky wave antennas will be achieved using CRLH, which allows radiation both in RH and LH regions. The design procedure begins with designing a unit-cell and evaluated with dispersion diagram. Based on the proposed unit-cell, the antenna structure consists of 10 units-cells, is developed at the X-band. The bandwidth of 66% has been obtained beside 105° of the beam steering angle both in the RH and LH regions, while the frequencies change from 6.5 GHz up to 9.5 GHz. The proposed antenna could be used in radar and imaging systems.
Author(s): M. Niayesh, Z. Atlasbaf
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 728 KB

Title: Evaluation of E-Field Distribution and Human Exposure for a LTE Femtocell in an Office
Abstract: Firstly, the finite-difference time-domain (FDTD) method was used to calculate electric fields emitted from a long-term evolution (LTE) femtocell placed at the left-hand side of an empty office at frequencies of 700, 860, 1990, and 2600 MHz. After validating the accuracy of the FDTD method, the FDTD method was used to calculate electric field distributions inside the office, with and without the presence of 20 people and furniture for the LTE femtocell placed near the center of a horizontal plane with a distance of 1.0 m from the ceiling and transmitting a power of 10 dBm. Simulated electric fields at most of the locations on the horizontal plane with a height of 1.0 m above the floor for the office with and without the presence of 20 people and furniture are found in the range of -10 to -30 dBV/m, which means a good signal will be picked up in the office. The maximum power density emitted from the LTE inside the office and maximum localized SAR induced in a standing person are far below the ANSI/IEEE safety standard for public exposure in uncontrolled environments.
Author(s): H.-Y. Chen, S.-H. Wen
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 2643 KB

Title: Light-Weight Wide-Band Metal-Only Reflectarray Antennas
Abstract: A new class of metal-only reflectarray antennas (RAs) is reported. The proposed RA is based on a unit-cell constructed from a short-circuited conducting square. This, compared to the previously reported metal-only designs, leads to less weight and fabrication complexity. In addition, bandwidth enhancement can be accomplished by extending the idea to multi-layer unit cells. Gain stability with less than 0.1 dB variation over 1 GHz bandwidth at 12 GHz center frequency is achieved using the proposed two-layer reflector.
Author(s): B. Honarbakhsh
File Type: Journal Paper
Issue:Volume: 31      Number: 4      Year: 2016
Download Link:Click here to download PDF     File Size: 710 KB