ACES Publication Search
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| Title: | ACES Journal September 2018 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2163 KB |
| Title: | ACES Journal September 2018 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 838 KB |
| Title: | ACES Journal September 2018 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 15688 KB |
| Title: | A Finite Difference Time Domain Method for Passive Intermodulation Analysis of Nonlinear Metal-Metal Contact |
| Abstract: | The passive intermodulation (PIM) has gradually become a serious electromagnetic interference in the high-power and high-sensitivity RF/microwave communication system with the existence of the nonlinear metal-to-metal (MM) contacts. This paper proposes a finite difference time domain (FDTD) method for PIM analysis of nonlinear MM contacts. There are two kinds of models, the power series model and the equivalent circuit model, to describe the nonlinear MM contacts. Then the FDTD method is applied to analyze the nonlinear models so that the nonlinear current through the MM contact can be determined. For the microwave transmission devices, the PIM power level can be obtained by fast Fourier transform of the nonlinear current. For the microwave radiation devices such as antennas, the nonlinear currents are taken as a new electromagnetic transmitting source, the far-field scattering and PIM power level can be obtained by the FDTD method. Finally, a comparison between the simulation and experimental results is illustrated to verify the validity of the proposed method. |
| Author(s): | T. Li, W. Zhai, X. Li, X. Ma, J. Jiang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1737 KB |
| Title: | SSD Accelerated Parallel Out-of-Core Higher-Order Method of Moments and Its Large Applications |
| Abstract: | The performance of the parallel out-of-core Higher-order Method of Moments (HoMoM) is analysed in this paper. The I/O to hard disks significantly affects the performance of the out-of-core algorithm. In order to reduce the I/O time, solid state drives (SSD) with high read and write speeds are utilized. The size of the in-core buffer allocated to each process, IASIZE, is tuned to achieve the optimum performance of the out-of-core algorithm. Numerical results show that the out-of-core algorithm using SSD exhibits better performance than that using SAS hard drives. As a challenging application, a slot array with 2068 elements is analysed using this method. |
| Author(s): | Z. Lin, S. Zuo, X. Zhao, Y. Zhang, W. Wu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2313 KB |
| Title: | Design Optimization of Electromagnetic Devices using an Improved Quantum inspired Particle Swarm Optimizer |
| Abstract: | Quantum inspired particle swarm optimization (QPSO) is widely used global convergence algorithm for complex design problems. But it may trap into local optima due to premature convergence because of insufficient diversity at the later stage of search process. In this regard, to intensify the QPSO performance in preventing premature convergence to local optima. This work presents a novel QPSO approach using student t probability distribution method with mutation operator on particle with global best position. In addition, a new dynamic control parameter is proposed to tradeoff between the exploration and exploitation searches. The proposed method will intensify the improvement in its convergence behavior and solution quality. The proposed improve QPSO called IQPSO is tested on an electromagnetic design problem namely, the TEAM workshop benchmark problem 22. The experimental results showcase the merit and efficiency of the proposed method. |
| Author(s): | O. U. Rehman, S. Tu, S. U. Rehman, S. Khan, S. Yang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1497 KB |
| Title: | An Efficient Method to Study Shielding Effectiveness of Rectangular Enclosure with Wire Penetration |
| Abstract: | This paper presents a reliable and efficient analytical model to calculate the shielding effectiveness (SE) of a rectangular enclosure with wire penetration under plane wave illumination over frequency range of 0 to 2.5GHz. The wire is equivalent to monopole antenna, and the four-element lumped-parameter equivalent circuit for monopole antenna is established to represent the coupling process between electric field and the wire. Based on dynamic Green function, the approximate solution of the electric field distribution in the enclosure excited by the internal wire is derived, and Bethe's theory is used to calculate the approximate solution of the electric field distribution in the enclosure excited by the aperture when the aperture size is not negligible. Several cases are presented to verify the validity of the model. The effects of the length of the wire inside and outside the enclosure, wire penetration and observation point position as well as incident direction of plane wave on the SE are discussed in detail. Simulation result of the proposed model are in good agreement with that of the transmission line matrix (TLM) method. |
| Author(s): | P.-Y. Hu, X.-Y. Sun |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2689 KB |
| Title: | Robustness Evaluation of Split Ring Resonator Antenna System for Wireless Brain Care in Semi-Anatomical Ellipsoid Head Model |
| Abstract: | Robustness evaluation is a critical part to verify the applicability of wireless implantable devices. In this work, we present a semi-anatomical ellipsoid head model to evaluate the robustness of a split ring resonator inspired antenna system toward variable implant location, tissue layer thicknesses, and antenna orientation with respect to the human head. The system consists of a passive wearable part placed on the scalp and a cortical implant that carries a passive UHF RFID microsystem. According to our results, the antenna system is robust toward variability: it enables the remote powering of a -18 dBm RFID microsystem at distance between 0.5 and 1.1 meter at various locations and orientations with respect to the head and for skull thickness up to 1 cm. |
| Author(s): | S. Ma, L. Ukkonen, L. Sydanheimo, T. Bjorninen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2167 KB |
| Title: | Multiple Human Targets Detection and Localization Using Leaky Coaxial Cable Sensing Technique |
| Abstract: | Leaky coaxial cable (LCX) not only widely applies to the wireless communication systems, but also used as a LCX sensor for the intrusion detection systems (IDS). For evaluating the usability of the specialized LCX, the electrical parameters and the radiation pattern of the LCX sensor are measured. Moreover, in order to achieve the multiple targets localization, the novel location algorithm is proposed for the IDS based on the specialized LCX sensor in the VHF band. In this paper, the multiple targets are identified precisely by the synchronous subtraction, the time-domain digital pulse compression and the window function. By emitting a chirp signal into the LCX sensor, the echo signal containing the targets’ response is received by the signal receiver (Rx). Then the pulse accumulation can be used for decreasing the noise signal in the digital signal processor (DSP), and the peak characteristics of the targets’ echo signal are improved by the pulse compression and the Kaiser window function. Finally, by calculating the delay time of the echo signal after using the synchronous subtraction, the targets locations are obtained. The results show that transmission attenuation of the specialized LCX is 0.75 dB/100m and its coupling Loss is 71.63dB, and S11 is -39.9dB when the central frequency is 100MHz. The range resolution of the intruder detection system based on LCX sensor is as small as 3.32m and the positioning accuracy is less than 0.8m, which realizes the multiple targets detection and good localization results. |
| Author(s): | Q. Guan, H. Lu, C. Chen, C. He |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2121 KB |
| Title: | Conformal Load-Bearing Antenna Structure for MIMO Applications |
| Abstract: | A broadband, airfoil-integrated, VHF antenna is introduced for conformal load-bearing structures (CLAS) applications. A two-layer antenna is developed and the effects of integration with a composite sandwich structure are investigated. A prototype structure is fabricated that exceeds an octave of measured impedance bandwidth and simulated gain and pattern bandwidth. Envelope correlation coefficient (ECC) and simulated radiation patterns are used to gauge feasibility of the structure for use in a MIMO application on a twin-tail drone. |
| Author(s): | D. L. Zeppettella, M. Ali |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2146 KB |
| Title: | Wideband Dual-polarized Vivaldi Antenna with Gain Enhancement |
| Abstract: | A wideband dual-polarized Vivaldi antenna covering 1.85-18.3 GHz band with enhanced gain is presented in this letter. The proposed antenna consists of two Vivaldi antenna elements (VAEs), which are designed based on the conventional Vivaldi antenna. Dual-slot structure is employed to improve the gain of the conventional Vivaldi antenna. As a result, sphericallike waves across the slot aperture of the conventional Vivaldi antenna can be transformed to be plane-like waves and thus gain enhancement can be achieved. In order to extend lower frequency limit of the VAE, elliptical slots are adopted. The proposed dual-polarized Vivaldi antenna is obtained by combining two VAEs in a cross-shaped form. The prototype is simulated, fabricated, and measured. A good agreement between EM simulated and measured results evidently validates the proposed antenna. |
| Author(s): | H. Lv, Q. Huang, J. Hou, J. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2769 KB |
| Title: | UWB Gain Enhancement of Horn Antennas Using Miniaturized Frequency Selective Surface |
| Abstract: | In this work, enhancement of the radiation performances of horn antennas are worked out within their operation bandwidth by placing the miniaturized Frequency Selective Surface (FSS)s perpendicularly into the inner part of their flares. Here each FSS consists of only a single miniaturized double-sided inverted Tshaped square unit cell designed on the low-cost FR4 with relative permittivity 4.4, loss tangent 0.0035 and thickness 1.58 mm in 3D CST environment so that it is able to focus the propagating electromagnetic waves to increase the directivity properties like a dielectric lens, while keeping the mismatching characteristics with less size and low manufacturing cost compared to its counter parts. Herein an exponentially tapered TEM horn with the operation bandwidth of 5-13 GHz is taken as an example horn antenna for measurements. From the measured results of the prototyped module, it can be observed that the proposed module keep mismatching characteristics of the horn antenna, meanwhile the gain and beam widths are enhanced to amplify the signal in the operation band without any increase in the total volume of the module or making the design bulky. Thus, it is expected that this methodology can be implemented to horn antennas effectively reducing volume and cost of communication systems. |
| Author(s): | M. A. Belen, F. Gunes, P. Mahouti, A. Belen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2272 KB |
| Title: | A Low-Profile Miniaturized Frequency Selective Surface with Insensitive Polarization |
| Abstract: | In this letter, a low-profile miniaturized broadband bandpass frequency selective surface (FSS) is proposed. The proposed structure consists of a convoluted dipole metal layer and its complementary pattern, which are separated by a dielectric substrate with a thickness of 0.003lambda0, where lambda0 is the resonant wavelength in free space. The cell size of the proposed FSS is only 0.03lambda0 × 0.03lambda0. Furthermore, 3 dB bandwidth of the proposed FSS is approximately 50% for the normal incidence. Low profile and miniaturization of the structure element contribute to the great stability of frequency response under the incident waves with different incident angles and polarizations. To better understand the operational principle of the proposed FSS, the equivalent circuit model is presented. The proposed FSS prototype was fabricated and measured to validate the design. |
| Author(s): | M. Wang, L. Zhao, J. Wang, X. Liang, S. Zhang, Y. Li, W. Yu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2195 KB |
| Title: | The Design of a High Gain Dual-Polarized Quad-Ridged Circular Horn Antenna for Wideband EMC Test Applications |
| Abstract: | This paper presents the design of a high gain broadband quadruple-ridged circular horn antenna for Electromagnetic Compatibility (EMC) testing. The proposed antenna contains a wideband feed structure as a transition between coaxial line and quad-ridged circular waveguide behind the conical horn antenna. The wideband matching between impedances at the apertures of the feed and the horn is achieved with a tapering at the flare section along the horn length, which is obtained after a detailed investigation of various tapering profiles. The antenna is designed to operate in horizontal and vertical polarizations (dual linear polarization) simultaneously in EMC tests. This implementation is found to present a return loss greater than 10 dB, isolation level higher than 28 dB, high-gain (minimum 13.6 dBi) and low-gain variation of 4.5 dBi within the frequency range of 1-6.75 GHz (6.75:1 bandwidth) at both polarizations, which is a desired feature in radiated emission and immunity tests. |
| Author(s): | B. Solak, M. Secmen, A. Tekin |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2407 KB |
| Title: | Air Gap Effect on Antenna Characteristics of Slitline and Stripline Dipoles on an Extended Hemispherical Lens Substrate |
| Abstract: | This paper presents the effect of an air gap introduced between a planar feed and an extended hemispherical lens on the antenna’s impedance, current distribution and radiation characteristics. Two selected planar feeds for study are slitline dipole and stripline dipole. The results showed that as a small gap is introduced, the input impedance of the slitline dipole was almost remained unchanged while that of the stripline dipole was changed remarkably. More importantly, the boresight gain and radiation efficiency of the slitline dipole was improved whereas those of the stripline dipole were degraded with the presence of this air gap. An overall performance comparison for these two designs will be detailed in the paper. This study provides useful guidelines of choosing the proper feed for THz integrated lens antenna applications, especially for indoor THz communication applications such as wireless local area networks and wireless personal area networks in the 300 GHz band. |
| Author(s): | T. K. Nguyen, H. H. Tran |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2194 KB |
| Title: | Optimization and Design of Multi-ring Pole Pieces for Small-sized Permanent Magnetic Resonance Imaging Magnet |
| Abstract: | In magnetic resonance imaging (MRI) system, the main magnet creates a static magnetic field, which largely determines the final imaging quality. Pole pieces of pure-iron are commonly used to improve the field homogeneity in the imaging region. In this work, we attempt to design a novel configuration of multi-ring pole pieces for a small animal MRI system. Based on the model of a small H-type permanent magnet, the magnetic field is calculated using the finite element method, which considers the nonlinearity of the ferromagnetic materials. The pole piece was designed with the particle swarm optimization (PSO) algorithm. The results show that, the optimal multi-ring pole pieces can effectively reduce the uniformity about 10-20 ppm (10-6), with a better performance compared with the flat and traditional onering pole piece configuration. |
| Author(s): | Y.-Y. Cheng, T. Hai, Y.-B. Zheng, B.-L. Li, L. Xia |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1784 KB |
| Title: | Loss Analysis of Wideband RF MEMS Shunt Capacitive Switch in T and Pi-Match Configurations |
| Abstract: | A wide bandwidth coplanar-waveguide (CPW) based RF MEMS capacitive shunt switch with pi-matched & T-matched having high impedance transmission lines is designed and simulated for broadband (18-40 GHz) application. The effects of variation in membrane width (50 & 70 mu m) of the switch and high-impedance transmission line length (300 – 600 mu m) between the switch structures on scattering parameters are studied. The variation in beam width has very little effect on return loss of the switch in up-state. The reduction in high-impedance transmission line length yields marginal improvement in return loss. In the down-state configuration, the return loss showed negligible change with the variation in beam width and high-impedance transmission line length. The isolation is found improved with the increase in beam width and high-impedance transmission line length in whole frequency range. Simulating the technical performance demonstrates the greater improvement in RF characteristics of the switch particularly in return loss in up-state position. 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, P. Thiruvalar Selvan, S. Raghavan |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1832 KB |
| Title: | Interference Effects of Via Interconnect in Three Layer Printed Circuit Board |
| Abstract: | Cylindrical vias are commonly used for interconnection in multilayered Printed Circuit Board (PCB) design. The RF current through vias causes radiated interference to adjacent traces. This paper describes an analytical method of computing the radiation from cylindrical via using the electromagnetic theory. Three layer printed circuit board consisting of three traces on the top of a dielectric substrate, a middle orthogonal trace and a ground plane at the bottom, is considered. The RF voltage coupling at the terminations of the traces due to the near field radiation from the via is computed. The reactive couplings between the traces are determined from the parasitic elements using transmission line equations. The total coupling obtained from analytical method is compared with those of modeling and simulation with Ansoft HFSS software tool. The total crosstalk is also measured using an available Network Analyzer. A good agreement is found. The changes of radiated coupling with the change of position of via, trace separation and trace length are also investigated. This paper shows that the analytical method is a useful tool for predicting interference in PCB without using expensive simulation software. |
| Author(s): | A. Ghosh, S. K. Das, A. Das |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1882 KB |
| Title: | Data-Driven Arbitrary Polynomial Chaos for Uncertainty Quantification in Filters |
| Abstract: | A non-intrusive arbitrary polynomial chaos (aPC) method is applied to a problem of a band-stop filter with geometrical imperfections. The construction of aPC scheme only requires evaluating a finite number of moments, and does not involve assigning analytical probability density functions for the uncertain parameters of a stochastic model. Therefore, aPC is well suited for applications where the uncertain parameters are represented by raw data samples, as with the case of experimental measurements. The numerical examples show that the aPC approach is accurate even with a limited number of input samples. |
| Author(s): | O. J. Alkhateeb, N. Ida |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 9 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1795 KB |