ACES Publication Search
There are 19 search results for:
| Title: | ACES Journal August 2018 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2163 KB |
| Title: | ACES Journal August 2018 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 819 KB |
| Title: | ACES Journal August 2018 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 14793 KB |
| Title: | Single-Snapshot Time-Domain Direction of Arrival Estimation under Bayesian Group-Sparse Hypothesis and Vector Sensor Antennas |
| Abstract: | In this work, an optimal single-snapshot, time domain, group-sparse optimal Bayesian DOA estimation method is proposed and tested on a vector sensors antenna system. Exploiting the group-sparse property of the DOA and the Bayesian formulation of the estimation problem, we provide a fast and accurate DOA estimation algorithm. The proposed estimation method can be used for different steering matrix formulations since the optimal standardization matrix is computed directly from the knowledge of the steering matrix and noise covariance matrix. Thanks to this, the algorithm does not requires any kind of calibration or human supervision to operate correctly. In the following, we propose the theoretical basis and details about the estimation algorithm and a possible implementation based on FISTA followed by the results of our computer simulations test. |
| Author(s): | M. Muzi, N. Tedeschi, L. Scorrano, V. Ferrara, F. Frezza |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1896 KB |
| Title: | Efficient Sub-Gridded FDTD for Three-Dimensional Time-Reversed Electromagnetic Field Shaping |
| Abstract: | Based on the space-time focusing property of the time reversal technique, the electromagnetic field shaping of arbitrary patterns is easily realized by using an efficient sub-gridded finite-difference time-domain (FDTD) method in this paper. It is an electrically large and multiscale problem if the desired shaping field requires high resolution. With the advantage of the sub-gridded scheme, the electromagnetic field shaping region can be locally discretized with dense grids, which is embedded in global coarse grids. Then, the Courant-Friedrich-Levy (CFL) limit can be extended by employing the spatial filtering scheme to filter out the unstable harmonics inside the dense grid region. Thus, the number of total unknowns is largely reduced and a common time step size chosen from the CFL limit of the coarse grid is used throughout the computational domain. Simulation results with two kinds of boundary conditions are provided to demonstrate the availability of the spatially-filtered sub-gridded FDTD method for electromagnetic field shaping. |
| Author(s): | X.-K. Wei, W. Shao, X. Ding, B.-Z. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2287 KB |
| Title: | Effect of Symmetry on Insertion Loss in SRR and CSRR Transmitarray Unit Cells Implementing the Element Rotation Method |
| Abstract: | Insertion loss variation with respect to rotation angle is examined for geometrically symmetrical and unsymmetrical split ring resonators (SRR) and complementary split ring resonators (CSRR) transmitarray unit cells implementing the element rotation method. Generalized design conditions for the implementation of the method on transmitarrays are derived. Based on the S-parameters obtained by full-wave electromagnetic simulations and field analysis, it is shown that the symmetry of CSRR unit cells has an important effect on decreasing insertion loss variation with respect to rotation angle. Up to 3 dB improvement in insertion loss is achieved for the symmetrical single ring double split CSRR type unit cell. It is also shown for two nested non symmetric SRR unit cells that, insertion loss is almost independent of the element rotation when the transmission is mainly provided by the symmetrical part of the unit cell. |
| Author(s): | E. Erdil, K. Topalli, O. A. Civi |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2186 KB |
| Title: | Semi-inverse Method to the Klein-Gordon Equation with Quadratic Nonlinearity |
| Abstract: | Nonlinear electrical and mechanical systems have been widely used in the industry electronics and consumer devices. Many numerical algorithms can be employed to obtain the numerical solutions of the nonlinear dynamics or electromagnetic equations. However, it takes a lot of time and decreases the solution accuracy. In this paper, a novel method, called Semi- Inverse Method, is proposed to seek solitary solutions of nonlinear differential equations. The Klein-Gordon equation with quadratic nonlinearity is selected to illustrate the effectiveness and simplicity of the suggested method. |
| Author(s): | W. Yan, Q. Liu, C.M. Zhu, Y. Zhao, Y. Shi |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1578 KB |
| Title: | Stochastic Analysis of Multi-conductor Cables with Uncertain Boundary Conditions |
| Abstract: | This paper provides two novel Stochastic Galerkin Method strategies to undertake stochastic analysis of the crosstalk in the multi-conductor cables with uncertain boundary conditions. Two different uncertain boundary conditions, stochastic lumped source and stochastic lumped load, are considered into stochastic Transmission Line Model. With the help of the Feature Selective Validation, it is verified that the proposed strategies is accurate by comparing with the reference results provided by Monte Carlo Method. At last, advantage of the proposed strategies in computational efficiency is presented. |
| Author(s): | G. Zhang, J. Bai, L. Wang, X. Peng |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1795 KB |
| Title: | Design of a Microstrip-Fed Printed-Slot Antenna Using Defected Ground Structures for Multiband Applications |
| Abstract: | This paper presents the design of a microstrip-fed, planar-printed, slot antenna using defected ground structures (DGSs) for multiband applications. The antenna structure consists of two groups of five straight slot elements. The slot elements in each group are of the same width but different lengths on the ground plane and separated by a small strip and a slot cut on both sides of the strip to interconnect the group of slots with each other. The microstrip line is designed on the front side of the PCB with a right angle for all the slots to make it easy to mount the slots and the microstrip with a monolithic microwave integrated circuit (MMIC). The proposed antenna is designed and simulated using an electromagnetic simulator based on the method of moment (MoM). For the validation the antenna was fabricated on a double-sided substrate material that was 0.79 mm thick with an area of 45 × 40 mm2. The simulation and measurement results show that the antenna has good input-impedance bandwidths of S11 less than or equal to -10 dB at the five operating frequencies of 3.5, 4.1, 5, 6.4, and 6.8 GHz and that extends in the range 2 to 7.5 GHz. The measurements were found to be in good agreement with the simulation results for S11 and provide a stable radiation pattern. |
| Author(s): | N. H. Gad, M. Vidmar |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2710 KB |
| Title: | Design of Reconfigurable Antenna Feeding Network Using Coupled-line Switch for 5G Millimeter-wave Communication System |
| Abstract: | In this paper, a reconfigurable antenna feeding network using coupled line switches for 5G communication system is presented. Two quarter-wave impedance transformers were integrated to support TDD operation and a single stage coupled line filter was used as a DC block for RF switches instead of using conventional surface mounting components. Design equations and theoretical analysis for the proposed reconfigurable antenna feeding network are also presented. To demonstrate the performance of the proposed reconfigurable antenna feeding system for MIMO, two monopole antennas were integrated orthogonally to the designed feeding network. Vertical or horizontal polarization was successfully formed and the radiation pattern can be selectable by manipulating the switches. |
| Author(s): | S. Kim, J. Kim |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2301 KB |
| Title: | Multi-Beamformer with Adjustable Gain: Projection Approach |
| Abstract: | In this paper, a new multi-beam forming approach is presented. First, we divide the steering vectors into two parts. The first part is the beam vector space. The second part is the side lobe vector space. Given that the inner product of two orthogonal vectors is zero, to minimize the gains of the side lobes, the excitation vector of the antenna array elements has to be placed in the orthogonal projection matrix of the side lobe vector space. Then, we obtain a vector by linearly combining the beam vectors and orthogonally projecting the combined vector into the orthogonal projection matrix of the side lobe vector space, and this projection vector is just the solution of the excitation vector of the antenna array elements. Since the combined vector is the linear combination of the beam vectors, we can control the beam gain by adjusting the linear combination coefficients. This new method can be easily used to form multi-beams and adjust each beam gain. The results of simulations show, that the new method acts effectively and efficiently. |
| Author(s): | J. Chen, Y. Yin |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1769 KB |
| Title: | A Novel Design of Wideband Koch like Sided Sierpinski Square Carpet Multifractal Antenna |
| Abstract: | This paper reveals Koch Like Sided Sierpinski Square Carpet Multifractal Antenna (KLSSSCMA) having wideband features and comprises a new hybrid geometry using Sierpinski carpet and Koch curve geometries. The antenna is designed using square patch having dimensions 29.4 mm × 29.4 mm over Roger RT/Duroid substrate having height equal to 3.18 mm and dimensions 48.48 mm × 48.48 mm. The proposed antenna is analyzed and simulated using FEM (Finite Element Method) based Ansoft HFSSTM v.13 software successfully up to fourth iteration. Simulation results show that KLSSSCMA has wideband characteristics from 2 to 8 GHz that covers S and C bands for WiMAX, WPAN, WLAN and Wi-Fi applications. The projected antenna is capable of achieving a good impedance bandwidth with S11 less than -9 dB over the whole range of BW and also exhibits almost stable radiation patterns. |
| Author(s): | A. K. Sidhu, J. S. Sivia |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1802 KB |
| Title: | Review of RF Cloaking Techniques for Antenna Applications |
| Abstract: | This paper reviews the background phenomenon of various cloaking techniques such as transformation optics, transmission line network, microwave network cloak, scattering cancellation techniques in the applications of antenna field particularly in hiding the obstacle from the electromagnetic source and reducing the mutual coupling between two antennas that was placed closed to each other. Cloaking at multiple frequencies in each cloaking techniques are also compared. The comparative study showed that the scattering cancellation technique based on aperiodic Frequency Selective Surfaces (FSS) structure will dominate the electromagnetic cloaking field in near future. |
| Author(s): | N. Kumutha, K. Hariharan, N. Amutha, B. Manimegalai |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1886 KB |
| Title: | Analysis, Modeling, and Measurement of Shielding Effectiveness for a Cylindrical Waveguide with a Hexagonal Insert Structure |
| Abstract: | A theoretical model is presented for the shielding effectiveness of a waveguide containing an insert consisting of several smaller hexagonal or “honeycomb”-shaped waveguides. FEKO, an electromagnetic modeling software package, is used to create computer-aided design (CAD) models of physical waveguides, and to find solutions for the TE11 mode of propagation for each model using the Finite Element Method (FEM). S-parameters are used to characterize the shielding effectiveness of the waveguide models through simulation in FEKO and measurement of waveguide samples in the laboratory. The results obtained by each method are compared and discussed. |
| Author(s): | S. W. Faust, D. N. Aloi |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2451 KB |
| Title: | Voltage Parameter Identification of AC Overhead Transmission Lines by Using Measured Electric Field Data |
| Abstract: | With the development of smart power grids, the demand for real-time voltage monitoring along overhead transmission lines (OTLs) has been growing. However, the existing voltage measurement of OTLs by using potential transformers involves formidable difficulties. This study proposes a non-contact measurement method in which the voltages on AC OTLs are inversely calculated on the basis of the measured data of the power frequency electric field under OTLs. To improve the accuracy and stability of the inverse calculation, an accurate mathematical model and modified inverse algorithms are investigated and then a set of feasible approaches are proposed. First, considering an overhead conductor’s actual physical form and the meteorological conditions of its operating environment, a 3-D catenary model is built, and the mathematical relations between 3-D electric fields and the voltages on OTLs are identified. Second, the improved particle swarm algorithm is used to search the optimal measurement positions of the electric field to improve the ill-posedness of inverse problems. Third, the iterative Tikhonov regularization method, in which the number of iterations is considered as the variable, is adopted to further improve the ill-posedness of inverse problems and reduce the susceptibility of regular solutions to regularization parameter alpha. Fourth, root mean square values and phase parameters of AC voltages are identified from the sinusoidal fitting curves obtained by the real-time inverse calculation. Results of the simulation and experiment examples show that inverse solutions of high precision can be obtained under the condition with relatively high errors of electric field measurement. Moreover, the advantages of the proposed inversion method, such as fast computing speed and good stability, are demonstrated. |
| Author(s): | D. Xiao, Q. Zheng, Y. Xie, Q. Ma, Z. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1840 KB |
| Title: | Design and Analysis of a Novel Variable Frequency Transformer |
| Abstract: | Cross-regional power supply and regional power grid interconnection is the future development of the power grid. At present, AC and DC asynchronous interconnection methods have disadvantages of complicated control and poor system stability. A grid interconnection solution based on variable frequency transformer (VFT) is a possible solution. Based on the introduction of the basic structure and operation principles of VFT, this paper presents a new structure in which a VFT and a drive motor share a core of electrical steel. The new structure VFT is modeled and analyzed by finite element analysis. Through the analysis of the air gap magnetic field of the VFT, the coupling analysis and operating characteristics analysis of the power winding and the control winding verify the design. |
| Author(s): | X. Deng, N. Liu, Y. Sun, Q. Guo, M. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2256 KB |
| Title: | Performance Analysis of Outer Rotor Wound Field Flux Switching Machine for Direct Drive Application |
| Abstract: | One of the premium in-wheel applications is direct drive, evolving enormously for HEV’s. An alternative and lot of research especially on the outer rotor field excitation flux switching machine is required to overcome the problems like demagnetization and high cost of rare earth magnetic material used in interior permanent magnet synchronous machine (IPMSM). Salient rotor pole and non-overlapping winding embedded in electrical machine design possess some pertinent features such as; reduce copper losses, low-cost, and usage in high speed applications. Therefore, this paper emphasizes on the design of three-phase outer rotor wound field FSM employing optimization, performance analysis and MEC models of proposed 12-slot/13-pole FSM corresponding to different rotor positions are combined as GRN and are solved utilizing incidence matrix methodology using MATLAB. Moreover, FSM flux behavior, no-load, and load analysis were examined using JMAG software and based on FEA. Results obtained from GRN methodology and corresponding FEA results close resemblance with and errors less than ~1.2%, hence validating accuracy of GRN methodology. The proposed design for hybrid electric vehicle torque characteristic is compared with existing IPMSM and 6-slot/7-pole non-overlapping stator wound flux switching machine (NSWFS). |
| Author(s): | N. Ahmad, F. Khan, N. Ullah, M. Z. Ahmad |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2430 KB |
| Title: | Comparison of Analytical Methodologies for Analysis of Single Sided Linear Permanent Magnet Flux Switching Machine: No-Load Operation |
| Abstract: | A novel single sided Linear Permanent Magnet Flux Switching Machine (LPMFSM) with twelve mover slots and fourteen stator teeth (12/14), having two additional end teeth on both sides of mover is presented. Presence of both Armature Winding (AW) and Permanent Magnet (PM) on mover structure results in completely passive, robust, and low cost stator. While, demerits such as less slot area, complex flux density distribution, and magnetic saturation caused by passive stator demands to be analyzed by time consuming and computationally complex numerical modelling techniques, i.e., Finite Element (FE) Analysis, requiring expensive hardware/software. In this paper, two cost effective and fast response analytical techniques are developed to analyze no-load performance of LPMFSM. Two no-load characteristics, i.e., open-circuit flux linkage and detent force are analyzed by Equivalent Magnetic Circuit (termed as analytical technique No. 1) and Lumped Parameter Equivalent Magnetic Circuit (termed as analytical technique No. 2). Both analytical methodologies are compared and validated with corresponding globally accepted FE Analysis. Analysis revealed that LPEMC is better approach for initial design of LPMFSM. |
| Author(s): | N. Ullah, M. K. Khan, F. Khan, A. Basit, W. Ullah, T. Ahmad, N. Ahmad |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2122 KB |
| Title: | The 2D Type-3 Non-Uniform FFT in CUDA |
| Abstract: | We present the parallel implementation on Graphics Processing Units (GPUs) of a type-3 Non-Uniform FFT (NUFFT) approach, namely, of a NUFFT for which data and results are located at irregular points. The performance of the algorithm is assessed against that of a parallel implementation of the same algorithm on multi-core CPUs using OpenMP directives. |
| Author(s): | A. Capozzoli, C. Curcio, A. Liseno, J. Piccinotti |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 8 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1871 KB |