ACES Publication Search
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| Title: | ACES Journal October 2016 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2103 KB |
| Title: | ACES Journal October 2016 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 39 KB |
| Title: | ACES Journal October 2016 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 14134 KB |
| Title: | Numerical Simulation of High Electron Mobility Transistors based on the Spectral Element Method |
| Abstract: | The spectral element method (SEM) is implemented for the numerical simulation of high electron mobility transistors (HEMTs) through a selfconsistent solution of the Schrödinger-Poisson equations. The electron conduction band structure and electron density distribution are calculated and plotted, and results compared to those based on methods utilizing a finite-difference approach. Simulation accuracy and efficiency are analyzed and compared with traditional finite difference method (FDM). DC current-voltage (I-V) characteristics for the HEMT structure are simulated, based on a quasi-2D current model. The SEM approach offers advantages in speed and efficiency over FDM, while yielding results which conform well to reported experimental results. These advantages are particularly important for compound heterojunction devices with complex material profiles, for which FDM methods may be inefficient and computationally slow. |
| Author(s): | F. Li, Q. H. Liu, D. P. Klemer |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1669 KB |
| Title: | An Efficient ACA Solution for Electromagnetic Scattering from Discrete Body of Revolution |
| Abstract: | Discrete body of revolution (DBoR) enhanced method of moments (MoM) is a specialized technique to analyze electromagnetic scattering from the object with discrete cylindrical periodicity. By exploiting the block circulant property of the impedance matrix of MoM, both filling time and storage requirement for the matrix are reduced. The matrix-vector product can be further accelerated by using the fast Fourier transform (FFT) technique. However, the matrix filling time and memory requirement of DBoR-FFT are the same as those of DBoR-MoM, which are still expensive when the number of unknowns in each sector becomes larger. Meanwhile, the DBoR-FFT scheme works inefficiently for the small number of periodic sectors. In this paper, the adaptive cross approximation (ACA) technique is employed to enhance the DBoR-MoM. Numerical examples are given to demonstrate the efficiency of the proposed method. |
| Author(s): | Z. H. Fan, Z. He, R. S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1452 KB |
| Title: | Electromagnetic Scattering from a PEMC Circular Cylinder Coated by Topological Insulator (TI) |
| Abstract: | Scattering of electromagnetic plane wave from a perfect electromagnetic conducting (PEMC) cylinder coated with a topological insulating (TI) material has been presented. The core (PEMC) and cladding material (TI) produce co- and cross-polarized components of electromagnetic field in response to the incident plane wave for a given polarization (TE or TM). When the value of ? is made zero, TI material becomes ordinary dielectric and the results of PEMC coated with TI with ? = 0 (dielectric material) have been compared with the previously published literature and are found in good agreement. When the coating is removed, same results as that of isolated PEMC circular cylinder have also been reproduced. |
| Author(s): | A. Shahzad, A. Illahi, S. Ahmed, A. Hussain, Q. A. Naqvi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1819 KB |
| Title: | Nonlinear Analysis and Performance Improvement of Amplifying Aperture Coupled Reflectarray Antenna |
| Abstract: | Amplifying reflectarray antenna can be used to increase the overall gain of the antenna in large distance communication systems. However, amplifying reflectarray antenna may become nonlinear in some incident powers which may lead to performance degradation. In this paper nonlinear behavior of an amplifying reflectarray antenna is studied and a new method is proposed to improve the performance of the antenna. Nonlinear analysis of the active unit cell is performed using harmonic balance method considering nonlinear model of the amplifier. Then, the effect of nonlinear element in radiation pattern of the antenna is studied. Aperture coupled patch structure is used to analyze amplifying unit cell. Finally, an amplifying reflectarray antenna considering nonlinear behavior of the active elements is designed and the proposed balanced amplifier structure is used to improve performance of the amplifying antenna. |
| Author(s): | I. Aryanian, A. Abdipour, G. Moradi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1502 KB |
| Title: | Parameterized Model Order Reduction for Efficient Time and Frequency Domain Global Sensitivity Analysis of PEEC Circuits |
| Abstract: | This paper presents a new parameter- ized model order reduction technique to efficiently perform global time- and frequency-domain sensitiv- ity analysis of electromagnetic systems over the de- sign space of interest. The partial element equivalent circuit (PEEC) method is adopted to build the elec- tromagnetic system model at a set of initial samples in the design space. The block Laguerre-SVD algo- rithm is proposed to reduce the size of the original equations of the PEEC-based equivalent circuit along with those describing the port voltage and current sensitivities. Then, a multivariate cubic spline in- terpolation method is used to build a parameterized compact model of port voltages and currents along with their corresponding sensitivities over the entire design space of interest. Finally, two numerical exam- ples are presented, which con rm the accuracy and efficiency of the proposed method. |
| Author(s): | L. De Camillis, G. Antonini, F. Ferranti |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 4286 KB |
| Title: | Finite Difference Analysis of an Open-Ended, Coaxial Sensor Made of Semi- Rigid Coaxial Cable for Determination of Moisture in Tenera Oil Palm Fruit |
| Abstract: | In this paper, the use of the Finite Difference Method (FDM) is proposed to determine the reflection coefficient of an open-ended coaxial sensor for determining the moisture content of oil palm fruit. Semirigid open-ended coaxial sensor is used in conjunction with Vector Network Analyzer for reflection coefficient measurement of oil palm fruit. Moisture content in oil palm fruit determine optimum harvest time of oil palm fruit. Finite difference method is then used to simulate measured reflection coefficient due to different moisture contents in oil palm fruit at various stages of ripeness. The FDM results were found to be in good agreement with measured data when compared with the quasi-static and capacitance model. Overall, the mean errors in magnitude and phase for the FDM were 0.03 and 3.70°, respectively. |
| Author(s): | E. M. Cheng, Z. Abbas, M. F. AbdulMalek, K. Y. Lee, K. Y. You, S. F. Khor, J. Hassan, H. Zainuddin |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1801 KB |
| Title: | Design of PSR with Different Feed Configurations and Partition Lens System for Skin Cancer Treatment |
| Abstract: | The Prolate Spheroidal Impulse Radiating Antenna (PSIRA) focuses pulsed radiation in the near field with a small beam width allowing the application of non-invasive skin cancer treatment. In this proposed work, SWB (Slanted Wire Bicone), EPH (Elliptical Profile Horn), TSVS (Tapered Slot Vivaldi Shape) and Tapered Arm Conical Plate (TACP) feed antenna configurations for Prolate Spheroidal Reflector (PSR) are explored to enhance the spatial resolution on biological target. The feed antenna is placed at the first focal point and the target is located at the second focal point of the PSR. Next, the resolution of focused electric field on the target is enhanced by using near field focusing lens. A 3 layer partition lens system is placed before the target to reduce the spot size of the focused field on the target. The delivery of subnanosecond pulses using reflector in conjunction with and without partition lens system on the biological target is compared for all feed antenna configurations. Tapered Arm Conical Plate (TACP) fed PSR with the 3 layer partition lens system greatly reduces the spot size to 0.5 cm along lateral direction and 1 cm along axial direction. The enhancement in spatial resolution is much favorable to reduce the damage of healthy tissues during cancer treatment. |
| Author(s): | P. Arockiasamy, S. Mohan |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2364 KB |
| Title: | Design, Simulation and Fabrication of a Wide Bandwidth Envelope Tracking Power Amplifier |
| Abstract: | In this paper an envelope tracking power amplifier is designed and implemented using MRF6S27015N MOTOROLA transistor in LDMOS technology. First, the amplifier is designed using load pull simulation and its parameters are optimized to increase the power added efficiency. Next, envelope detector and envelope amplifier are designed and simulated and finally ET is applied to the amplifier which results in more than 50% of PAE in a wide range of input power with bandwidth of 200 MHz. Envelope detector circuit is fabricated using schotkey diode and envelope amplifier is manufactured using a mosfet, an op amp, and a comparator. |
| Author(s): | I. Aryanian, A. Abdipour, A. Mohammadi |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1577 KB |
| Title: | Analysis of Control Variables to Maximize Output Power for Switched Reluctance Generators in Single Pulse Mode Operation |
| Abstract: | This paper presents an analytical modeling method of optimal control variables to maximize the output power for switched reluctance generators (SRGs) in single pulse mode operation. A method to obtain the phase current equation used to determine the optimal control variables is proposed. The phase current equation is derived from the phase voltage equation in combination with the inductance model. The inductance model proposed in this paper is applied from the flux linkage function. The characteristics of the phase current and the energy conversion relations are analyzed to determine the optimal phase current shape. The analytical results indicate that the optimal shape can be generated when the SRG is controlled with the optimal control variables. The optimal shape is used for analysis based on the phase current equation to determine the optimal control variables. An 8/6 SRG experimental setup is used to validate the proposed method. The optimal control variables obtained from the proposed method are used to control the SRG. Based on the experimental results, the SRG can produce the maximum output power. |
| Author(s): | P. Thongprasri, S. Kittiratsatcha |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2354 KB |
| Title: | Electromagnetic Coupling Analysis of Transient Excitations of Rectangular Cavity through Slot using TD-EFIE with Laguerre Polynomials as Temporal Basis Functions |
| Abstract: | This paper presents an electromagnetic coupling analysis of transient waves excited a rectangular cavity containing an interior scatterer coupled to an external scatterer through a slot. Based on the equivalence principle, time domain integral equations are established by enforcing the boundary conditions on the internal and external scatterers, the slot and the cavity walls. The method of moments is applied in space and time domains to solve the developed system of integral equations. The unknown coefficients of the electric and magnetic currents are approximated by the triangular piecewise functions associated with Dirac function as space basis. To obtain accurate and stable solutions, the Laguerre functions are used as temporal basis. Numerical results involving the coupling effects between the cavity components are investigated. The numerical results are found to be in good agreement with EM theory and literature. |
| Author(s): | D. Omri, T. Aguili |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1645 KB |
| Title: | Ultra-Wideband Balanced Bandpass Filters Based on Transversal Signal- Interference Concepts |
| Abstract: | Two ultra-wideband balanced bandpass filters based on transversal signal-interference concepts are proposed in this paper. By employing the two structures: microstrip/slotline transition, and quarter-wavelength shorted coupler lines, 180° phase shift can be easily implemented for each design. In addition, due to the different transmission paths, wideband common mode rejection and differential mode transmission bandwidth can be achieved. Two balanced filters centered at 3 GHz are calculated, fabricated and measured successfully. For the differential mode, the 3-dB fractional bandwidths are 102% from 1.47 GHz to 4.53 GHz and 103% from 1.52 GHz to 4.61 GHz, respectively, and the return loss are both greater than 20 dB. For the common mode, signals are suppressed below -20 dB and -15 dB over the whole frequency band. |
| Author(s): | C. Zhao, W. Feng, Y. Li, W. Che |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1803 KB |
| Title: | Novel Pentagonal Dual-Mode Filters with Adjustable Transmission Zeros |
| Abstract: | Novel compact pentagonal dual-mode filters with open stub is presented. The field patterns of this type of resonators are investigated using full-wave electromagnetic simulations. The technique of utilizing capacitive and inductive source-load coupling to improve the performance of filters is explored. Advantages of using this type of filter are not only its compact size, but also its transmission zeros that can be independently controlled. Then, two dual-mode bandpass filters are designed, fabricated and tested to validate the design concept. Both simulated and measured results are presented. |
| Author(s): | Z. Zhu, S. Liang, C. Wei |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1616 KB |
| Title: | Miniaturized Microstrip Suppressing Cell with Wide Stopband |
| Abstract: | In this paper, based on simple stepped impedance structures a methodology is followed to design a very compact size lowpass filter (LPF) as a suppressing cell. The proposed suppressing cell consists of stepped impedance ladder-type resonators, which provides a wide stopband by creating the transmission zeros to its frequency response. The proposed suppressing cell has clear advantages like low insertion loss in the passband and suitable roll-off. The designed LPF is fabricated on a microstrip layout and tested. The measured results highlight the efficiency of the filter and have a good agreement with the simulated results. With mentioned expression, the fabricated LPF can be a powerful block as a suppressing cell to implement in the distributed high frequency circuits. |
| Author(s): | M. Hayati, F. Shama, M. Ekhteraei |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1703 KB |
| Title: | A Low-pass Filter with Sharp Transition and Wide Stop-band Designed based on New Metamaterial Transmission Line |
| Abstract: | A low-pass filter (LPF) with sharp and wide stop-band was designed based on new metamaterial transmission line. Its characteristics were investigated, and found to have good low-pass performances with only one cell. The simulated results of the LPF are in good agreements with the measured results. Two measured transmission poles were observed at 1.35 GHz and 2.13 GHz. The measured 3 dB cut-off frequency is 2.38 GHz and the transmission attenuate to -20 dB at 2.62 GHz, thus, a 240 MHz width sharp transition was achieved. The measured attenuation of the stop-band is larger than 25 dB with two transmission zeros at 2.79 GHz and 5.19 GHz. A wide stop-band over 10 GHz was observed. Therefore, the proposed LPF is a good candidate for RF systems. |
| Author(s): | L. Peng, Y. J. Qiu, X. Jiang, C. L. Ruan |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 2044 KB |
| Title: | High Selectivity Balanced Filters Based on Transversal Signal-interaction Concepts |
| Abstract: | Two novel high selectivity balanced filters based on transversal signal-interaction concepts with wideband common mode suppression are proposed in this paper. Four and six transmission zeros near each passband are realized to improve the selectivity for the differential mode. In addition, the common mode can be suppressed with insertion loss greater than 15 dB over a wide frequency band. Two prototypes (?r = 2.65, h = 0.5 mm, tan ? = 0.003) with 3-dB fractional bandwidths of 31.3% and 32% for the differential mode with upper stopband greater than 18 dB are designed and fabricated. Good agreements can be observed between measured results and theoretical expectations. |
| Author(s): | W. Feng, M. Hong, W. Che |
| File Type: | Journal Paper |
| Issue: | Volume: 31 Number: 10 Year: 2016 |
| Download Link: | Click here to download PDF File Size: 1970 KB |