ACES Publication Search
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| Title: | ACES Journal August 2013 Full Issue |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 13262 KB |
| Title: | ACES Journal August 2013 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 39 KB |
| Title: | Time Domain Analysis of Ultra-Wide Band Signals from Buried Objects Under Flat and Slightly Rough Surfaces |
| Abstract: | The analysis of transient scattering for TMz (horizontally) polarization from a cylindrical perfectly conducting (PEC) object buried in a lossy medium is considered. Flat and slightly surface cases are considered for the dielectric halfspace. Our previous work using a decomposition method solution in frequency domain of TMz polarization is utilized to solve this scattering problem. Then, an inverse Fourier transform is used to get the time domain signals. Timing analysis is done by calculating the travelling time of reflected signals in the possible paths. Then, multiple reflections are identified using these travelling times. Finally, the results from the flat and slightly rough surface profiles are used to compare the effects of multipath propagation. |
| Author(s): | S. MakalYucedag, A. Kizilay |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 519 KB |
| Title: | Efficient Volume Reduction of Optimally Designed Pyramidal Log-Periodic Antennas via Meander Elements |
| Abstract: | A class of volume-optimized pyramidal log-periodic antennas (PLPAs) with an adjustable ultra wideband performance is introduced in this paper. To this aim, a parametric analysis is initially conducted to decrease the total size of the prototype Euclidean-toothed PLPA. The new structures are based on the concept of meander curves, which leads to efficient substitutes of the conventional device with drastically reduced dimensions, but equivalent behavior. For the design procedure, the radiation features of all antennas are accurately evaluated via a 3-D finite-difference time-domain (FDTD) algorithm. Extensive investigation reveals that the prior volume-confinement method and the proposed radiators can provide very compact setups for a variety of modern communication systems. |
| Author(s): | S. A. Amanatiadis, A. X. Lalas, N. V. Kantartzis, T. D. Tsiboukis |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1078 KB |
| Title: | Solving Inverse Scattering for a Partially Immersed Metallic Cylinder Using Steady-State Genetic Algorithm and Asynchronous Particle Swarm Optimization by TE waves |
| Abstract: | The transverse electric (TE) polarization for shape reconstruction of a metallic cylinder by asynchronous particle swarm optimization (APSO) and steady-state genetic algorithm (SSGA) is presented. These approaches are applied to two-dimensional configurations. After an integral formulation, a discretization using the method of moment (MoM) is applied. Considering that the microwave imaging is recast as a nonlinear optimization problem, an objective function is defined by the norm of a difference between the measured scattered electric field and that calculated for an estimated shape of metallic cylinder. Thus, the shape of metallic cylinder can be obtained by minimizing the objective function. In order to solve this inverse scattering problem, two techniques are employed. The first is asynchronous particle swarm optimization. The second is steady-state genetic algorithm. Both techniques have been tested in the case of simulated measurements contaminated by additive white Gaussian noise. Numerical results indicate that the asynchronous particle swarm optimization outperforms steady-state genetic algorithm in terms of reconstruction accuracy and convergence speed. |
| Author(s): | C. L. Li, C. H. Sun, C. C. Chiu, L. F. Tuen |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 276 KB |
| Title: | A Method-of-Moments Model for Determination of Radiated Magnetic Field from Switch-Mode Power Supplies Components using Near-Field Measurement Data |
| Abstract: | Electromagnetic interference due to switching-mode power supplies (SMPSs) is a great concern for the designers of electrical and electronic equipment. In this paper, we propose a method-of-moments model for efficient determination of radiated magnetic field due to SMPSs mounted on printed circuit boards (PCBs). This model involves three stages. First, the magnetic field distribution on a given rectangular plan in the vicinity of the board is measured. The measured data are then used to identify the equivalent source currents on the surface of the radiating board by the method-of-moments. Having determined the radiating sources, the magnetic field distribution at a desired distance from the PCB can be computed. The main feature of the proposed model is its direct approach for reconstruction of the radiating current sources, which makes it much faster than the conventional techniques, involving heuristic optimization algorithms. The validity of the proposed technique is demonstrated by comparing the actual and predicted far-field magnetic field radiations due to a small electrical loop, a high frequency inductor as a typical radiating magnetic field component of SMPSs, and a microstrip transmission line, which simulating conduction paths on the PCB. |
| Author(s): | S. M. M. Mirtalaei, S. H. H. Sadeghi, R. Moini |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 498 KB |
| Title: | Convolutional Perfectly Matched Layer (CPML) for the Pseudospectral Time-Domain (PSTD) Method |
| Abstract: | In this paper, a perfectly matched layer (PML) medium with complex frequency shifted (CFS) constitutive parameters is introduced into the two-dimensional pseudospectral time-domain (PSTD) algorithm. The absorbing performance and computational efficiency of the method are illustrated by comparing with the PML method. It shows that no matter what spatial discretization is used, the reflection relative error of convolutional perfectly matched layer (CPML) is almost the same as that of the PML method. The total flops counts of the PSTD-CPML method are reduced from 49 to 34 compared with that of the PSTDPML method. This corresponds to an efficiency gain of 1.44 in flops count reduction for the PSTD-CPML method. |
| Author(s): | J. Chen, J. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 166 KB |
| Title: | Design and Improvement of Compact Half-Wavelength Band Pass Filter Employing Overlapped Slotted Ground Structure (SGS) and Multilayer Technique |
| Abstract: | This paper deals with a compact Chebyschev 3rd hairpin band pass filter design, using the Richards-Kuroda transformation method. Afterwards, a combination of slotted ground structure (SGS) and multilayer technique is applied. Filters using quarter-wavelength steppedimpedance resonator without and with SGS technique are investigated. Finally, two band pass filters are designed, simulated, and partially measured. A compact SGS band pass filter operated at 4.35 GHz is demonstrated. The proposed band pass filter has low insertion loss, high rejection in both the stop bands and a compact size of (20 × 23) mm2 (0.075 ?g × 0.058 ?g) with a guide wavelength ?g = 0.359 m. Additionally, the structure has generated two transmission zeros on both sides of the pass band at 3.1 GHz and 4.9 GHz. The simulated results as well as the experimental results are satisfactory with the filter requirements. The introduced structure can be a good alternative to a conventional parallel-coupled half wavelength, as well as quarter-wavelength stepped-impedance resonator band pass filter. |
| Author(s): | A. Boutejdar, A. Darwish, A. Omar |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 757 KB |
| Title: | A Pattern Reconfigurable Antenna Based on TM10 and TM02 Modes of Rectangular Patch |
| Abstract: | A pattern reconfigurable rectangular microstrip antenna is reported in this paper. A broadside radiation pattern and a conical pattern are obtained when it alternatively operates in the TM10 mode and TM02 mode of the rectangular patch. Suitable patch size parameters and feeding positions are selected so that these two modes share the same operating frequency. Two PIN diodes are employed to switch the operating modes. The configuration of the antenna is simple, which consists of a rectangular patch and a reconfigurable feeding network to excite expected mode. The feature of the proposed antenna is that the design method is explicit, based on different resonant modes with different radiation characteristics, and can be used to design other types of reconfigurable antennas. |
| Author(s): | H. Y. Huang, B. Z. Wang, X. Ding, W. Shao |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 6877 KB |
| Title: | A Simple Design of UWB Small Microstrip Slot Antenna with Band-Notched Performance by using a T-Shaped Slit and a Pair of UShaped Conductor-Backed Plane |
| Abstract: | In this paper, a simple and compact ultra wideband printed slot antenna with bandnotch performance is designed and manufactured. In order to increase the impedance bandwidth of the square slot antenna, we use two U-shaped parasitic structures inside the rectangular slot on the ground plane that with this structure UWB frequency range can be achieved. Additionally, by using a T-shaped slit on the ground plane, a frequency notched band performance has been obtained. The designed antenna has a small size of 20×20 mm while showing the radiation performance in the frequency band of 3.05 GHz to over 12 GHz with a band rejection performance in the frequency band of 5.1 GHz to 6.05 GHz. |
| Author(s): | M. Ojaroudi, N. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 530 KB |
| Title: | Design of a Two Bands Circularly Polarized Square Slot Antenna for UWB Application |
| Abstract: | A novel ultra-wideband slot antenna fed by a coplanar waveguide (CPW) is presented and experimentally investigated. The proposed antenna has capability of both the circular polarization and ultra wideband (UWB) performance. The designed antenna has a size of 40 × 40 × 0.8 mm3. The experimental results show that the antenna has an impedance bandwidth of 142 % and axial-ratio (AR) bandwidths of 35 % for the lower band and 22.6 % for the upper band. |
| Author(s): | N. Felegari, H. R. Dalili Oskouei, M. Akbari, M. Mighani |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 481 KB |
| Title: | Square Monopole Antenna with Band-Notched Characteristic for UWB Communications |
| Abstract: | In this paper, a novel ultra wideband monopole antenna with frequency band-stop performance is designed and manufactured. The proposed antenna consists of a square radiating patch, and a ground plane with a cross-shaped slit and an inverted ?-shaped conductor-backed plane. The cross-shaped slit, increases the bandwidth that provides a wide usable fractional bandwidth of more than 125 % (2.86 GHz – 12.91 GHz). In order to create band-notched function we use an inverted ?-shaped parasitic structure in the ground plane, a frequency notch band of 5.11 GHz – 6.02 GHz has been achieved. Good VSWR and radiation pattern characteristics are obtained in the frequency band of interest. Simulated and measured results are presented to validate the usefulness of the proposed antenna structure for UWB applications. |
| Author(s): | M. Ojaroudi, N. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 463 KB |
| Title: | A Planar UWB Monopole Antenna with On-Ground Slot Band-Notch Performance |
| Abstract: | A planar monopole antenna with variable frequency band-notch characteristic for ultra wideband applications is presented. The proposed antenna consists of a truncated ground plane and a radiating rectangular patch. By employing two L-shaped strips on the top edge of the ground plane, the ultra wideband property is achieved. Electromagnetic interference (EMI) from IEEE 802.11a can be avoided for a wideband antenna with a stop-band. For a notched frequency band, two L-shaped slits are embedded on the ground plane. The designed antenna has a stopband of 5 GHz to 5.9 GHz while maintaining wideband performance from 3.1 GHz to 10.6 GHz for VSWR < 2. |
| Author(s): | M. Mirmozafari, Ch. Ghobadi, H. Mirhedayati, A. Rezaee |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 815 KB |
| Title: | Compact Dual Band-Reject Monopole Antenna for UWB Applications |
| Abstract: | In this letter, a compact planar ultrawideband (UWB) monopole antenna with excellent band-rejection characteristics is proposed for UWB communications applications. To achieve band-rejection filter property at the WiFi / WiMAX bands, two different types of slots: sloped open-ended Z-shaped slot and split rectangle ring slot on radiation patch, are introduced to form two stop-bands. The measured and simulated results show that the band-notched characteristics not only bring good rejection frequency, but also improved the skirt area in the band-notched frequency, and the proposed antenna has nearly omni-directional radiation pattern, moderate gain, and low cross-polarization level, which is suitable for UWB communication applications. |
| Author(s): | P. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 384 KB |
| Title: | A New Design of Printed Monopole Antenna with Multi-Resonance Characteristics for DCS/WLAN/WiMAX Applications |
| Abstract: | In this paper, a new printed monopole antenna is presented for simultaneously satisfying DCS, wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) applications. The operating frequencies of the proposed antenna are 1.8 GHz, which covers DCS operations, 2.4/5.2/5.8 GHz for WLAN system and 2.5/3.5/5.5 GHz for WiMAX system. The desired first and second resonant frequencies are obtained by adjusting the length of the L-shaped slits. Also by cutting an inverted ?- shaped slot in the radiating patch; multi band performance can be produced. Prototypes of the proposed antenna have been constructed and studied experimentally. The measured results show good agreement with the numerical prediction and good multiband operation. |
| Author(s): | M. Ojaroudi, N. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 464 KB |
| Title: | Magnetic Charge and Magnetic Field Distributions in Ferromagnetic Pipe |
| Abstract: | This paper proposes the equivalent magnetic charge (EMC) method, to analyze the magnetic field presented in ferromagnetic pipe. Distributions of the magnetic charge density on pipes’ surface are calculated, and the magnetic field on several measurement lines is predicted using numerical calculation with several different directions of magnetization. The correctness of the analysis results is then validated by the comparison between the results of the ANSOFT and measurement of the magnetic field inside several actual pipes. With the EMC method, it is of great interest to found that when the magnetization direction changes, the radial and axial magnetic field components inside the pipe will shift accordingly. Moreover, the variation law of magnetic field along the axial retains substantially unaltered, and the magnetic field distribution in the pipe is obviously symmetrical with a plurality of extreme points. As a result, the magnetic field distributes evenly if the pipe is long enough. |
| Author(s): | H. Xinjing, C. Shili, G. Shixu, Z. Wei, J. Shijiu |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1423 KB |
| Title: | Shore to Ship Steerable Electromagnetic Beam System Based Ship Communication and Navigation |
| Abstract: | Electromagnetic waves prove to be a common ground for producing integrated systems that use a single transmitter, receiver, and computer system to perform communication, navigation, and surveillance activities. A steerable beam array antenna serves to communicate from shore to a moving ship close to the harbor. In this paper, the communication system parameters are used also to navigate the ship to a predetermined harbor dock. Knowledge of the electromagnetic radiation pattern of the beam steering array antenna, the position of the ship, and the predetermined trajectory for the ship are used to create an on-line navigational system that is driven by the received communication signal power. The discrepancies in signal power measured and the expected received power are used as an indicator that the ship is not properly aligned to the transmitter beam peak point. This discrepancy that is obtained by a signal processor is used to reset the rudder angle through a PID controller. It is shown that this system successfully keeps the ship within the border lines of the trajectory that had been marked out to guide the ship to its harbor dock. Moreover, the antenna electromagnetic beam, like a torch, moves a step ahead of the ship along the trajectory, allowing for automatic navigation of the ship as the ship’s rudder is activated to move the ship to keep within the antenna beam’s half-power points. |
| Author(s): | P. R. P. Hoole, S. T. Ong, S. R. H. Hoole |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 8 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 453 KB |