ACES Publication Search
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| Title: | ACES Journal June 2013 Full Issue |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 6230 KB |
| Title: | ACES Journal June 2013 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 613 KB |
| Title: | Equivalent Circuit Models for Propagation Analysis of In-Building Power line Communications Systems |
| Abstract: | In-building power line transmission measurements show potential for low attenuation propagation above 30 MHz. These measurements show that frequency bands can exist having low or minimum attenuation above 100 MHz. A simple high-frequency propagation model for analysis of in-building communications up to 900 MHz, which can be implemented using a commercial circuit simulator, is described. This physics-based model is extracted using broadband data from both time- and frequency-domain network transmission (S21) measurements. The novelty of this modeling approach is that different propagation modes such as electromagnetic coupling, waveguide propagation through the wiring conduit, and fading are included. An RF circuit model in a simulator environment is useful for analyzing a wide range of communication problems at the circuit, subsystem, and system levels. |
| Author(s): | A. Hakimi, G. A. Ellis |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 750 KB |
| Title: | Discontinuous Galerkin Time Domain Method for Scattering Analysis of Air-Inlets |
| Abstract: | In this paper, a high-order three dimensional (3-D) discontinuous Galerkin time domain (DGTD) method has been introduced for the first time for the efficient scattering analysis of air-inlets. This method combines the geometrical versatility of finite element method (FEM) with the explicit time-stepping of finite volume time domain (FVTD) method, thus having the advantages of handling electrically large, arbitrarily shaped, and complex media objects. To validate the capability of this method, the radar cross section (RCS) of three typical air-inlet models have been simulated. The results of the DGTD method agree well with that of the method of moments (MoM), which proves the DGTD method a useful alternative to the traditional methods to solve the scattering problems. |
| Author(s): | S. Gao, M. Lin, Q. Cao |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 389 KB |
| Title: | Analytical Solution of Scattering by a 2D Dielectric Filled Crack in a Ground Plane Coated by a Dielectric Layer: TM Case |
| Abstract: | In this paper, KP method is applied to study the scattering of a 2D loaded crack on a ground plane, coated by a dielectric layer for TM case. For simplicity, the geometry is divided into three regions, whose fields are expressed in terms of Bessel eigen functions. The governing equations involve several infinite summations with infinite number of unknown coefficients. By the use of Weber-Schafheitlin discontinuous integrals, these infinite summations could efficiently be truncated with high numerical accuracy. Boundary conditions are applied to determine unknown coefficients. We employ finite element method (FEM) and convergence analysis to confirm our results. Finally, the influence of coating dielectric layer and filling material is investigated on the scattered field. |
| Author(s): | B. Ghalamkari, A Tavakoli, M. Dehmollaian |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 600 KB |
| Title: | Scattering by a Metallic Sphere Coated with Chiral Metamaterials |
| Abstract: | Co-polarized and cross-polarized electromagnetic scattering of a metallic sphere coated with chiral metamaterials (CMMs) are simulated with Mie series solution. Firstly, based on Bohren’s decomposition technique, electromagnetic fields inside and outside of the sphere are expanded in spherical harmonics vector function. Then, the expanded coefficients are obtained in a suitable form for computation by applying the boundary conditions on the interfaces of all regions. The validity of Mie series solution is shown by computing backward scattering for a ferrite-coated metallic sphere. The effects to bistatic, forward and backward scattering caused by incident wave frequency, media parameters of a metallic sphere coated with CMMs are investigated in details. |
| Author(s): | M. Y. Wang, N. Yang, S. C. Ye, H. L. Li, J. Xu, C. L. Zhong, H. Zheng |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 574 KB |
| Title: | A Novel Wilkinson Power Divider Using Open Stubs for The Suppression of Harmonics |
| Abstract: | In this paper, the design process of a novel Wilkinson power divider is presented. The proposed power divider features a simple structure with open stubs at each port. With slight changes of the dimensions of open stubs, designed power divider can suppress combinations of each two desired order harmonic simultaneously. From the measured results, 45 dB and 43 dB suppression for 3rd and 5th harmonics is obtained, respectively. The proposed power divider has an insertion loss less than 0.1 dB, input return loss better than 31 dB, output return loss better than 51 dB, and better than 43 dB of isolation at 1.65 GHz. |
| Author(s): | M. Hayati, S. Roshani |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 399 KB |
| Title: | A Linear-to-Circular Polarizer Using Split Ring Resonators |
| Abstract: | A transmission polarizer with one layer of splitting ring resonator to realize a linearto- circular polarization rotator is presented. Based on the accurate design of anisotropic metamaterials, high conversion efficiency and 8 % frequency band are achieved. Microwave experiments were performed to realize these ideas successfully and results are in excellent agreement with numerical simulations. |
| Author(s): | J. Chen, A. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 388 KB |
| Title: | Compact Microstrip Lowpass Filter with Wide Stopband and Sharp Roll-off using Triple Radial Stubs Resonator |
| Abstract: | A novel microstrip lowpass filter with good specifications such as sharp cutoff, wide stopband, low insertion loss, and high return loss is proposed. The proposed lowpass filter is realized using triple radial stubs resonator, i.e., three 60o radial stubs and harmonic attenuator, i.e., T shaped cell loaded by the semicircle. The cutoff frequency of the proposed filter is adjusted to 1.39 GHz. The transition band is approximately 0.21 GHZ from 1.39 GHz to 1.6 GHz with corresponding attenuation levels of -3 dB and -20 dB. The stopband with better than -20 dB rejection is from 1.6 GHz to 12.36 GHz, insertion loss in the passband is less than 0.1 dB, return loss is less than -25 dB and the overall size of the filter is 0.0074 ?g2 ( 15 × 12.3 mm2 ). The proposed filter is fabricated and measured. The simulation and measurement results are in good agreement. |
| Author(s): | M. Hayati, H. A. Memari, H. Abbasi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 770 KB |
| Title: | A Microstrip Printed Band-Notched UWB Antenna Using Modified CSRR Structure |
| Abstract: | A compact triple band-notch ultrawideband (UWB) antenna with microstrip-feed is presented. The desired band-notch antenna is achieved by etching a narrowband triple complementary split-ring resonator into the radiating element of an existing UWB antenna. By attenuation of the measured return, the new antenna reduces interference from UWB in the Cband (3.7 GHz - 4.2 GHz) satellite communication systems and wireless local area network (5.15 GHz - 5.35 GHz, 5.725 GHz - 5.825 GHz bands). The built prototypes have a compact size of 25 × 27.9 mm2 including the ground plane. This miniature size also delivers advantageous radiation patterns with good mono-polar characteristics across the UWB band with the gain attenuated within the desired notch bands. The antenna demonstrates omnidirectional and stable radiation patterns across all the relevant bands. Moreover, a prototype of the proposed antenna is fabricated, and the measured results are shown to be in good agreement with the simulated results. |
| Author(s): | D. Jiang, Y. Xu, R. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1268 KB |
| Title: | Disc-Shaped Monopole Antenna with Dual Band-Notched Function for UWB Applications |
| Abstract: | In this paper, we present a novel design of dual band-notched printed monopole antenna for UWB applications. By cutting an anchor-shaped slit in the disc-shaped radiating patch a single frequency band-stop performance can be achieved, also in order to create dual bandnotched function, we use a T-shaped strip protruded inside a rectangular slot in the ground plane that with this design, a dual band-notched operation has been obtained. Simulated and measured results obtained for this antenna show that the proposed monopole antenna offers two notched bands, covering all the 5.2/5.8 GHz WLAN, 3.5/5.5 GHz WiMAX and 4 GHz C bands range. Good antenna gains and radiation behavior within the UWB frequency range have also been obtained. The antenna has a small dimension of 12× 18 mm2 . |
| Author(s): | N. Ojaroudi, M. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 637 KB |
| Title: | Calculation and Analysis of Shielding Effectiveness of the Rectangular Enclosure with Apertures |
| Abstract: | Based on transmission line theory, an approach which combines the analytical model developed by Robinson et al. and the model which analyses the shielding effectiveness (SE) of enclosure with an off-centre aperture or aperture array is presented. The model is more general than other methods and includes the incident wave with varied polarization angles and incident angles. It is quicker to calculate the SE with this model, which on the other hand enables to investigate the effect of important design parameters on SE. This model is validated by comparing the SE predictions with those from literatures. Different aspects’ effect on the SE are investigated such as aperture dimension, enclosure dimension, position of observation point, number of apertures, polarization angles, and incident angles, etc. |
| Author(s): | C. C. Wang, C. Q. Zhu, X. Zhou, Z. F. Gu |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 494 KB |
| Title: | Multi-Resonance Monopole Antenna with Variable Band-Notch Performance for UWB Applications |
| Abstract: | In this paper, a novel multi-resonance monopole antenna with frequency band-notched function is presented. By cutting a pair of rotated ? -shaped slots in the ground, the bandwidth is improved, that achieves a fractional bandwidth with multi resonance performance of more than 160 %. In order to achieve single band-rejected function an S-shaped parasitic structure was inserted in the ground plane and a frequency notched band of 5.03 GHz – 5.98 GHz has been received. The measured results reveal that bandwidth of proposed antenna is from 2.75 GHz to 18.73 GHz for VSWR < 2. Simulated and experimental results obtained for this antenna show that it exhibits good radiation behavior within the UWB frequency range. The designed antenna has a small size of 12?18 mm2. |
| Author(s): | N. Ojaroudi, M. Ojaroudi, N. Ghadimi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 546 KB |
| Title: | High-Resolution and Jamming-Resistant Adaptive Synthetic Aperture Radar Imaging System based on UWB-OFDM Waveform |
| Abstract: | A novel approach for jamming-resistant and high-resolution synthetic aperture radar (SAR) imaging technique is explored based on ultrawideband orthogonal frequency division multiplexing (UWB-OFDM) waveform. Suitable waveforms for both friendly and hostile environment are proposed based on various random sequences and tested for SAR imaging in presence of a digital radio frequency memory (DRFM) repeat jammer. Adaptivity factor is introduced to make the system consistent in both environments. Wide-band ambiguity function (WAF) has been derived and the effect of subcarrier composition in UWB-OFDM waveform as SAR signal is analyzed to avoid ambiguity in image reconstruction. Appropriate UWB-OFDM pulse shaping is introduced for SAR imaging in jamming scenarios and in hostile environments to solve the susceptibility of conventional linear frequency modulated (LFM) chirp signal, Gaussian pulses and any other constant pulse shape to avoid the possibility of false target introduced by jammer and to achieve secured imaging in jamming scenarios. The peak side-lobe performance is examined in terms of number of OFDM sub-carriers and sub-carrier orientation. |
| Author(s): | M. A. Hossain, I. Elshafiey, M. A. S. Alkanhal |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 6 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1330 KB |