ACES Publication Search
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| Title: | ACES Journal July 2013 Full Issue |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 7836 KB |
| Title: | ACES Journal July 2013 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 394 KB |
| Title: | Frequency-Domain Solution to Electromagnetic Scattering from Dispersive Chiroferrite Materials |
| Abstract: | Main purpose of this paper is to present a solution to electromagnetic scattering by bianisotropic dispersive materials. The presented solutions provide a reference baseline that can be used for comparison reasons by other researchers dealing with scattering by bianisotropic dispersive media. The solution algorithm based on the method of moments and mixed potential equations is tested through a few cases of dispersive scatterers and first known solutions to these problems are obtained. The proposed method has an advantage over the time domain methods as it does not rely on the Z-transform of the analytical expressions necessary to be used when dispersive media are present in the problem of interest. |
| Author(s): | M. Hasanovic, C. Mei, J. K. Lee, E. Arvas |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 857 KB |
| Title: | Dissipative Scheme for Discontinuous Galerkin Time-Domain Method Based on a Leap-Frog Time-Stepping |
| Abstract: | A dissipative scheme is proposed to improve numerical dispersion and eliminate spurious modes in the unstructured grid-based discontinuous Galerkin time-domain (DGTD) method. We introduce the dissipative terms into the centered fluxes, and a backward discretization in time is applied to the dissipative part to yield a fully explicit time-stepping scheme. In order to analyze the dispersion and dissipation properties of this scheme, we perform a numerical Fourier analysis to the normalized one-dimensional Maxwell’s equations with periodic boundary conditions. In this process, the mechanism of suppression of the spurious modes is revealed for the dissipative scheme. Numerical results show that more accurate solutions can be obtained by using dissipative scheme in the DG method. |
| Author(s): | D. Peng, X. Tang, H. Yang, J. He |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 861 KB |
| Title: | Simulation, Fabrication, and Performance Comparison of a GPS Antenna with Radome on the Roof of an Automobile |
| Abstract: | In this work, a circularly polarized patch antenna, designed to operate at 1.57 GHz, is used for reception of GPS signals. Its analysis is carried out at first, by means of simulation, considering the following cases: antenna without radome and antenna with acrylic radome. It is shown that the radome produces a distortion of the electric field components. The antenna performance, with radome, was analyzed on several locations on the automobile, considering the effect of the complete chassis. Two cases of basic, a simplified and a more simplified advanced car models (BCM, SACM, and MSACM) were used in order to analyze the influence of chassis shape. Simulations demonstrate that the best location of the antenna is on the roof. Fabrication, experimental and practical tests are also presented. The performance analysis of the developed antenna, using it as a replacement one, is realized using a Garmin GPS and a GPS kit. |
| Author(s): | M. Tecpoyotl-Torres, J. G. Vera-Dimas |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 2679 KB |
| Title: | Tunable Bandstop Filter Based on Split Ring Resonators Loaded Coplanar Waveguide |
| Abstract: | In this paper, a novel electrical tunable bandstop filter based on coplanar waveguide (CPW) loaded with split ring resonators (SRRs) is proposed. The unit cell of the bandstop filter is formed by etching single SRR on the CPW back substrate side, and the SRRs can be excited by the CPW slot’s magnetic field. Lumped equivalent circuit models are developed to analyze the frequency responses, and it shows that by loading the common cathode varactor diodes at the split region of the SRR outer ring, the resonant frequency of the bandstop filter can be electronically adjusted by tuning the reverse voltage of the varactor diodes. The prototype with overall size of 26.6 mm ? 50 mm ? 0.508 mm was designed and fabricated to validate the proposed structure. The measured tunable resonant frequency of the fabricated bandstop filter is from 2.19 GHz to 2.31 GHz while a reverse bias voltage is varying from 0 V to 30 V. It also shows that the -10 dB bandwidth is less than 45 MHz. |
| Author(s): | Q. Xiang, Q. Feng, X. Huang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1138 KB |
| Title: | A Compact Planar 90° Branch Line Coupler Using S-Shaped Structure Loading for Wideband Application |
| Abstract: | This paper presents the design of a wideband microstrip branched branch line coupler (BLC). The wideband performance of the BLC means that it possesses equal coupling and difference of phases throughout the operating frequency band, from 4 GHz to 6 GHz (based on a 10 dB, i.e., VSWR ? 2). The compactness of the proposed design is depending on the replacement of the branched transmission lines (TL) instead of the ordinary TLs. Small and easy to fabricate microstrip layout topology for the BLC has been designed and constructed relying on a low cost dielectric material, the well-known FR4. In addition, the proposed coupler can be easily fabricated on the printed circuit board without any lumped element. The proposed BLC exhibits couplings and phase errors within ?3.75 ± 1 dB and 4° over a 60 % bandwidth (BW) with a center frequency of 5 GHz (based on 15 dB). |
| Author(s): | M. Maleki, J. Nourinia, Y. Zehforoosh, V. Rafii |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 660 KB |
| Title: | A Compact Stacked-Patch Endfire Antenna for WiFi Application |
| Abstract: | The new stacked-patch endfire antenna is proposed for wireless fidelity (WiFi) access point and base station. The proposed using three copper patches is presented. The new antenna uses easily fabrication. The advantage of the endfire antenna with three patches compared to the conventional Yagi antenna is a reduction in the length of the antenna and the dimension of the antenna is 0.504 ? × 0.664 ? × 0.075 ? mm3. The antenna has a gain of 9 dB, return loss better than - 10 dB around the WiFi band from 2.4 GHz to 2.483 GHz and the front-to-back can achieve 15 dB. We described the antenna structure and presented the comparison of simulation results with experimental data. The proposed antenna is fabricated, and measured reflection coefficient, radiation patterns, and gain are presented. |
| Author(s): | Y. Sun, G. Wen, P. Wang, Y. Huang, Z. Du |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 844 KB |
| Title: | Compact Planar Super-Wideband Antenna with Band-Notched Function |
| Abstract: | In this paper, the design of a novel printed monopole antenna is presented that operates across a super wideband frequency range (2.39 GHz to 40 GHz) and exhibits bandnotch characteristic that is necessary to eradicate interference from WLAN systems operating between 5.15 GHz ? 5.825 GHz. The prototype antenna consists of a radiating patch in the shape of an octagonal ring structure and embedded within ring is a rectangular strip. The antenna is excited through a microstrip feed-line and includes an elliptically shaped ground-plane that is defected with a dielectric notch in the vicinity of the patch. The proposed antenna’s structure is simple to design and is relatively inexpensive to fabricate. In addition, it is compact in size with overall dimensions of 30 × 30 × 1.6 mm3. The measured results confirm the impedance bandwidth cover a super wideband frequency range from 2.3 GHz ? 40 GHz, for VSWR ? 2 that corresponds to a fractional bandwidth of 178 %. The radiation characteristic of the proposed antenna is approximately omni-directional. |
| Author(s): | H. Shahsavari, J. Nourinia , H. Shirzad , M. Shokri , S. Asiaban , Zh. Amiri , B. Virdee |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1182 KB |
| Title: | Ultra-Wideband Modified CSRR Antenna with Reconfigurable Notch Band |
| Abstract: | A novel technique of realizing notches for a compact ultra-wideband (UWB) antenna is proposed based on a modified complementary split ring resonator (CSRR). The UWB slot antenna is in the swallow shape of a modified CSRR. The notched band centered at 5.8 GHz for upper WLAN and 3.9 GHz for C-band satellite communication systems. The proposed antenna has a compact size of 25 × 27.9 mm2. The measured results show that the proposed antenna can guarantee a wide bandwidth from 2 GHz to 12 GHz (VSWR < 2) with dual unwanted bandnotches successfully. The antenna demonstrates omnidirectional and stable radiation patterns across all the relevant bands. Moreover, a prototype of the dual-band-notched UWB antenna is fabricated and measured results are compared with simulated results. |
| Author(s): | D. Jiang, B. Yan, R. Xu |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1496 KB |
| Title: | Bandwidth Enhancement of Small Square Monopole Antennas by Using Defected Structures Based on Time Domain Reflectometry Analysis for UWB Applications |
| Abstract: | In this paper a simple printed monopole antenna with enhanced bandwidth by using defected structures for UWB applications is presented, which is designed due to time domain designing method. The proposed antenna consists of a square radiating patch with a defected mircostrip feed-line by a pair of T-shaped slits and a defected ground plane by a pair of rectangular slots with a T-shaped strip protruded inside the slots, which provides a wide usable fractional bandwidth of more than 130 % (3.06 GHz - 14.27 GHz). By cutting two modified Tshaped slits with variable dimensions on the feedline and also by inserting a pair of rectangular slots with T-shaped protruded strip inside the slots on the ground plane, additional resonances are excited and hence much wider impedance bandwidth can be produced. This large operating bandwidth is obtained by choosing suitable dimension for the proposed defected structures. To verify the validation of the proposed antenna, the equivalent circuit based on time domain reflectometry analysis is presented. Detailed simulation and numerical investigations are conducted to understand their behaviors and optimize for broadband operation. The designed antenna has a small size of 12 × 18 mm2, about 0.15? ? 0.25? at 4.2 GHz. The proposed antenna exhibits almost omnidirectional radiation patterns with low cross polarization level. |
| Author(s): | M. Ojaroudi, E. Mehrshahi |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 926 KB |
| Title: | Novel Varactor-Tuned Balanced Bandpass Filter with Continuously High Common-Mode Suppression |
| Abstract: | In this letter, a novel balanced varactor-tuned bandpass filter (BPF) designed by using the half-wavelength microstrip resonators is proposed. The frequency-tuning mechanism of the resonator is analytically investigated for designing the proposed balanced BPF. By adding a tunable capacitor to the center of the resonator, it is noted that the common mode can be suppressed to a great extent in the frequency-tuning range of the differential-mode passband. Also, it has no effect on the differential-mode response. For demonstration, a balanced BPF is designed and fabricated. The simulated and measured results with good agreement show that the center frequency of the differential-mode passband can be tuned from 0.725 GHz to 0.811 GHz, while the common-mode suppression in this frequency range is always more than 25 dB. |
| Author(s): | Q. Y. Lu, J. X. Chen, L. H. Zhou, H. Tang |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 650 KB |
| Title: | A Novel Design of Reconfigurable Monopole Antenna for UWB Applications |
| Abstract: | In this paper, a kind of reconfigurable monopole antenna with multi-resonance and switchable band-notched function is designed and manufactured whose frequency characteristics can be reconfigured electronically to have a singleband notch function in order to block interfering signals from 5.15 GHz - 5.35 GHz HiperLAN, 5 GHz - 6 GHz WLAN or 7.25 GHz - 7.75 GHz for downlink of X-band satellite communication systems. The proposed antenna consists of a square radiating patch, feed-line, and a ground plane with a Fork-shaped conductor-backed plane. By adding an inverted T-shaped and a pair of Lshaped parasitic structures in the ground plane, additional resonances are excited and hence much wider impedance bandwidth can be produced, especially at the higher band, which provides a wide usable fractional bandwidth of more than 135% (3.05 GHz-16.51 GHz). In order to generate reconfigurable band-stop performance, we use a pair of PIN diodes within the antenna configuration. By changing the ON/OFF conditions of the PIN diodes, the antenna can be used to generate a single notch band to isolate and block any interference in the UWB frequency range. The proposed antenna has a small dimension of 12 × 18 × 1.6 mm3. |
| Author(s): | N. Ojaroudi , S. Amiri, F. Geran |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 1006 KB |
| Title: | Miniaturized Microstrip Lowpass Filter with Ultra-Wide Stopband |
| Abstract: | A new microstrip lowpass filter with compact size and ultra-wide stopband is presented. Using triangular patch resonators and butterfly resonator with four 45° radial “wing” patches, the introduced filter can successfully realize compact design and ultra-wide stopband. To further reduce the circuit size of the filter, the meander transmission lines are also adopted in the design. A demonstration filter with 3 dB cutoff frequency at 1.6 GHz has been designed, fabricated, and measured. Measured results show that the lowpass filter has an ultra-wide stopband bandwidth of 153.9 %, which is able to suppress the 11th harmonic response. Furthermore, it also has a small size of 14 ? 15 mm2, which corresponds to 0.114 ?g ? 0.122 ?g, where ?g is the guided wavelength at 1.6 GHz. |
| Author(s): | Y. Dou, J. Wang, H. Cui, J. L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 28 Number: 7 Year: 2013 |
| Download Link: | Click here to download PDF File Size: 805 KB |