ACES Publication Search
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| Title: | ACES Journal November 2018 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2163 KB |
| Title: | ACES Journal November 2018 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 836 KB |
| Title: | ACES Journal November 2018 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 19766 KB |
| Title: | Mutual Coupling Compensation in Transmitting Arrays of Thin Wire Antennas |
| Abstract: | This paper presents a numerical technique for the compensation of mutual coupling in transmitting arrays of thin wire antennas. The Method of Moments is used to compute the scattering parameters of the array. Using these parameters and the original excitations, a set of new excitation values are computed. The new excitation values compensate the effect of the mutual coupling. Computed results are given for linear, circular, and 3-Dimensional arrays. Uniform and binomial excitations are studied. Results obtained are compared with other available data and very good agreement is observed. |
| Author(s): | S. Khan, H. Sajjad, M. K. Ozdemir, E. Arvas |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2455 KB |
| Title: | Series-fed Dipole Array for Near-field RFID Application |
| Abstract: | In this paper, the series-fed dipole array is proposed and studied for near-field radio frequency identification (RFID) applications. The dipole array is composed of several dipoles with a series feed line. Closed form expressions for current distribution and near-field distribution are presented in this paper. To verify the feasibility of this kind of antenna as a reader antenna in near-field ultra-high frequency (UHF) RFID, a prototype that contains three dipoles is designed, fabricated and tested. The theoretic analysis, simulations and experiments agree well and it is shown that the series-fed dipole array is capable of generating strong magnetic field over a rectangular area, which is very useful in near-field UHF RFID applications. |
| Author(s): | Y. Wang, L. Shen, C. Huang, J. Zhu, W. Tang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2050 KB |
| Title: | Compact Antenna Array with Newly Designed Decoupling Network |
| Abstract: | The design of a compact two-element antenna array with highly isolated ports is presented in this paper. The high port isolation is achieved by inserting a decoupling network between the ports of the antenna elements. The decoupling network is designed based on the method of eigen-mode analysis and is realized by the simple microstrip lines. The systematic design procedure of the decoupling network is presented. The achieved microstrip decoupling network is simple and easy to fabricate. The measured results show that the isolation between the antenna ports has been increased by more than 13 dB for a two-element monopole array with the element spacing of 0.1lambda. |
| Author(s): | T. Dong, Y. Yu, M. Li, H. Zeng |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1696 KB |
| Title: | Dual-Polarized Antenna Based on Metal Ring and Microstrip Patch |
| Abstract: | Based on the principle of the complementary antenna, a kind of dual-polarized antenna element is studied, which combines the metal ring and rectangular microstrip patch. The antenna separates the rectangular microstrip patch and the metal ring on a vertical space, and the metal ring is equivalent to a current radiation source. The rectangular microstrip patch is equivalent to a magnetic flux radiation source, which respectively radiates and receives two orthogonal polarized electromagnetic wave components to achieve dual polarization. A metal reflector ground is introduced to realize the uni-direction radiation pattern, and the front-to-back ratio of the pattern has been improved. The simulation results show that the isolation between two polarization ports is 22dB within the frequency range of 4.94GHz~5.06GHz. The measured results of the fabricated antenna indicate that the Voltage Standing Wave Ratio (VSWR), port isolation degree and the cross polarization level can satisfy technical requirements. And design effectiveness of the dual-polarized antenna in this paper was proved. The dual-polarized antenna studied in this paper has been suitable for some application fields such as phased array radar and the research results lay the technical foundation for the practical engineering application. |
| Author(s): | L. Song, S. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2017 KB |
| Title: | Reconfigurable Array Designed for Directional EM Propagation using Energy Band Theory of Photonic Crystals |
| Abstract: | A type of reconfigurable array consisting of metal rods was designed for directional electromagnetic (EM) wave propagation at microwave frequency. By adding or removing a part of metal rods, the designed array can be reconfigured between a hexagonal-lattice array and a rectangular-lattice array. As a result, the directional radiation pattern can be changed. In this study, the method of designing metal photonic crystals array is proposed. Dispersion curves of Energy band theory of photonic crystals were computed and integrated with the theory of finite thickness periodic arrays. Measurement results are well consistent with the simulation results, suggesting that the antenna as a radiation source located in the center of the hexagonal-lattice array could reach good directionality at the designed frequency. When the array is transformed into the rectangular-lattice array by adding or removing a part of metal rods, the directional radiation pattern can be changed ±30 degrees at the same frequency. |
| Author(s): | Y. Zhang, Z. Cao, G. Lu, D. Zeng, M. Li, R. Wang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2434 KB |
| Title: | Coverage Prediction for Triple Diffraction Scenarios |
| Abstract: | Electromagnetic waves emanating from the transmitter can reach to the receiver by reflection, direct or diffraction mechanism. In urban areas, dominant mechanism is diffraction. Thanks to using of high frequency, the obstructions can be modeled as a knife-edge. Coverage prediction is vital to install reliable and high-quality communication systems. In this study, a triple diffraction coefficient is derived for Uniform Theory of Diffraction (UTD) model and used for coverage problem. Coverage problems could be solved by the developed program in MATLAB computationally. Simulation results obtained in developed program are compared with FEKO electromagnetic wave propagation simulation software. |
| Author(s): | M. B. Tabakcioglu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1957 KB |
| Title: | Circular Concentric-Ring Reflectarray Design Using a Coaxial Wedge Unit Cell |
| Abstract: | This paper presents a design methodology for a concentric ring reflectarray using angular periodic structures. This paper also examines the coaxial wedge unit cell using the waveguide simulator method and contrasts it to the coaxial unit ring approach. The coaxial wedge unit cell approach is seen to offer a more efficient and more extendable means of simulation than the coaxial unit ring approach. |
| Author(s): | J. S. Roper, A. F. Peterson |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2101 KB |
| Title: | Single Layer Reflectarray Antenna with Pie-Shaped Elements for X-band Applications |
| Abstract: | In this paper, a single-layer reflectarray design is presented for X-band applications. The reflectarray comprises of pie-shaped reflective elements. The unit element has compact dimensions of 0.28lambdao × 0.28lambdao. The major segment angle of pie-shaped element controls the reflection phase range and offers a total of 650º phase variation. A reflectarray prototype comprising 23 × 23 elements is realized to demonstrate the necessary reflection characteristics. Different parameters are analyzed for performance evaluation of the reflectarray. The proposed reflectarray offers measured gain of 24 dBi with 1-dB and 3-dB gain bandwidth of 18% and 28% respectively. Moreover, side-lobe-levels and cross-polarizations are less than 22 dB and 35 dB respectively. |
| Author(s): | T. Shabbir, R. Saleem, S. U. Rehman, M. F. Shafique |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2011 KB |
| Title: | Efficient Computation of SAR and Temperature Rise Distributions in a Human Head at Wide Range of Frequencies Due to 5G RF Field Exposure |
| Abstract: | In this paper, the effects of radio frequency electromagnetic fields produced by base stations on a human head are investigated with the aid of a multiphysics model at multiple frequencies using a single simulation. This multiphysics model is based on integrating the Debye model of human head dispersive tissues parameters into the finite-difference time-domain method by using the auxiliary differential equation approach and then calculating the specific absorption rate and temperature rise distributions in the head with the use of bioheat equation. The effects of frequency and incident angle of radio frequency electromagnetic fields on the specific absorption rate and temperature rise distributions in the head are analyzed. |
| Author(s): | F. Kaburcuk, A. Z. Elsherbeni |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1967 KB |
| Title: | A Novel Adaptive Tracking Algorithm for the Resonant Frequency of EMATs in High Temperature |
| Abstract: | Resonant frequency drift of electro-magnetic acoustic transducers (EMATs) is a common phenomenon in high temperature, resulting in a low conversion efficiency. In this work, for tracking the resonant frequency of EMATs automatically, a novel adaptive radial basis function neural network (RBFNN) with guaranteed transient is proposed. First, the configuration and dynamic behavior of EMATs are introduced at room temperature. Then, the initial system under the constraint of transient performance index is converted into a new unconstrained equivalent system by the error conversion mechanism. Furthermore, the adaptive tracking control for the resonant frequency is analyzed in detail. Finally, the validity and effectiveness of the proposed novel method are verified by numerical simulations. |
| Author(s): | X. Jia, Q. Ouyang, T. Zhang, X. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2186 KB |
| Title: | Microwave Imaging Based on Time Reversal Mirror for Multiple Targets Detection |
| Abstract: | Time reversal (TR) is an applicable technique for target detecting and has gained extensive attention due to its self-adaptive focusing ability. However, the imaging performance of the traditional time reversal mirror (TRM) deteriorates in multiple targets cases. A TR imaging approach for multiple targets detection is proposed in this paper. Different from the direct retransmission of the TR signals, the time domain gating is applied to the targets responses to divide them into different groups, and the optimal time frame corresponding to each target which will be utilized in the subsequent step is calculated. After the retransmission of the gated TR signals, the essential zero setting step and the summation step are conducted to construct the imaging function. Numerical simulations are carried out for three multi-targets cases using the finite-different time-domain (FDTD) method. The imaging results are compared with the traditional TRM method and indicate the effectiveness and the superiority of the proposed approach. |
| Author(s): | T. Mu, Y. Song |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2001 KB |
| Title: | Optimal Design of Microwave Devices by Fitness-estimation-based Particle Swarm Optimization Algorithm |
| Abstract: | As important parts of modern communication systems, microwave devices play a decisive role in communication quality. When optimizing the complex microwave devices, the global optimization algorithm is generally used exploiting full-wave electromagnetic simulation software. The full-wave electromagnetic simulation software evaluates the performance of the microwave device. Based on this evaluation result, the global optimization algorithm is used to design the microwave device. This ordinary method can achieve high accuracy, but the main disadvantage is time-consuming. It takes a long time and sometimes takes days or even weeks. In order to improve the efficiency of the optimization of microwave devices, this research presents a method called fitness-estimation-based particle swarm optimization (fePSO). According to the explicit evolution formula of particle swarm optimization (PSO), the particles fitness predictive model is constructed. From the third generation, the fitness value is estimated by the predictive model, so as to replace the time-consuming full-wave electromagnetic simulation when optimizing complex microwave devices. Thereby it can greatly reduce the evaluation time of the fitness, shorten the entire optimization process, and improve the design efficiency. This method is validated by optimizing Yagi microstrip antenna (MSA) and hairpin SIR band-pass filter. The results show that the efficiency can be increased by about 90% with the assurance of design accuracy, so the purpose of rapid optimization has been achieved. |
| Author(s): | X.-H. Fan, Y.-B. Tian, Y. Zhao |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1946 KB |
| Title: | An Irregular Ground Oriented Miniaturized Antenna for UWB Industrial Applications |
| Abstract: | In this paper, a new small UWB antenna for different UWB industrial applications is presented. The proposed prototype comprises of a simple structure with a modified triangular patch and a sawtooth ground plane. The electrical size of the proposed antenna is 0.15lambda× 0.13lambda×0.014lambda, at lower end frequency. The patch and ground plane is optimized and analyzed. The antenna shows 116% of VSWR<2 impedance bandwidth from 2.8 to 10.5 GHz with a peak gain of 5.6 dBi and 75% of the average radiation efficiency. The proposed design established a nearly omnidirectional radiation characteristic over the operating frequency band. The proposed antenna was successfully simulated, prototyped, and measured. The uniqueness of the proposed antenna is the miniaturization of the antenna for the UWB frequency band, which can be applied for different portable and convenient UWB applications. |
| Author(s): | M. Z. Mahmud, T. Alam, M. Samsuzzaman, A. Ullah, M. T. Islam |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2522 KB |
| Title: | A CPW Fed T-shaped Frequency Reconfigurable Antenna for Multi Radio Applications |
| Abstract: | This paper deals with design, simulation and experimental analysis of a compact, Coplanar Waveguide (CPW) fed T-shaped reconfigurable antenna with frequency diversity. The antenna mainly comprises of four strips placed in T-shape fed by coplanar waveguide feed which operates at 5.8GHz. The reconfigurability in frequency is achieved by connecting four strips through three switches in main antenna structure by the use of Positive-Intrinsic-Negative (PIN) diodes. By operating the switches in a controlled manner, the antenna is able to operate at seven frequencies namely 5.82GHz, 5.46GHz, 5.26GHz, 5.15GHz, 4.69GHz, 3.93GHz, and 3.21GHz which are suitable for Wi-Fi, WiMAX, WLAN, other C-band, and S-band applications. The antenna aperture area is 35mm × 30mm and it is designed on a FR4 epoxy substrate whose dielectric constant epsilon r=4.3, thickness h=0.8mm. A parametric study has been carried to analyze the characteristics of the proposed antenna. The measured results are in good agreement with simulation results and show that the antenna exhibits good radiation behavior in the specified application bands. |
| Author(s): | S. Chilukuri, K. Dahal, A. Lokam, W. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2773 KB |
| Title: | A Resonance Prediction Method for a Shielding Enclosure with Apertures Illuminated by a Plane Wave |
| Abstract: | Electromagnetic resonances in a shielding enclosure with apertures could result in significant degradation of its shielding performance. In this paper, an analytical method is proposed to predict the resonances of a shielding enclosure with aperture arrays illuminated by a plane wave. Firstly, an obliquely incident and arbitrarily polarized plane wave is decomposed into several normally incident plane waves each polarized in the axis direction. Then, the transmitted fields through each aperture are equivalent to fields radiated by a magnetic current located at the center of the corresponding aperture. Finally, the resonant modes and resonant frequencies of the enclosure are determined according to the direction of the magnetic current and the properties of the radiated fields. This method is verified by comparing its results with the results of full-wave simulations. Compared with numerical methods, the method is easier to implement and more efficient in predicting resonances. |
| Author(s): | B.-L. Nie, Z. Cao, P.-A. Du |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1704 KB |
| Title: | Fast Analysis of Electromagnetic Scattering from a Coated Conductor with the Parabolic Equation |
| Abstract: | In recent years, the electromagnetic scattering from the coated conductors has been paid more and more attention by many scholars. The parabolic equation (PE) method is firstly utilized to analyze electrically large conductors coated with lossy medium in this paper. The impedance boundary condition is implemented to analyze the lossy medium and the implicit finite difference method of Crank–Nicolson scheme is implemented to solve the parabolic equation. As a result, the computations can be taken in each two-dimensional transverse plane. By this means, both the CPU time and memory requirement are reduced greatly. Numerical results are given to demonstrate the accuracy and efficiency of the proposed method. |
| Author(s): | Z. He, H.-C. Yin, R.-S. Chen |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1854 KB |
| Title: | Protection of Computer Enclosure against Coupled Electromagnetic Interference |
| Abstract: | In this paper some suggested protection methods is proposed to improve the shielding effectiveness of computer enclosures. Slots and holes on the computer enclosure are divided into five types, and the coupled electromagnetic interference (EMI) into the enclosure is computed using the finite-difference time-domain (FDTD) method when each type slot exists. From comparison of both time domain electric field waveform and field distribution in the enclosure, vent array, joint laps, CD-ROM and display are found to be the main ways that the EMI penetrated into the enclosure. To improve the protection of the enclosure, waveguide window is used to replace vent array. Additionally, rivet number is increased, depth of the joint laps is increased and conductive gaskets are filled into the joint laps. From numerical analyses, it can be demonstrated that the suggested methods are efficient to improve shielding effectiveness of the computer enclosure. Some suggested methods are also proposed for the CD-ROM and display protection. |
| Author(s): | R. Xiong, W. Yang, H.-L. Chen, Y.-T. Duan |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2782 KB |
| Title: | Effect of Aspect Ratio and Frequency of an Open-Ended, Coaxial Line on Admittance for Determination of Moisture in Tenera Oil Palm Fruit Using Finite Difference Method |
| Abstract: | This paper intends to study the effect of variations of aspect ratio (the ratio of outer radius to inner radius of conductor) and frequency to the normalized admittance (normalized conductance and susceptance) of oil palm fruit with various moisture content (MC) on performance of RG405/U semi-rigid cable (open-ended coaxial line). Both finite difference method (FDM) and quasi-static model (admittance model) were used to compare response of normalised conductance and susceptance due to 30%, 40%, 60%, 70% and 80% of moisture content that explain all ripeness stage of oil palm fruit. Finite difference method is used to simulate complex admittance due to different MC in oil palm fruit in various ripeness. The FDM results were then compared with the quasi-static model through error analysis. The aspect ratio of 3.298 has smaller error of normalized conductance when frequency range <3 GHz. |
| Author(s): | E. M. Cheng, Z. Abbas, M. Abdulmalek, K. Y. You, K. Y. Lee, N. F. Mohd Nasir, M. S. Abdul Majid, S. F. Khor |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 1948 KB |
| Title: | Modeling and Experiment on Active Magnetic Bearing as Force Actuators to Detect Inner Race Fault of Rolling Element Bearing |
| Abstract: | As one of the important components in the rotating machinery, the condition of rolling element bearing has a great impact on the system performance. Therefore, the fault detection for the rolling element bearing is important and many methods have been proposed. Following our previous work on the outer race defect diagnosis, in this paper, the active magnetic bearing (AMB) is employed as an exciter to apply electromagnetic force to detect the inner race defects. The theoretical model of a nonlinear bearing-pedestal system model with the inner race defect under the electromagnetic force is developed and investigated. The simulation and experimental results show that the characteristic signal of inner race defect is amplified under the electromagnetic force through the AMBs, which is helpful for improving the diagnosis accuracy. |
| Author(s): | Y. Xu, J. Zhou, C. Jin |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2583 KB |
| Title: | Calculating Electromagnetic Force Created by Static Suspension Device Used in Permanent Magnet Electrodynamic Suspension Vehicle |
| Abstract: | In response to the shortcomings of existing devices, a novel electrodynamic suspension (EDS) device—based on a semicircular track and cylindrical permanent magnet (PM) Halbach array—is presented in this paper. It enables a vehicle to statically levitate above a semicircular track. In order to calculate the electromagnetic force created by this novel device, we first create a 2-D equivalent linear model of the cylindrical PM Halbach array, build differential equations (based on the linear model) for the magnetic vector potentials, and produce the expression of the electromagnetic force per unit length by solving the equation system. Next, by integrating the electro-magnetic force per unit length with the arc direction of the inner semicircular track, the vertical electro-magnetic force created by the novel device can be determined. Analytic expression results, and those of a finite element analysis (FEA) model built by Maxwell are compared, and show the average relative error to be 3.02%. The novel device is rational, and the analytic expression is accurate. |
| Author(s): | W. Zhang, K. Zhang, Y. Chen, X. Liu |
| File Type: | Journal Paper |
| Issue: | Volume: 33 Number: 11 Year: 2018 |
| Download Link: | Click here to download PDF File Size: 2025 KB |