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Title: ACES Journal September 2016 Cover
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: ACES Journal September 2016 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: ACES Journal September 2016 Full
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: A New Power Series Solution Approach to Solving Electrically Large Complex Electromagnetic Scattering Problems
Abstract: In this work, we present a new power series solution procedure to obtain induced currents and scattered elds on a large conducting body due to a plane wave incidence. The procedure follows standard method of moments approach yet is applicable to electrically large problems. The rst step involves approximating the given structure via standard geometrical discretization and de ning the conventional basis functions to approximate the induced current. The next step involves gathering the total number of basis functions into a small number of groups thereby casting the moment matrix into a collection of submatrices representing self and mutual interaction between the groups. Next, the procedure involves eliminating the interaction of two immediate neighbors on any selected group. This process results in a diagonally-dominant moment matrix assuming the group size is suciently large. Also the procedure sets the matrix blocks residing on either side of the diagonal block to zero. The new matrix equation can be solved in many ways eciently. However, this work proposes using power series approach to obtain accurate solution results. The present approach is simple, e- cient, highly amenable for parallel processing, and retains all the advantages of conventional method of moments scheme. Several numerical examples are presented to validate the numerical method.
Author(s): S. M. Rao, M. S. Kluskens
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Formulations for Modeling Voltage Sources with RLC Impedances in the FDTD Method
Abstract: Voltage sources are modeled with constant resistive internal impedances when simulated in the finite-difference time-domain (FDTD) method in most of the applications. However, some applications, such as an RFID tag antenna in radiation mode, require modeling of voltage sources with frequency dependent complex impedances. If the frequency dependent behavior of the complex impedance of a voltage source follows that of an RLC circuit, the voltage source can be modeled with an RLC internal impedance in the FDTD method for wide-band simulations. This paper presents FDTD formulations to model a voltage source with an RLC impedance for the cases where the RLC circuit is a series or a parallel connected RL, RC, or an RLC configuration.
Author(s): V. Demir
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Simulation Validation of Experimental Tests for Automotive System EMC Developmental Tests
Abstract: The development and testing of automotive (sub)systems, particularly for Electromagnetic Compatibility (EMC), usually requires expensive test facilities. This paper describes the use of electromagnetic simulation to demonstrate the level of confidence that can be placed in measurements taken in more general laboratories, thus giving an estimate of the accuracy these facilities can provide. This is important in order to enable/allow more developments in automotive systems from research and development teams without standards compliant test facilities. This is, itself, important because of current developments in all-electric and autonomous vehicles. This paper demonstrates, through the use of full wave simulation representing a theoretically ideal environment compared with two different practical approaches, that EMC analysis can be undertaken with a reasonable estimation of accuracy and provides a framework for pre-compliance or developmental testing.
Author(s): G. Braglia, A. Duffy, S. Barmada
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: A Novel Asterisk-Shaped Circularly Polarized RFID Tag for On-Metal Applications
Abstract: An asterisk-shaped, metal-mountable RFID tag with a minuscule footprint is presented. The proposed design makes use of multiple asymmetric slots patterned in a cross-shaped fashion to achieve circular polarization. The structure is excited capacitively using a terminally-grounded, T-shaped feed line positioned within the slots. This peculiar arrangement permits the attainment of circular polarized radiation characteristics over a wide band of operation. Impedance matching, antenna size reduction and read range enhancement are the additional advantages offered by the embedded feed line. The final design is realized on a commercially available FR-4 substrate over dimensions of 40 x 40 mm2 yielding an impedance bandwidth and an axial ratio bandwidth of 37 MHz and 20 MHz, respectively. Improvement in antenna gain (and consequently in the read range) is reported upon mounting the tag on metallic surfaces.
Author(s): U. H. Khan, B. Aslam, J. Khan, M. Nadeem, H. Shahid, M. A. Azam, Y. Amin, H. Tenhunen
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Area Spectral Efficiency of a Macro-Femto Heterogeneous Network for Cell-Edge Users under Shadowing and Fading Effects
Abstract: The traditional macro-only network is not effective, especially when communication signal is required for users far away from the macrocell base station and located in the cell edge. The signal strength reaching these users is excessively attenuated due to fading and shadowing. The deployment of femtocells around the cell edge of this macrocell helps to reduce the effect of fading and shadowing thereby increasing the overall efficiency of the cellular network. This holds a great promise for adaptive space-based wireless sensor networks, formation-flying satellites and constellations.
Author(s): M. C. Uko, U. S. Ukommi, S. C. Ekpo, R. Kharel
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: A Simple UWB Tapered Monopole Antenna with Dual Wideband-Notched Performance by Using Single SRR-Slot and Single SRR-Shaped Conductor-Backed Plane
Abstract: This paper presents the design of a compact UWB antenna with dual band-notch characteristics in the 5 GHz band and X-band satellite communications. The proposed antenna consists of a tapered antenna fed by a microstip feed-line presenting a modified ground plane to achieve a wide impedance bandwidth, in the interval 2.8-12 GHz, with VSWR<2. The electromagnetic coupling of the tapered patch with the rectangular split ring resonator shaped parasitic conductor placed in the ground plane yields the first frequency notch which ranges from 5.05 to 5.95 GHz, in order to eliminate the dedicated short-range communications and wireless local area network interferences. The rejection of the X-band from 7.25 to 8.4 GHz, is achieved by etching a single rectangular split ring resonator slot in the radiator patch. Prototypes of the proposed antenna design were measured and compared to simulations, and good agreement was obtained.
Author(s): A. Naghar, F. Falcone, A. Alejos, O. Aghzout, D. Alvarez
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Tunable Metasurfaces for Filtering the Electromagnetic Waves Under Different Excitations
Abstract: In this study a tunable metasurface has been presented and evaluated for different excitation types. Tunability has been achieved by changing the substrate and geometrical properties. In order to obtain uniqueness, a parameter retrieval for the effective permittivity and permeability is performed using a version of the Nicholson-Ross-Weir (NRW) algorithm that is improved by implementing the Kramers-Kronig relationship. The results regarding the parametric and retrieval analysis are presented.
Author(s): S. Can, E. Karakaya, F. Bagci, A. E. Yilmaz, B. Akaoglu
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Design of Compact Novel Dual-Band BPF Using Open-Loop Dumbbell Shaped Defected Ground Structure and Step Impedance Cross-Shaped Lines with Independently Controllable Frequencies and Bandwidths
Abstract: In this paper a compact novel dual-band bandpass filter (DB-BPF) with independently controllable frequencies and bandwidths is presented and the procedure of its design is discussed. The proposed filter consists of an open-loop dumbbell shaped (OLDS) defected ground structure (DGS) and step impedance cross-shaped lines (SICSLs). To generate the first band, the authors used a pair of end-coupled uniform transmission lines with equal-length on the top and an OLDS outline symmetrically was etched in the ground plane. In addition, by introducing cross-shaped lines, a dual band function is achieved. In the proposed structure, in order to reject the unwanted harmonic pass bands, step impedance transmission lines are implemented along the ports of the filter. The fabricated filter has the merits of simple topology, compact size, good return loss, low insertion loss and high isolation. The measurement agrees well with the simulation.
Author(s): R. Khosravi, Ch. Ghobadi, J. Nourinia, M. Abbasilayegh, B. Mohammadi
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Dual High-Selectivity Band-Notched Ultra-Wideband Filter with Improved Out-of-Band Rejection
Abstract: A novel microstrip ultra-wideband (UWB) filter with dual notched bands is presented. By placing a simple dual-mode resonator having two symmetrical outer high-impedance lines beside the UWB filter, two controllable rejection bands are created, each of which features two resonant modes and high frequency selectivity. Defected ground structure techniques (DGS) is applied to realize wide out-of-band attenuation. To explain band-notched operating mechanism, the parametric studies and equivalent circuit of the proposed structure are presented. The experimental results agree well with the predicted results declaring the advantages of the proposed structure with high-selectivity widebandwidth notched bands and improved out-of-band rejection.
Author(s): Y. J. Guo, X. H. Tang, K. D. Xu
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Design of a Compact Wideband Filtering Power Divider with Improved Isolation
Abstract: A novel design of wideband filtering power divider (FPD) with high selectivity, good isolation and widen upper stopband is presented in this paper. A new topology is proposed by adding an isolation resistor between two tri-mode resonators to guarantee the isolation. Besides, owing to the intrinsic characteristics of tri-mode resonators and coupled lines with one of them terminated by an open-circuited stub, four transmission zeros (TZs) can be generated outside the operating band to improve the signal selectivity. For demonstration, a FPD operating at 2.35 GHz with 3-dB fractional bandwidth of 25.6% is designed, fabricated and measured. The measured isolation is better than 15.5 dB and the upper stopband is extended to 7.6 GHz (3.23f0) with a rejection level of 20 dB.
Author(s): Y. Deng, Y. He, J. Wang
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
Download Link:Click here to download PDF     File Size: 1771 KB

Title: Integrated RFIC On-Chip and GPS Antenna with Human Body forWrist and Wearable Communication Applications
Abstract: A GPS and Miracast RFIC-on-chip antenna in 0.18 um CMOS 1p6M process is presented. The HFSS 3-D EM simulator is employed for design simulation. A printed 1.575 GHz and 2.4 GHz antenna has been realized by using the CMOS RFIC-on-chip. The measured VSWR is less than 2 from 1.575 GHz and 2.4- to 2.483-GHz. This propose super quadric combo antenna in free space, electromagnetic coupling between super quadric antenna and human body and rectangular antenna for wrist watch type wireless communication applications. The measured phase distribution of the input impedance is quite linear and the H-plane patterns are almost omnidirectional and field tried GPS integration. In addition, in order to improve the way controlling this provide switch by software, a novel circuit structure which will control antenna pattern switching automatically by hardware is also developed for wireless healthcare and mobile biomedical application. RFIC-on-chip GPS and Miracast antenna also merger T/R-Switch design on single chip solution for 2.4GHz CMOS transceiver RF front-end. The old man can monitor healthcare and transfer to health center or passive devices by Miracast with software and show GPS location for wearable ambulatory application.
Author(s): W. C. Lai, J. F. Huang
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Mutual Coupling Reduction of Dual-Frequency Patch Antenna Arrays
Abstract: In this paper, a compact patch antenna array with dual resonant frequencies is presented. The mutual coupling between array elements can be reduced simultaneously at two frequencies by inserting a simple C-shaped resonator between the radiating patches and etching an inverted C-shaped slot defected ground structure (DGS) on the ground plane. The characteristics of the DGS and the resonator are investigated, respectively. The measured results show that the isolation between the antenna ports has been enhanced about 10 dB and 18 dB at the two operation frequencies with the presence of the proposed DGS and resonator structure.
Author(s): Y. Yu, L. Yi, X. Liu, Z. Gu
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: DOA Estimation for Unequal Power Sources using Extremely Low Profile Aperture Coupled Microstrip Antenna
Abstract: In this paper, an aperture coupled microstrip antenna with extremely low profile (0.022?c, ?c is the wavelength of the center frequency) is proposed and then applied to direction of arrival (DOA) estimation for unequal power sources. Two serial coupling slots resonating at connected frequencies are employed to expand the bandwidth of this microstrip antenna with extremely low profile. Compared with the microstrip antenna fed by a single coupling slot, the bandwidth is increased to 1.37% by using two serial coupling slots. Measurements of the antenna prototype exhibit 6.63% bandwidth (S11 < ?10 dB) and agree well with the simulation results. The measured antenna gain is 5.79 dBi, and the 3 dB beam width is 56 and 112 in the E-plane and H-plane, respectively. In addition, the crosspolarization level of the prototype is ?20 dB down from the co-polarization. Finally, the proposed antenna is applied in the DOA estimation for unequal power sources. Simulation results confirmed that the proposed antenna is effective and can be used in passive radar application.
Author(s): Y. Han, Q. Fang, L. Song, F. Yan, X. Qiao, S. Zhuang
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: On and Off-Body Radio Channel Performance of a Dual Band and Dual Mode Antenna
Abstract: In this paper, measurement results of onbody radio propagation channels at 2.45 GHz and offbody radio propagation channels at 1.9 GHz using dual band and dual mode (DBDM) antenna are presented. The proposed antenna works at two different frequencies with different radiation modes. Experiments are performed first in the chamber and then in an indoor environment. The path loss has been characterized for ten different on-body radio channels at 2.45 GHz. Five off-body radio channels are studied at 1.9 GHz. The path loss was modeled as a function of distance for onbody radio propagation at 2.45 GHz and off-body radio propagation at 1.9 GHz. For on-body propagation, the path loss exponent is noticed to be 2.48 and 2.22 in the camber and sensor laboratory, respectively. For offbody radio propagation case, the path loss exponent is noticed to be 1.27. The proposed antenna shows very good on-body and off-body radio propagation channel performance.
Author(s): M. M. Khan
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Ultra-wide Band Characteristic Basis Function Method and Best Uniform Approximation
Abstract: The ultra-wide band characteristic basis function method (UCBFM) is an efficient approach to calculate wideband radar cross section (RCS) of objects, but its calculation errors at lower frequency points are great and the reduced matrix at each frequency point needs to be reconstructed, which are very time-consuming. To solve these problems, an effective numerical method for fast calculating wideband RCS of objects by combining improved UCBFM (IUCBFM) and best uniform approximation is proposed. This method improves the construction of the ultra-wide band characteristic basis functions (UCBFs) through solving the secondary level characteristic basis functions (SCBFs). In consideration of the mutual coupling effects among sub-blocks, the improved UCBFs contain more current information characteristics, which greatly improve the calculation precision at lower frequency points. Moreover, to avoid the reconstruction of reduced matrix at each frequency point, the best uniform approximation technology is used to fast predict the surface current at any frequency point in the given frequency band and further realize the fast calculation of wideband RCS of objects. Compared with traditional UCBFM, the method in this paper significantly improves the calculation accuracy and efficiency. Numerical results demonstrate that the proposed method is accurate and efficient.
Author(s): W. Nie, Z. Wang
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: Geometrical Optics Based Path Loss Model for Furnished Indoor Environment
Abstract: This paper describes the Geometrical Optics (GO) based path loss model for indoor environment path loss prediction. Both Geometrical Optics based total rays model and direct ray path loss model were developed. Optimization was then conducted to improve both models in path loss prediction for case of Line-Of- Sight (LOS) indoor environment. Both Geometrical Optics based total rays model and direct ray model were optimized with log-distance-dependent expression using least-square approach. This log-distance-dependent expression includes all effects due to multiple reflection and all uncertainties which is distance-dependent. The path loss measurement was conducted in Division of Information Technology (DITSC), Universiti Putra Malaysia. Both models were optimized with measured path loss which was collected from DITSC. The value of correction factor and coefficient in additional expression for optimized GO were developed and presented in this paper. The optimized GO based modes ware validated at five buildings in Universiti Putra Malaysia by referring to the absolute mean error for its accuracy and effectiveness in path loss prediction. The optimized direct ray model shows the best accuracy compared with optimized total rays model, direct ray model and total rays model.
Author(s): E. M. Cheng, Z. Abbas, M. F. AbdulMalek, K. Y. Lee, K. Y. You, S. F. Khor, M. Afendi
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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Title: On the Transmitted Beam Degradation through FSS in the Working Band by Plane-wave Spectrum Computation and Evaluation
Abstract: In this paper, we implemented the combination of FDTD (Finite Difference Time Domain) and the plane-wave spectrum (PWS) algorithms, to evaluate beam transmission through frequency selective surface (FSS) in the near field region. The hybrid method takes advantage of the FDTD for the wideband analysis ability, and that of the PWS theory in the rapid recomposition for transmitted fields due to variable beam incidence. Consequently, it meets the need of beam transmission evaluation in the working band when the FSS is located among a serial of components, as in a millimeter Quasi-Optical (QO) instrument. After verifying the hybrid approach by results of other methods, we studied the degradations in the transmitted beams through an FSS design within the band of interest. The investigations are performed at the view of the transmission coefficient distributions in the PWS. It is found that the transmitted beam distortion is due to the non-flatness of the transmission coefficient distribution in the spectrum region covered by the beam incidence.
Author(s): M. Jin, M. Bai
File Type: Journal Paper
Issue:Volume: 31      Number: 9      Year: 2016
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