ACES Publication Search





There are 16 search results for:



Title: ACES Journal May 2018 Cover
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 2172 KB

Title: ACES Journal May 2018 Front/Back Matter
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 423 KB

Title: ACES Journal May 2018 Full
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 11220 KB

Title: Design of Wideband Filtering Power Dividers with Harmonic Suppression Based on the Parallel-Coupled Line Structures
Abstract: This paper presents a wideband filtering power divider with harmonic suppression. By embedding two coupled-line sections to each way of the conventional Wilkinson structure, four resonant modes excited by two coupled lines and one original mode of the Wilkinson structure are incorporated to improve the in-band filtering responses. In order to enhance the frequency selectivity, a pair of long open stubs are inserted between these coupled-line sections to produce a pair of transmission zeros on both sides of the passband. Meanwhile, two additional transmission zeros at the upper stopband can be introduced to broaden the bandwidth of the stopband. Moreover, a short open stub is installed at the input port, which can also introduce one transmission zero to enhance upper stopband rejection. Finally, a prototype of the wideband filtering power divider operating at the center frequency of 3 GHz is designed and fabricated. The measured results show a 15-dB bandwidth of 56%, an isolation better than 18-dB and a 35-dB wide stopband from 4.44 to 7.73 GHz.
Author(s): H. Zhang, Z. Zhong, W. Wu
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 2202 KB

Title: Study of Passive Chipless IR-UWB Indoor Positioning Based on Time-of-Arrival and Band-Notch
Abstract: In the paper, a passive and chipless IR-UWB indoor positioning system is proposed that follows the criteria of spectral and temporal joint identification. In the scenario of a 2D positioning, the system is coordinated by three anchors; a node can then be positioned by recognizing the pulseís time-of-arrival (TOA) and the pulseís band-notch in its backscattered spectrum. The model of the positioning system is established and the numerical analysis is committed in terms of a conceived positioning example. Results validate the system that the positioning is accurate, and the accuracy can be further improved by calibrating the value of TOA through the time offset made by the pulses backscattered by the anchor with and without band-notch, respectively.
Author(s): J. Liu
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1935 KB

Title: A Broadband CPW Fractal Antenna for RF Energy Harvesting
Abstract: A novel broadband CPW-fed 2-iteration fractal antenna based on the circular patch and the equilateral triangle slot is designed for RF energy harvesting. The simulated and measured results show that the proposed antenna offers an impedance bandwidth of 162% from 0.88 to 8.45 GHz and a peak gain of 8.7 dBi. Afterwards, the single-stage voltage multiplier rectifier with a T shape LC matching network to reduce the reflection losses is used to realize RF-to- DC conversion in energy harvesting; here, it is also integrated with the fractal antenna to form the rectenna. Accumulating RF power from 2G (GSM), 3G (the third generation), 4G-LTE and WLAN frequency-bands, the measured results across an optimized load resistor of 4.7-k omega show that the maximum rectenna efficiency is 51.8%, 46.1% and 45.08% at the center frequency of 2.4 GHz, 2.1 GHz and 1.9 GHz, respectively. Additionally, the measured peak conversion efficiency of the system is 24.03% at 2.4 GHz.
Author(s): X. Bai, J. Zhang, L. Xu, B. Zhao
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1902 KB

Title: Microstrip Reflectarray for Generation of Electromagnetic Waves with Beam Vorticity
Abstract: One type of orbital angular momentum (OAM) reflectarray antenna is presented to radiate the electromagnetic wave with beam vorticity. Microstrip double square loops are adopted as the element for the proposed reflectarray. Reflect phase of the elements with various sizes are analyzed by HFSS software with periodic boundary condition and Floquet mode. Then massive elements with different sizes are arranged helically to form the reflectarray, transforming the incident spherical wave into a vortex phase front. Several OAM reflectarray examples with different OAM mode and different feed mode are designed and fabricated. The phase patterns of far-zone field are simulated by FEKO software and measured by near-field scanning system, which demonstrates the phase singularity and vortex.
Author(s): H.-T. Chen, R. Pan, W.-Z. Sun, S.-Y. He
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 2068 KB

Title: Printable Chipless Tag and Dual-CP Reader for Internet of Things
Abstract: This paper proposes a printable chipless tag that encodes more bits than a conventional tag, and also a dual circularly polarized (CP) reader that achieves high isolation with insensitive orientation. To demonstrate this concept, a radio-frequency identification (RFID) tag of 13mm◊13mm is designed to encode 5 bits covering 6 - 9 GHz. This tag is investigated and measured with dual- CP backscattering characteristics for the first time. The versatile dual-CP reader, along with this tag which is feasible to print on other flexible substrate including papers, clothes and plastics, are promising to benefit the Internet of Things (IoT).
Author(s): G. Dong, Y. Shen, H. Meng, N. Chen, W. Dou, S. Hu
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1942 KB

Title: Adaptive Compensation Loop Control Method for Dynamic Range Wireless Power Transfer in Endoscopic Capsules Applications
Abstract: In this paper, an adaptive compensation loop control method is presented for dynamic range wireless power transfer (WPT) based wireless endoscopic capsules (WEC) applications. Rather than a fixed external resistor feedback network utilized in the DC-DC converter with maximum power point control (MPPC) capability, an enhanced nMOSFET based adaptive compensation loop is introduced to extract maximum power transfer from the RF-DC rectifier within overall operational power range of the WEC system. Simulation in ADS and measurement among three rectifiers with an LDO, a fixed external resistor feedback network and an adaptive compensation loop control are performed respectively to achieve a steady 3.3V on a resistive load of 100 omega, which validates that the proposed adaptive compensation loop control method realizes an extended dynamic power range with a lower limit of 21.5dBm to realize a minimum 100mW load DC power delivery for the IPT enabled WEC system.
Author(s): H. Zhang, Z. Zhong, W. Wu
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1856 KB

Title: Precision Loss Analysis and Its Solution in Calculation of Electromagnetic Wave Propagation in Reentry Plasma Sheath
Abstract: In this paper, the precision loss problem in calculation of EM wave propagation in the extreme reentry plasma sheath environment is analyzed. Furthermore, we propose a numerical calculation method with controllable precision to deal with this problem. The simulation results show the effect of computational precision loss on EM wave propagation in reentry plasma sheath and also illustrate the validity of the controllable precision calculation method.
Author(s): X. Chen, F. Shen, Y. Liu, W. Ai, X. Li
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1784 KB

Title: Post-processing Techniques for Polarimetric Passive Millimeter Wave Imagery
Abstract: Post-processing techniques for polarimetric passive millimeter wave (MMW) imagery are proposed to display imaging information comprehensively. Initially an image fusion method based on two-scale decomposition is proposed to realize polarimetric passive imagery fusion. The fusion rules are separately designed for base layer and detail layer to reconstruct weight maps. Then an improved technique for displaying polarization information through color is proposed to present polarization features simultaneously with unpolarized imagery. Experimental results demonstrate that the proposed post-processing techniques are capable of presenting more informative imagery.
Author(s): L. Wu, J. Q. Zhu , S. S. Peng, Z. L. Xiao, Y. K. Wang
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1755 KB

Title: Uncertainty Analysis of Reflection Coefficient for a Coating with Random Flaws Using Adaptive Mesh and DGTD Method
Abstract: An imperfect coating shall cause uncertainties in the analysis of electromagnetic properties. To quantify the influence of irregularity, complexity, and uncertainty of the coatings for electronic devices, an adaptive mesh algorithm combined with the discontinuous Galerkin time domain (AM-DGTD) method is developed. The uncertain variations are incorporated into the proposed algorithm by an appropriate parameterization. The standard statistical analysis is performed to calculate the appropriate moments, i.e., mean and variance. The developed method is validated by modeling a dielectric coating with uncertain flaws in an adaptive mesh grid. The computed quantities of interest from numerical estimations are compared with the analytical values, these results agree with the physical explanation, and are in good agreement with the exact values, as demonstrated by numerical experiments.
Author(s): H. Li, I. Hussain, Y. Wang, Q. Cao
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 2878 KB

Title: Resistive Active Balanced Power Divider Design with Touchstone and Kronís Formalism Hybrid Model
Abstract: A resistive active power divider (RAPWD) design based on Kronís model is introduced. The threeway RAPWD topology is essentially constructed with a low noise amplifier (LNA) with input and output matching shunt resistances. The RAPWD S-parameter is analytically expressed from the Kronís method hybridized with the LNA touchstone model. The RAPWD synthesis relation is established in function of the expected gain and matching access. The feasibility of the established Kronís method modelling is validated with a proof-ofconcept (POC) using the surface mounted monolithic LNA LEE-9+ from mini-circuits. As expected, S-parameters are in good correlation between simulations and computed results from the proposed hybrid method. A relatively flat transmission gain of about 9+/-0.2 dB is realized in the very wide frequency band 0.5 to 4.5 GHz. The broadband tested RAPWD input and output matching and access port isolations are widely better than 10 dB.
Author(s): B. Ravelo, F. Wan, S. Lallechere, B. Agnus
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1937 KB

Title: An Extension of Cooray-Rubinstein Formula on the Calculation of Horizontal Electric Field from Inclined Lightning Channel
Abstract: An approximate method to calculate the horizontal electric field from inclined lightning channel in frequency-domain was proposed based on the extension of Cooray formula and Cooray-Rubinstein formula. Validations of these two extended formulas were both performed by comparing their calculation results with those obtained by the numerical solution of Sommerfeldís integrals using Bannister approximations. The results have shown that both the accuracy of these two extended formulas are mainly related to the observation distance and the ground conductivity, and will increase with the increasing ground conductivity and observation distance. The extended Cooray formula could predict the horizontal electric field at ground level accurately at the distance beyond 100m. And the extended Cooray-Rubinstein formula could yield an acceptable approximation on the above-ground horizontal electric field with the exception of the observation point at close range under poor ground conductivity less than 0.0001S/m.
Author(s): H. Wan, X. Wang, Y. Chen, X. Pan, X. Lu
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1735 KB

Title: Drastic-Variation Condition of Electric Field and Its Applications in Microwave Heating
Abstract: Microwave heating usually leads to nonuniform temperatures due to the existence of drasticvariation of electric field. In this paper, a numerical method combined with integral equation and spectrum analysis is proposed to find its critical condition. Results show that the electric field is generally unstable, and a tiny shift in microwave frequency, permittivity of dielectric object or cavity geometrical parameters will produce a drastic variation in electric field distribution, moreover, the smallest shift of parameter can be obtained by the reverse search. FEM method is used to verify the conclusions. Finally, some supplements for the interest regarding practical applications are presented and analyzed.
Author(s): Z. Tang, S. Zhang, T. Hong, F. Chen, K. Huang
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 2109 KB

Title: Analysis and Suppression of EMI for Traction Control Unit Speed Sensors of CRH380BL Electric Multiple Unit
Abstract: The doors of China railways high-speed 380BL-type (CRH380BL) electric multiple unit (EMU) at Changchun station in China could not be opened. It was analysed that the traction control unit (TCU) speed sensors were disturbed by the pantograph-catenary arc while lowering the pantograph. To solve this problem, firstly, the electromagnetic interference (EMI) for the second train body (02TB) of CRH380BL EMU where the pantograph-catenary is located at is tested. The results show that the intensity of EMI in space is increased significantly because of the pantograph-catenary arc. The distribution of spectrum of EMI is generally random, but the spectrum is mainly distributed in the range from 5MHz to 10MHz. Based on the test results, the coupling mechanism of EMI for the TCU speed sensor is analyzed in this paper. Then a method of nesting magnetic rings on the shielded cable is proposed for suppression of the interference. It can reduce the EMI about 8dB at the main frequency bandwidth mentioned above with 12 centimeters long Ni-Zn ferrite magnetic rings.
Author(s): Y. Tang, F. Zhu, H. Lu, X. Li
File Type: Journal Paper
Issue:Volume: 33      Number: 5      Year: 2018
Download Link:Click here to download PDF     File Size: 1832 KB