ACES Publication Search
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| Title: | ACES Journal July 2019 Cover |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 4059 KB |
| Title: | ACES Journal July 2019 Front/Back Matter |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1366 KB |
| Title: | ACES Journal July 2019 Full |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 14678 KB |
| Title: | A Succinct Explicit Local Time-Stepping Method for Helmholtz Wave Equation Based Discontinuous Galerkin Time Domain Method for 3-D Multiscale Electromagnetic Modeling |
| Abstract: | A succinct explicit local time-stepping (LTS) method for Helmholtz wave equation based discontinue Galerkin time domain method has been developed to analyze 3-D multiscale electromagnetic problems. In the proposed LTS scheme, a simple linear interpolation procedure is implemented to calculate the fields in the subdomain with the larger mesh size at the time steps corresponding to its neighboring subdomains with the smaller mesh size, and thus the proposed method can be easily generalized to the situation of the multiple subdomains with arbitrary time step ratio. With the proposed LTS method, the computational efficiency can be improved for the analysis of the multiscale problems. Several numerical examples including dielectric loaded resonance cavity, microstrip filter, and Vivaldi antenna are given to illustrate good performance of the proposed succinct explicit LTS method. |
| Author(s): | P. Wang, Y. Shi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 2611 KB |
| Title: | Improvement of Microwave Metamaterial Aperture Imager with Genetic Algorithm |
| Abstract: | The genetic algorithm is used to improve the imaging capability of the microwave metamaterial aperture imager operating at Ku-band. The microwave metamaterial aperture imager is made up of the complementary electric-LC elements and Jerusalem cross structures elements. Besides, the genetic algorithm is applied to optimize the array of the elements, which can reduce the average mutual coherence of the patterns of the microwave metamaterial aperture imager at different frequencies. Then, the patterns of the microwave metamaterial aperture imager is used for the image reconstruction experiments. From the image reconstruction results, it can be seen that the quality of the recovered image is improved. The performance of the microwave metamaterial aperture imager using the genetic algorithm is crucially enhanced and extensive simulations verify the effectiveness of the proposed improvement approaches. |
| Author(s): | S. Tian, L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1748 KB |
| Title: | The 3D Fractional Modeling of Electromagnetic Sub-Diffusion Based on FDTD |
| Abstract: | The anomalous diffusion has been discovered in many natural motions, it is defined as a phenomenon that does not conform to FICK's diffusion law. One of the anomalous diffusions is the electromagnetic subdiffusion, which indicated the power law decay rate is slower than normal -2/5. In this paper, we modeled electromagnetic sub-diffusion based on 3D finitedifferent time-domain (FDTD) method. Through the introduction of roughness parameter in the definition of conductivity and the discretization of fractional integrations, the electromagnetic sub-diffusion can be efficiently modeled. The improved method is verified by homogeneous half-space models and anomalous models with 3D bodies, the results show that it can model 3D electromagnetic sub-diffusion with high precisions and has a good performance in the recognitions of anomalous bodies. |
| Author(s): | X. Zhao, Y. Jiang, Y. Ji |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1430 KB |
| Title: | The Direction Switching Control of Electromagnetic Waves Based on All-dielectric Metamaterials |
| Abstract: | Electromagnetic waves control is becoming more and more urgent for important applications in communication and military fields. Studies have shown that it is possible to achieve reflection and refraction control of electromagnetic waves by introducing phase gradient. Wavefront control of electromagnetic waves can be achieved with metamaterials devices. However, metamaterials devices have to be diversified and enhance their capabilities to catch up the rapidly expanding demand on dynamic control currently. In this paper, we design a dynamic-modulated all-dielectric microwave control device to reconstruct the phase profile by filling different dielectric constants of media into it. As a result, the deflection direction of the electromagnetic waves, including whether the deflection occurs or not, can be controlled by this device flexibly. The device with such dynamic modulation function has potential application in the design and development of other functional devices or system, such as switches, beam shaping and imaging systems. |
| Author(s): | Y. Hua, K. Chen, Y. Fu, X. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1530 KB |
| Title: | A Dual-band WLAN Antenna with Reactive Loading |
| Abstract: | Dual-band antenna is very essential for multiple band communication systems like wireless local area network (WLAN) with lower and upper operating bands. In this paper, a dual-band antenna is proposed and analyzed for the WLAN applications. The proposed antenna fed by coplanar waveguide (CPW) consists of an L-shaped, reversed L-shaped strips and two inverted U-shaped loadings that are to implement the reactive characteristics. The reactive loadings can adjust the bandwidth and performance of the dual-frequency WLAN antenna that is verified by the simulation and measurement, respectively. The results demonstrate that the -10dB impedance bandwidth of the proposed dualband antenna can cover the two WLAN frequency bands from 2.4 GHz to 2.484 GHz and from 5.15 GHz to 5.35 GHz, respectively. Moreover, the proposed antenna has omnidirectional radiation patterns at the two operating bands. |
| Author(s): | Y. Xia, W. Xue, Y. Li, L. Zhao |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1525 KB |
| Title: | A Transmitarray Antenna with Double Conformal Rings as the Cell Elements |
| Abstract: | In this paper, we mainly study the electromagnetic transmission characteristics of transmission array antennas and transmission units. Based on array antenna theory and geometric theory, we construct a transmission array antenna for a double conformal rings (DCR). It works in a 10GHz two-layer transmission array. A double resonant conformal rings are used as the unit element. By changing the physical dimensions of the double conformal unit, phase coverage of up to 600° can be achieved. And the 1d B gain bandwidth is has by 7% compared to the previous transmission array. The simulated and measured peak gain is 27.59 dB and 25.91dB, respectively. |
| Author(s): | K. Yan, X. Lv, Z. Han, Y. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1627 KB |
| Title: | A Low-Profile Dual-Polarized Crossed Dipole Antenna on AMC Surface |
| Abstract: | A low-profile dual-polarized crossed dipole antenna on artificial magnetic conductor (AMC) surface is presented in this paper. The antenna consists of two orthogonal dipoles, a periodic arrangement of artificial magnetic conductors and a ground floor. The antenna has a section height of only 13mm (0.13λ0, λ0 is the wavelength in free space at 3 GHz). With utilizing the 6×6 unit cell of square patch based AMC, the antenna can achieve a wide band. To verify this design, a prototype of this antenna is designed, fabricated and measured. Measured results exhibit that bandwidth from 2.9 GHz to 3.32 GHz (S11< -10dB) for one port and from 2.995 GHz to 3.47 GHz (S22< -10dB) for another port are obtained, respectively. Meanwhile, the isolation between two ports is less than -30 dB, and stable radiation patterns are realized in operating frequency band. |
| Author(s): | R. He, Z.-H. Yan, Y.-B. Meng |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1460 KB |
| Title: | Low-Cost Miniaturized NFC Antenna Design for Mobile Phone |
| Abstract: | A low-cost and miniaturized NFC antenna design for mobile phone is proposed. Among all the phone antennas, NFC antenna is the biggest one, thus leading to higher manufacturing costs and adverse conditions for device integration. It is well known that four radiation sides are used in the traditional NFC antennas However, this letter presents a novel single side radiation slender NFC antenna structure, which well solves the adjacent sides reverse current interference through magnetic substrate selectivity laying in the traditional slender NFC antenna. This proposed structure can not only save magnetic substrate materials, but also significantly increase the radiation capacity through asymmetric structure design, and ultimately lead to a 38% increase in the communication performance. Simulation and experiment results verify that this simple design can significantly reduce the cost, suggesting a good prospect in practical use. |
| Author(s): | W. Li, D. Liang, L. Chen, L. Zhang, L. Deng |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1943 KB |
| Title: | A Low Frequency Ultra-Wideband Electrically Small Monopole Antenna for HF/VHF Application |
| Abstract: | In this paper, a low frequency ultra-wideband electrically small monopole antenna (ESMA) with a nonfoster circuit (NFC) loading for HF/VHF application is proposed. The devised ESMA has a very small height of 30 cm at 18 MHz, whose performance is severely limited due to the electrically small size characterized by large reactance and small radiation resistance. To conquer the limitation of the passive matching method, a NFC is developed and properly designed to cancel out the large reactance of ESMA and broaden the bandwidth. In this paper, the design principle is presented in detail for devising an ESMA system. At last, circuit and electromagnetism co-simulation is constructed to make the results more accurate and convinced. The simulated and measured results indicate that a -10 dB fractional bandwidth of 169% ranging from 18 MHz to 218 MHz is obtained for the designed ESMA matched by the NFC. |
| Author(s): | Y. Xia, W. Xue, Y. Li, W. Shi, B. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1799 KB |
| Title: | A Novel Frequency Reconfigurable Polarization Converter Based on Active Metasurface |
| Abstract: | In this paper, a novel frequency reconfigureable polarization converter (FRPC) based on active metasurface tuned by positive-intrinsic-negative (PIN) diodes is proposed. The metasurface unit cell of the FRPC consists of truncated metal square patches and bias lines, which are all etched on a substrate backed by a metal ground. On one hand, the FRPC can convert linearly polarized waves along the x- and y-axis into leftand right-hand circularly polarized waves from 5.13 to 5.61 GHz and from 5.37 to 6.72 GHz when all PIN diodes are turned ON and OFF, respectively. On the other hand, the proposed FRPC shows good angle stabilities when the incident angle ranges from 0° to 30° over the dual frequency bands. The simulated results show that the total 3 dB axial ratio relative bandwidth is more than 26%. To validate the polarization converter, a prototype of the FRPC is fabricated and measured. Measured results agree well with the simulation ones. |
| Author(s): | G. Liu, J. Han, X. Gao, H. Liu, L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1789 KB |
| Title: | A Novel Multi-Functional Electronically Tuned Polarization Converter Based on Reconfigurable Reflective Metasurface |
| Abstract: | In this paper, a novel multi-functional electronically tuned polarization converter based on reconfigurable reflective metasurface is proposed. The proposed polarizer can convert linearly polarized waves to left-hand circular polarization, right-hand circular polarization and crossed linear polarization waves without changing the polarization of incident waves. By controlling the varactors that mounted on the metasurface element, the reflection phase difference of the two orthogonal components of the incident linear polarization waves covers from -110° to 210° when the polarizer operates from 4.65 GHz to 5.35 GHz. Moreover, a 14 × 14 prototype is fabricated and measured to validate the proposed polarizer. Measured axial ratios agree well with the simulation results. |
| Author(s): | J. Han, G. Liu, Y. Mu, H. Liu, L. Li |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1529 KB |
| Title: | The Temperature Compensation for TE011 Mode Resonator with Bimetal Material |
| Abstract: | This paper proposes a temperature compensation design for TE011 mode resonator based on multiphysics analysis. The relationship between structure and electrical performance of circular waveguide resonator is specifically analyzed. Furthermore, a novel temperature compensation structure with bimetal material is proposed by using multiphysics analysis. The proposed TE011 mode resonator is fabricated and tested to verify the design method. The temperature drift coefficient of the compensated TE011 mode resonator can be dramatically reduced from 21.387 ppm/°C to 0.93ppm/°C. |
| Author(s): | Q. Wu, J. Zhang, Y. Yang, X. Shi |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1505 KB |
| Title: | Transient Electro-Thermal Analysis of a Common Source Amplifier Circuit with a Physics-based MOSFET Model |
| Abstract: | An algorithm that combines a common source amplifier with the physics-based metal-oxidesemiconductor field effect transistor (MOSFET) model is proposed. By solving the coupled drift-diffusion model equations with spectral element time-domain (SETD) method, the distribution of electron quasi-Fermi potential, hole quasi-Fermi potential and the potential inside the MOSFET is obtained. The corresponding current densities and electric intensities distributed in the device can be used to couple the heat conduction equation. Furthermore, the Kirchhoff laws should be satisfied when the MOSFET device is inserted in the circuit. The Newton-Raphson method is used to solve the nonlinear circuit equations due to the existence of semiconductor devices. The transient electro-thermal characteristics of a common source amplifier circuit have been analyzed, and the numerical results demonstrate the validity of the proposed method. |
| Author(s): | T. Pan, D. Ding, H. Li, X. Cheng |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1348 KB |
| Title: | Analysis of the Charge Collection Mechanism of the Diamond Based on a Multi-physics Method |
| Abstract: | Diamond is one of the most important wide-band-gap semiconductors for radiation detection and electronic device upgrading, however, for the lack of effective quantitative simulation method, the generation, recombination and movement of carriers in this material are still far from fully studied. In this paper, a multi-physics method for quantitative analysis of these complicated processes in diamond is established. Furthermore, charge collection process in a diamond detector with incident protons is quantitatively studied by using this method. It can be concluded that the influence of carrier lifetime on charge collection efficiency (CCE) is saturated when the value of carrier lifetime is greater than the characteristic time for carriers to cover the diamond device. The influence of electric field on CCE is saturated when the value of electric field strength is greater than 1 MV/m. By comparison of the simulated results and the theoretical results of an ideal case, good agreements have been acquired in both saturated electric field and unsaturated electric field conditions. All these results indicate that this method is useful for quantitative simulation and further optimization design of diamond detectors and other devices. |
| Author(s): | Y. Li, H. Xie, L. Liu, J. Zhang |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1666 KB |
| Title: | Geometrical Dependence in Fixtures for 2D Multipole Micromagnets Magnetization Pattering |
| Abstract: | Different approaches have been used for micro-magnets multipole magnetization like fixed micro-fixtures, thermomagnetic patterning or laser machining. With previous techniques, inversion of magnetic polarizations is only partially achieved. In this work, a preliminary design of the fixtures for micromagnets with 10, 100 and 1000 μm thickness is done. The magnetizing field dependence in respect to the geometrical parameter of the fixture is analyzed. Maps of the required current permit to pre-select an adequate pulse power source. An experimental test has been done in order to validate designs. Design recommendations to optimize the magnetizing field and to minimize the current, thus the heat, are given. |
| Author(s): | M. Martinez-Munoz, E. Diez-Jimenez, G. Villalba Alumbreros, M. Michalowski, A. Lastra-Sedano |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1782 KB |
| Title: | The Influence of Thermal Deformation on the AMB-rotor System of HTR-PM Helium Circulator |
| Abstract: | Helium circulator is the core component of High Temperature Reactor-Pebblebed Modules (HTRPM), and its rotor is supported by active magnetic bearings (AMBs). The windings of the motor and AMBs will generate a great deal of heat due to Ohmic loss, which increases the temperature of the circulator. The high temperature will cause the thermal deformation of AMB-rotor system, leading to the clearance change between rotor and AMBs. The AMB stiffness and inductive transducer sensitivity will be affected by the changed clearance, which decrease the stability of the AMB-rotor system. In this paper, through theoretical analysis and finite element analysis (FEA), the influence of thermal deformation on the AMB stiffness and transducer measurement is studied. The simulation and experiment for the AMB-rotor system in the circulator is carried out to explore the performance of AMB controllers and the influences of thermal deformation on the unbalanced response of the AMB-rotor system is analyzed. The theoretical calculations in this paper has general applications in the controller improvement of AMBs under clearance change and provides a reference for mechanical structure design and controller design of AMBs. |
| Author(s): | J. Yu, G. Du, H. Wang, Z. Sun, L. Zhao |
| File Type: | Journal Paper |
| Issue: | Volume: 34 Number: 7 Year: 2019 |
| Download Link: | Click here to download PDF File Size: 1871 KB |