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oe1(光电查) - 科学论文

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出版时间
  • 2019
  • 2018
研究主题
  • reconfigurable feed network
  • wideband
  • slot antenna
  • polarization reconfigurable antenna
  • reconfigurable filter
  • folded
  • ridged
  • multiband filter
  • quarter-mode
  • substrate integrated waveguide (SIW)
应用领域
  • Optoelectronic Information Science and Engineering
  • Electronic Science and Technology
机构单位
  • Nanjing University of Aeronautics and Astronautics
  • University of Alberta
96 条数据
?? 中文(中国)
  • Polarization Reconfigurable Corner Truncated Square Microstrip Array Antenna

    摘要: In this paper, a simple 2 × 2 polarization reconfigurable planar microstrip array antenna is presented. It is based on electrical switching technology using PIN diodes. Each element of the array is excited with the aid of the corporate feed technique. Each element of the proposed structure consists of a corner truncated square patch connected to parasitic triangular conductors by means of PIN diodes. The array element is configured to facilitate linear polarization (LP), right-hand circular polarization (RHCP) or left-hand circular polarization (LHCP) by means of 4 independently biased PIN diodes. The proposed antenna is designed and simulated using electromagnetic simulation software CST Microwave Studio. In order to experimentally validate the design, a prototype is fabricated on a 1.6 mm thick RT Duroid substrate of relative permittivity εr = 2.2. The performance of the antenna is validated experimentally using 16 PIN diodes. The simulation and measured results for all the polarization states of the array antenna are found to be in good agreement. The measured results have established the polarization reconfigurable ability of the antenna for 5.7–6.0 GHz operating band. The proposed antenna is suitable for C-band point-to-point communication applications.

    关键词: PIN diode switch,polarization reconfigurable,corporate feed network,reconfigurable antenna,Array antenna,circular polarization

    更新于2025-09-23 15:23:52

  • Low-loss and broadband non-volatile phase-change directional coupler switches

    摘要: An optical equivalent of the field-programmable gate array (FPGA) is of great interest to large-scale photonic integrated circuits. Previous programmable photonic devices relying on the weak, volatile thermo-optic or electro-optic effect usually suffer from a large footprint and high energy consumption. Phase change materials (PCMs) offer a promising solution due to the large non-volatile change in the refractive index upon phase transition. However, the large optical loss in PCMs poses a serious problem. Here, by exploiting an asymmetric directional coupler design, we demonstrate non-volatile PCM-clad silicon photonic 1 × 2 and 2 × 2 switches with a low insertion loss of ~1 dB and a compact coupling length of ~30 μm while maintaining a small crosstalk less than ?10 dB over a bandwidth of 30 nm. The reported optical switches will function as the building blocks of the meshes in the optical FPGAs for applications such as optical interconnects, neuromorphic computing, quantum computing, and microwave photonics.

    关键词: Silicon photonics,Non-volatile,Optical switches,Phase-change materials,Reconfigurable photonics,Integrated photonic devices

    更新于2025-09-23 15:23:52

  • Photothermal-Induced Self-Healable and Reconfigurable Shape Memory Bio-Based Elastomer with Recyclable Ability

    摘要: Photothermal-induced self-healable and shape memory materials have drawn much attention due to the rapidly growing technical applications and environmental requirements. As epoxy natural rubber (ENR) is a kind of bio-based elastomer with good mechanical properties, weather resistance, and air impermeability, it is of great significance to incorporate ENR with recyclable, photothermal-induced self-healable and shape memory properties. In this study, we report a simple method to cross-link ENR with dodecanedioic acids (DAs) through esterification reaction, and during the cross-linking process, a little aniline trimer (ACAT, a kind of oligoaniline) was added at the same time. Then, the ENR-DA-ACAT vitrimers that were covalently cross-linked with recyclable, self-healable, and multiple responsive properties were obtained, which also possessed various functions. As a result of the transesterification reactions at elevated temperatures, the ENR-based vitrimers possess the ability to be reprocessed and self-healed, and the mechanical properties could be maintained even after three consecutive breaking/mold pressing cycles. Besides, the vitrimer is also responsive to near-infrared (NIR) light and pH with the introduction of ACAT, and we also find that ACAT can be used as a catalyst to accelerate the transesterification reaction. Moreover, it is demonstrated that the ENR-DA-ACAT vitrimer could also be used to construct the reconfigurable shape memory polymer; the shape fixing ratio and shape recovery ratio are both above 95% in the reconfiguration process, and the multistage shape memory performance can also be achieved by NIR irradiation, which will potentially lead to a wide application for ENR in the field of actuators.

    关键词: self-healing,reconfigurable shape memory,photothermal effect,recyclable,transesterification reaction,ENR

    更新于2025-09-23 15:23:52

  • Electrically tuned microwave CP cross slot patch antenna using liquid crystal technology

    摘要: The rapid progress in material science and electronic technology is great possibility in designing reconfigurable wireless devices which are frequency tunable, flexible and consume low energy. In this paper, the anisotropic propriety of a new liquid crystal mixture 'GT3-23001' in their nematic phase are exploited for designing tunable circular polarized cross slot patch antenna for WLAN applications. Reconfiguration of frequency response is controlled through an electrical external command. The proposed reconfigurable antenna based on liquid crystal satisfies a continuous frequency tuning of 15.83% with a global bandwidth of around 467.92 MHz (19.5%). to validate this novel mixture of liquid crystal, the simulated results are compared with the measured data and a good agreement is noticed.

    关键词: liquid crystal mixture,Material science,tunable patch,circular polarized,reconfigurable,frequency tuning

    更新于2025-09-23 15:23:52

  • Reconfigurable metasurface lens based on graphene split ring resonators using Pancharatnam–Berry phase manipulation

    摘要: A reconfigurable graphene based metasurface is presented to controllably focus a circularly polarized incident plane wave. The unit cell of the proposed metasurface consists of split ring resonators on both sides of a dielectric layer. The required phase shift for focusing purpose is achieved by concurrent rotation of the elements to obey to the Pancharatnam–Berry concept. Convergence/Divergence of the transmitted wave can be controlled by handedness of the impinging plane wave and direction of the elements’ rotation. The operating frequency of the designed lens and its focal length can be adjusted by properly exploiting to the unique property of graphene, i.e. by tuning its chemical potential.

    关键词: metasurface,Graphene,Pancharatnam–Berry phase,reconfigurable lens

    更新于2025-09-23 15:23:52

  • [IEEE 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - Va?ster?s (2018.9.3-2018.9.6)] 2018 IEEE Conference on Antenna Measurements & Applications (CAMA) - Pattern Reconfigurable Antenna Using A Functional Material for MMW Application

    摘要: This paper introduces a novel reconfigurable antenna for controlling radiation beam direction by using integrated phase-change material (PCM). A PCM GeTe-based parasitic patch considered as a switchable element between insulator and conductive states is applied to operate with a driven patch radiator. The direction of the radiation pattern of the antenna can be tilted by changing the state of the GeTe-based patch from its insulator to conductive state. Obtained result shows that the proposed technique is effective to control the beam direction of the antenna. Around a 400 titled angle is achieved by the insulator-to-conductor activation of the GeTe patch which can be realized by an optical source, making the antenna simple and compact without extra bias circuit. Hence, the antenna is suitable for millimeter-wave applications.

    关键词: pattern reconfigurable,millimeter wave application,GeTe-based parasitic patch

    更新于2025-09-23 15:23:52

  • Pattern Reconfigurable Wideband Loop Antenna for Thorax Imaging

    摘要: A unidirectional loop antenna that can achieve wideband pattern re-configurability from -40 to +40 degrees in azimuth plane is presented. The antenna is designed to fulfill the multi-slice (level) scanning requirements of electromagnetic imaging (EMI) systems for thorax imaging. To overcome the need for positioning of several antenna-arrays, and hence eliminate the mutual coupling related complications, a square-loop antenna with reconfigurable pattern is designed. To create a unidirectional radiation, the loop is loaded with capacitive gaps, which convert its radiation mechanism to that of two virtual dipole arrays with quadrature phase excitation. By utilizing this feature, the location of the gaps are varied on the loop's structure to form virtual dipole arrays in different directions, thus rotating the radiation pattern without physically moving the structure of the antenna. As a proof of concept, six gaps were created on the loop and each gap is loaded with a PIN diode to electronically switch between the positions of the designed gaps, thus enabling changing the radiation direction. The proposed antenna can achieve a compact size of 0.32λ×0.32λ×0.002λ (λ is the wavelength of the lowest resonance of the antenna) and a wide fractional bandwidth of 32% at 0.8-1.15 GHz, with a peak gain and front-to-back-ratio of 2.1 dBi and 8 dB, respectively. The antenna is successfully tested on a thorax imaging platform to detect small volume of water (5 mL) inside lungs as an emulation of early pulmonary edema.

    关键词: unidirectional antenna,virtual dipole array,pattern reconfigurable antenna,loop antenna,Electromagnetic imaging,wideband antenna

    更新于2025-09-23 15:23:52

  • Design and implementation of a low profile polarization-reconfigurable transmitarray with linear polarized feed

    摘要: A novel polarization-reconfigurable transmitarray with linear polarized feed is presented in this letter. Each element in the proposed transmitarray consists of two cascaded cross dipoles to achieve more than 310° of linear phase with transmission magnitude equal to or better than 0.8 dB. The proposed unit cell has a thickness of 0.22λ0, which leads to a low profile transmitarray compared with those conventional designs. The element behavior of low transmission loss has resulted in higher antenna efficiency. By properly rotating the feed antenna around the center and selecting the x- and y-dimension of each element, the proposed transmitarray can generate radiation patterns with different polarization states, including left-handed circular polarization (LHCP), right-handed circular polarization (RHCP), and linear polarization(LP). For the purpose of validation, a double-layer center-fed 11 × 11-element transmitarray prototype is manufactured and tested at X-band. Measurement results demonstrate the designed transmitarray realize both high gain performance and multiple polarization operation.

    关键词: cross dipole,polarization reconfigurable,low profile,transmitarray

    更新于2025-09-23 15:23:52

  • [IEEE 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - Chengdu, China (2018.5.7-2018.5.11)] 2018 International Conference on Microwave and Millimeter Wave Technology (ICMMT) - A Novel Frequency Reconfigurable Coupling Microstrip Patch Antenna

    摘要: In this paper, a novel frequency reconfigurable coupling microstrip patch antenna is presented. A coplanar waveguide (CPW) feed line integrated on the ground plane is adopted in the structure to provide TM21 mode. Four PIN diodes are mounted on the patch gap to achieve frequency reconfiguration. By controlling the on-off state of PIN diodes electronically, resonant frequency points (5.75, 5.84, and 6.06 GHz) can be adjusted. What's more, a wide tunable range is achieved by loading more parasitic patch.

    关键词: coplanar waveguide feed,coupling,Patch antenna,frequency reconfigurable

    更新于2025-09-23 15:22:29

  • [IEEE 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Macau, Macao (2018.9.26-2018.9.28)] 2018 IEEE International Conference on RFID Technology & Application (RFID-TA) - Polarization Reconfigurable Antenna with Beam Steering Performance

    摘要: This paper proposed a novel method reconfiguring the polarization of the dielectric resonator antenna (DRA) with beam steering performance. During the process of liquid alteration between the two zones of the 3-D printed container, the proposed antenna performed with beam steering performance. What's more, the polarization was switched with the beam steering process. The proposed design is suitable for the application as a RFID reader.

    关键词: dielectric resonator antenna,Radio frequency identification (RFID),polarization reconfigurable,beam steering

    更新于2025-09-23 15:22:29