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Electrically tunable liquid crystal coplanar waveguide stepped-impedance resonator Research Articles
Xingye Fan, Ruozhou Li, Jing Yan, Yuming Fang, Ying Yu,jing.yan@njupt.edu.cn,ying_yu_001@163.com
Frontiers of Information Technology & Electronic Engineering 2021, Volume 22, Issue 9, Pages 1270-1276 doi: 10.1631/FITEE.2000278
Keywords: 可调阶梯阻抗谐振器;液晶;共面波导
High-Temperature Target Recognition Based on Spectral Radiation Information
Fan Xueliang,Cheng Xiaofang,Xu Jun
Strategic Study of CAE 2004, Volume 6, Issue 6, Pages 57-62
Based on the principles of optics and radiometry, the imaging mathematical model is established and the factors of the contrast (signal-noise-ratio) of high-temperature target and the scenery are given. By analyzing not only the differences in spectral properties between objects in the scene, but also the CCD spectral response theoretically, a new method of enhancement of contrast is given. By optimizing the initial image capture stage, using liquid crystal light valve to make a simple modification of the imaging system, the goal of high object recognition is achieved. The experimental results agree with the theoretical predicts.
Keywords: video image object recognition radiation information liquid crystal light valve
Ionic Elastomers for Electric Actuators and Sensors Review
Chenrun Feng, C.P. Hemantha Rajapaksha, Antal Jákli
Engineering 2021, Volume 7, Issue 5, Pages 581-602 doi: 10.1016/j.eng.2021.02.014
In the past decades, ion conductive polymers and elastomers have drawn worldwide attention for their advanced functions in batteries, electroactive soft robotics, and sensors. Stretchable ionic elastomers with dispersed soft ionic moieties such as ionic liquids have gained remarkable attention as soft sensors, in applications such as the wearable devices that are often called electric skins. A considerable amount of research has been done on ionic-elastomer-based strain, pressure, and shear sensors; however, to the best of our knowledge, this research has not yet been reviewed. In this review, we summarize the materials and performance properties of engineered ionic elastomer actuators and sensors. First, we review three classes of ionic elastomer actuators—namely, ionic polymer metal composites, ionic conducting polymers, and ionic polymer/carbon nanocomposites—and provide perspectives for future actuators, such as adaptive four-dimensional (4D) printed systems and ionic liquid crystal elastomers (iLCEs). Next, we review the state of the art of ionic elastomeric strain and pressure sensors. We also discuss future wearable strain sensors for biomechanical applications and sports performance tracking. Finally, we present the preliminary results of iLCE sensors based on flexoelectric signals and their amplification by integrating them with organic electrochemical transistors.
Keywords: Soft robots Ionic electroactive elastomer Ionic elastomer sensor Programmable deformation Liquid crystal elastomer
Xin Yu Wu,Fengshuo Wan,Hongyuan Feng,Shichao Jin,Chong Guo,Yu Wei,Dunge Liu,Yuqian Yang,Longzhu Cai,Zhi Hao Jiang,Wei Hong
Engineering 2024, Volume 32, Issue 1, Pages 70-82 doi: 10.1016/j.eng.2023.08.013
This paper presents a systematic investigation and demonstration of a K-band circularly polarized liquid-crystal-based phased array (LCPA), including the design, over-the-air (OTA) in-array calibration, and experimental validation. The LCPA contains 16 phase-shifting radiating channels, each consisting of a circularly polarized stacked patch antenna and a liquid-crystal-based phase shifter (LCPS) based on a loaded differential line structure. Thanks to its slow-wave properties, the LCPS exhibits a maximum phase-shifting range of more than 360° with a figure of merit of 78.3°·dB−1 based on a liquid crystal layer with a thickness of only 5 μm. Furthermore, an automatic OTA calibration based on a state ergodic method is proposed, which enables the extraction of the phase–voltage curve of every individual LCPA channel. The proposed LCPA is manufactured and characterized with a total profile of only 1.76 mm, experimentally demonstrating a scanned circularly polarized beam from −40° to +40° with a measured peak gain of 12.5 dBic and a scanning loss of less than 2.5 dB. The bandwidth of the LCPA, which satisfies the requirements of port reflection (|S11|) < −15 dB, an axial ratio (AR) < 3 dB, beam squinting < 3°, and a gain variation < 2.2 dB, spans from 25.5 to 26.0 GHz. The total efficiency is about 34%, which represents a new state of the art. The use of the demonstrated low-profile LCPA to support circularly polarized scanning beams, along with the systematic design and calibration methodology, holds potential promise for a variety of millimeter-wave applications.
Keywords: Circularly polarized Liquid crystal Liquid-crystal-based phased array (LCPA) Phase shifter Over-the-air (OTA) calibration
Title Author Date Type Operation
Electrically tunable liquid crystal coplanar waveguide stepped-impedance resonator
Xingye Fan, Ruozhou Li, Jing Yan, Yuming Fang, Ying Yu,jing.yan@njupt.edu.cn,ying_yu_001@163.com
Journal Article
High-Temperature Target Recognition Based on Spectral Radiation Information
Fan Xueliang,Cheng Xiaofang,Xu Jun
Journal Article
Ionic Elastomers for Electric Actuators and Sensors
Chenrun Feng, C.P. Hemantha Rajapaksha, Antal Jákli
Journal Article