Journal articles: 'Thin film antennas'

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Zhou, K. P., Y. T. Niu, W. N. Liu, Z. D. Wang, S. H. Guo, B. Li, Z. Wang, and X. K. Zhao. "Study and Analysis of a Multilayer Multipair Electret-Based Thin-Film Mechanical Antenna." International Journal of Antennas and Propagation 2021 (November 26, 2021): 1–18. http://dx.doi.org/10.1155/2021/3646425.

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Very low-frequency (VLF) and ultralow-frequency (ULF) electromagnetic waves have the advantage of high penetration and low propagation loss in wireless communication systems and are mainly used for underwater and underground communications, as well as for earthquake and lightning forecasting. At present, VLF and ULF antennas are mostly bulky and require hundreds of antennas and more to be set up, which is costly and inefficient. In this paper, we propose to generate VLF and ULF signals by rotating a multilayer multipair electret thin-film electret driven by an excitation device, which improves the problem of low radiation efficiency of VLF and ULF signals and the large size of conventional low-frequency transmitting antennas. Based on a multilayer, multipair electret film mechanical antenna, a magnetic field propagation model is developed, and the relationship between the magnetic flux density mode and the number of layers of electret films, as well as the relationship between the antenna emission frequency and the motor rotation frequency and the number of pairs of electret films, is analyzed. The selection of a suitable model for practical situations based on conditions such as antenna size and propagation distance is illustrated. The research work is of great importance for guiding the design of mechanical antennas and optimizing antenna structures.

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Lancaster, M. J., H. Y. Wang, and Jia-Sheng Hong. "Thin-film HTS planar antennas." IEEE Transactions on Appiled Superconductivity 8, no. 4 (1998): 168–77. http://dx.doi.org/10.1109/77.740682.

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Puchades, Ivan, Jamie E. Rossi, Cory D. Cress, Eric Naglich, and Brian J. Landi. "Carbon Nanotube Thin-Film Antennas." ACS Applied Materials & Interfaces 8, no. 32 (August 4, 2016): 20986–92. http://dx.doi.org/10.1021/acsami.6b05146.

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Tu, Cheng, Zhao-Qiang Chu, Benjamin Spetzler, Patrick Hayes, Cun-Zheng Dong, Xian-Feng Liang, Huai-Hao Chen, et al. "Mechanical-Resonance-Enhanced Thin-Film Magnetoelectric Heterostructures for Magnetometers, Mechanical Antennas, Tunable RF Inductors, and Filters." Materials 12, no. 14 (July 13, 2019): 2259. http://dx.doi.org/10.3390/ma12142259.

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The strong strain-mediated magnetoelectric (ME) coupling found in thin-film ME heterostructures has attracted an ever-increasing interest and enables realization of a great number of integrated multiferroic devices, such as magnetometers, mechanical antennas, RF tunable inductors and filters. This paper first reviews the thin-film characterization techniques for both piezoelectric and magnetostrictive thin films, which are crucial in determining the strength of the ME coupling. After that, the most recent progress on various integrated multiferroic devices based on thin-film ME heterostructures are presented. In particular, rapid development of thin-film ME magnetometers has been seen over the past few years. These ultra-sensitive magnetometers exhibit extremely low limit of detection (sub-pT/Hz1/2) for low-frequency AC magnetic fields, making them potential candidates for applications of medical diagnostics. Other devices reviewed in this paper include acoustically actuated nanomechanical ME antennas with miniaturized size by 1–2 orders compared to the conventional antenna; integrated RF tunable inductors with a wide operation frequency range; integrated RF tunable bandpass filter with dual H- and E-field tunability. All these integrated multiferroic devices are compact, lightweight, power-efficient, and potentially integrable with current complementary metal oxide semiconductor (CMOS) technology, showing great promise for applications in future biomedical, wireless communication, and reconfigurable electronic systems.

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Khan, Osama, Johannes Meyer, Klaus Baur, Saeed Arafat, and Christian Waldschmidt. "Aperture coupled stacked patch thin film antenna for automotive radar at 77 GHz." International Journal of Microwave and Wireless Technologies 11, no. 10 (June 10, 2019): 1061–68. http://dx.doi.org/10.1017/s1759078719000795.

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AbstractA hybrid thin film multilayer antenna for automotive radar is presented in this work. A 2 × 8 aperture coupled stacked patch antenna array is realized on a single layer printed circuit board (PCB) using a novel thin film-based approach. Using a compact 180° phase difference power divider, inter-element spacing in a 2×2 sub-array is reduced. Measurement results show a 19% (67.9–82.5 GHz) impedance bandwidth and a wideband broadside radiation pattern, with a maximum gain of 15.4 dBi realized gain at 72 GHz. The presented antenna compares favorably with other multilayer PCB antennas in terms of performance, with the advantage of simpler manufacturing and robust design. The antenna can be employed in mid-range automotive radar applications.

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Wang, H. Y., and M. J. Lancaster. "Aperture-coupled thin-film superconducting meander antennas." IEEE Transactions on Antennas and Propagation 47, no. 5 (May 1999): 829–36. http://dx.doi.org/10.1109/8.774137.

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Suzuki, N., K. Itoh, Y. Nagai, and O. Michikami. "Electromagnetically coupled superconductive thin-film small antennas." Physica B: Condensed Matter 194-196 (February 1994): 129–30. http://dx.doi.org/10.1016/0921-4526(94)90394-8.

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Patil, Deepak Rajaram, Ajeet Kumar, and Jungho Ryu. "Recent Progress in Devices Based on Magnetoelectric Composite Thin Films." Sensors 21, no. 23 (November 30, 2021): 8012. http://dx.doi.org/10.3390/s21238012.

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The strain-driven interfacial coupling between the ferromagnetic and ferroelectric constituents of magnetoelectric (ME) composites makes them potential candidates for novel multifunctional devices. ME composites in the form of thin-film heterostructures show promising applications in miniaturized ME devices. This article reports the recent advancement in ME thin-film devices, such as highly sensitive magnetic field sensors, ME antennas, integrated tunable ME inductors, and ME band-pass filters, is discussed. (Pb1−xZrx)TiO3 (PZT), Pb(Mg1/3Nb2/3)O3-PbTiO3 (PMN-PT), Aluminium nitride (AlN), and Al1−xScxN are the most commonly used piezoelectric constituents, whereas FeGa, FeGaB, FeCo, FeCoB, and Metglas (FeCoSiB alloy) are the most commonly used magnetostrictive constituents in the thin film ME devices. The ME field sensors offer a limit of detection in the fT/Hz1/2 range at the mechanical resonance frequency. However, below resonance, different frequency conversion techniques with AC magnetic or electric fields or the delta-E effect are used. Noise floors of 1–100 pT/Hz1/2 at 1 Hz were obtained. Acoustically actuated nanomechanical ME antennas operating at a very-high frequency as well as ultra-high frequency (0.1–3 GHz) range, were introduced. The ME antennas were successfully miniaturized by a few orders smaller in size compared to the state-of-the-art conventional antennas. The designed antennas exhibit potential application in biomedical devices and wearable antennas. Integrated tunable inductors and band-pass filters tuned by electric and magnetic field with a wide operating frequency range are also discussed along with miniaturized ME energy harvesters.

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Cai, Longzhu, and Qiushi Yu. "Comparison of Metallization Schemes on Glass Dielectrics for X-Band Glass Antennas and Energy Harvesting." Materials 14, no. 23 (November 28, 2021): 7283. http://dx.doi.org/10.3390/ma14237283.

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We prepare and test four types of glass antennas for X-band applications and energy harvesting. These antennas are made of three different glass metallization schemes, including conductive copper foil (CCF), conductive silver paste (CSP) and indium tin oxide (ITO) thin film. Compared with conventional microstrip patch antennas, the dielectric substrate materials of these designs are replaced with silicon-boron glass (εr = 6, tangent δ = 0.002). The antenna with CCF as a radiator and ground plane (case one) is compared with the antenna with ITO replacing the radiator (case two) and ground plane (case three), respectively, and the glass antenna made of CSP (case four) is also presented. In this paper, these four types of glass antennas are measured and analyzed, and a comparison of the fabrication process and performance of these antennas is demonstrated. This study could contribute to the development of human-machine interactivity (HMI) systems with glass dielectric substrates.

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Amram Bengio, E., Damir Senic, Lauren W. Taylor, Robert J. Headrick, Michael King, Peiyu Chen, Charles A. Little, et al. "Carbon nanotube thin film patch antennas for wireless communications." Applied Physics Letters 114, no. 20 (May 20, 2019): 203102. http://dx.doi.org/10.1063/1.5093327.

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Shimizu, Takashi, Yasuhiko Abe, Yoshizumi Yasuoka, and Kenji Gamo. "Thin-Film Slot Antennas for 2.5 THz Submillimeter Radiation." Japanese Journal of Applied Physics 35, Part 2, No. 2B (February 15, 1996): L266—L268. http://dx.doi.org/10.1143/jjap.35.l266.

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Burford, Nathan, and Magda El-Shenawee. "Computational modeling of plasmonic thin-film terahertz photoconductive antennas." Journal of the Optical Society of America B 33, no. 4 (March 25, 2016): 748. http://dx.doi.org/10.1364/josab.33.000748.

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Ohnimus, Florian, Uwe Maaß, Gerhard Fotheringham, Brian Curran, Ivan Ndip, Thomas Fritzsch, Jürgen Wolf, Stephan Guttowski, and Klaus-Dieter Lang. "Design and Comparison of 24 GHz Patch Antennas on Glass Substrates for Compact Wireless Sensor Nodes." International Journal of Microwave Science and Technology 2010 (February 7, 2010): 1–9. http://dx.doi.org/10.1155/2010/535307.

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Three patch antennas suitable for integration and operation in a compact 24 GHz wireless sensor node with radar and communication functions are designed, characterized, and compared. The antennas are manufactured on a low loss glass wafer using thin film (BCB/Cu) wafer level processing (WLP) technologies. This process is well suited for 3D stacking. The antennas are fed through a microstrip line underneath a ground plane coupling into the patch resonator through a slot aperture. Linear polarization (LP), dual mode (DM) operation, and circular polarization (CP) are achieved through the layout of the slot aperture and rectangular patch dimensions. Antenna gain values of ∼5.5 dBi are obtained in addition to the 10 dB impedance bandwidths of 900 MHz and 1.3 GHz as well as 500 MHz CP bandwidth with a 3 dB axial ratio for the LP, DM, and CP patch antennas, respectively.

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14

Jeong, Young-Gyun, Hannes Bernien, Ji-Soo Kyoung, Hyeong-Ryeol Park, Hyun‑Sun Kim, Jae-Wook Choi, Bong-Jun Kim, Hyun-Tak Kim, Kwang Jun Ahn, and Dai-Sik Kim. "Electrical control of terahertz nano antennas on VO_2 thin film." Optics Express 19, no. 22 (October 10, 2011): 21211. http://dx.doi.org/10.1364/oe.19.021211.

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15

Saijo, Hitoshi, Masahiko Morimoto, Toshihiko Kiwa, and Masayoshi Tonouchi. "Terahertz emission properties from YBCO thin film log-periodic antennas." Physica C: Superconductivity 362, no. 1-4 (September 2001): 319–23. http://dx.doi.org/10.1016/s0921-4534(01)00696-7.

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CZEKAJ, DIONIZY, and AGATA LISIŃSKA-CZEKAJ. "INFLUENCE OF Mg-DOPING ON SYNTHESIS OF SOL–GEL DERIVED BST THIN FILMS." Journal of Advanced Dielectrics 02, no. 01 (January 2012): 1250010. http://dx.doi.org/10.1142/s2010135x12500105.

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Solid solutions of Ba 1-x Sr x TiO 3 (BST) type are very attractive for application in information technology, but also in microwaves for such electrically controlled devices as phase shifters, tunable filters, steerable antennas, varactors, etc. In the present study thin films of a BST solid solution with x = 0.4 (BST60/40) were prepared by the sol–gel-type chemical solution deposition method. The influence of y = 1, 3 and 5 mol.% MgO doping on synthesis of BST60/40 thin films was studied. Thermal analysis both differential and thermogravimetric were used to determine the thermochemical properties of dried BST60/40– MgO gel powders. A multilayer spin-coating approach was utilized for the Ba0.6Sr0.4TiO3–MgO thin film deposition on stainless steel substrates. X-ray diffraction analysis, SEM and EDS were utilized for thin film characterization in terms of its crystalline structure, microstructure and chemical composition. Raman spectroscopy investigation of MgO -doped Ba0.6Sr0.4TiO3 thin films grown on stainless steel substrates were also performed within the wavenumber range k = 40–1070 cm-1.

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Lovat, G., P. Burghignoli, R. Araneo, and S. Celozzi. "Ultrasubwavelength Ferroelectric Leaky Wave Antenna in a Planar Substrate-Superstrate Configuration." International Journal of Antennas and Propagation 2014 (2014): 1–9. http://dx.doi.org/10.1155/2014/193690.

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The possibility of achieving directive fan-beam radiation with planar Fabry-Pérot cavity antennas constituted by an upper ferroelectric thin film and a lower ground plane having ultrasubwavelength thickness is studied by means of a simple transverse-equivalent-network approach and a cylindrical leakywave analysis, deriving simple design formulas. The performance of the proposed antenna is investigated in terms of power density radiated at broadside and directivity in the principal planes, pointing out the main limitations and tradeoffs associated with the reduced thickness.

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Yang, Jin-Kyu, and Hyeon-Seok Jeong. "Switchable Metasurface with VO2 Thin Film at Visible Light by Changing Temperature." Photonics 8, no. 2 (February 18, 2021): 57. http://dx.doi.org/10.3390/photonics8020057.

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We numerically demonstrated switchable metasurfaces using a phase change material, VO2 by temperature change. The Pancharatnam–Berry metasurface was realized by using an array of Au nanorods on top of a thin VO2 film above an Au film, where the optical property of the VO2 film is switched from the insulator phase at low temperature to the metal phase at high temperature. At the optimal structure, polarization conversion efficiency of the normal incident light is about 75% at low temperature while that is less than 0.5% at high temperature in the visible region (λ∼ 700 nm). Various functionalities of switchable metasurfaces were demonstrated such as polarization conversion, beam steering, Fourier hologram, and Fresnel hologram. The thin-VO2-film-based switchable metasurface can be a good candidate for various switchable metasurface devices, for example, temperature dependent optical sensors, beamforming antennas, and display.

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Tonouchi, M., H. Saijo, M. Hangyo, O. Morikawa, P. Gu, M. Tani, and K. Sakai. "Highly efficient terahertz radiation from YBa2Cu3O7−δ thin film log-periodic antennas." Physica C: Superconductivity 357-360 (August 2001): 1600–1602. http://dx.doi.org/10.1016/s0921-4534(01)00561-5.

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20

Cai. "An On-Glass Optically Transparent Monopole Antenna with Ultrawide Bandwidth for Solar Energy Harvesting." Electronics 8, no. 9 (August 21, 2019): 916. http://dx.doi.org/10.3390/electronics8090916.

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An on-glass optically transparent monopole antenna with ultrawide bandwidth is presented in this work, and the proposed antenna is of ring shape and coplanar waveguide fed structure. Optically transparent indium tin oxide (ITO) thin film with a thickness of ~160 nm is used as the conductive layer, which is sputtered on an optically transparent glass substrate. An impedance bandwidth of 6 GHz from 1 to 7 GHz is achieved, with a return loss lower than −10 dB, meaning a fractional bandwidth of 150%. The proposed antenna exhibits reasonable radiations of omni-directionality in the H plane and bi-directionality in the E plane. Like other transparent antennas discussed in literature, the antenna gain is relatively low (−4 dBi at 5 GHz). In order to optimize the antenna performance, multi-film approach is proposed to reduce its sheet resistance, and the result shows that the antenna gain at 4 GHz can be improved from −8 dBi to 5 dBi when optimizing the sheet resistance from 10 Ω/sq to 0.01 Ω/sq. The designed antenna possesses a high optical transparency, which makes it easy to integrate to the surface of windows or display panels, and it can be applied for solar energy harvesting and many other ultra-wideband applications, with little chance of detection.

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Mujahidin, Irfan, and Akio Kitagawa. "CP Antenna with 2 × 4 Hybrid Coupler for Wireless Sensing and Hybrid RF Solar Energy Harvesting." Sensors 21, no. 22 (November 20, 2021): 7721. http://dx.doi.org/10.3390/s21227721.

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The main challenge faced by RF energy harvesting systems is to supply relatively small electrical power to wireless sensor devices using microwaves. The solution is to implement a new device in a circularly polarized rectenna with circular polarization sensitivity integrated with a thin-film solar cell. Its dual-feed antennas are connected to a 2 × 4 asymmetric hybrid coupler and a multi-stage voltage doubler rectifier circuit. This configuration has a 2 × 4 asymmetric hybrid coupler used to produce 4 outputs with a 90-degree waveform phase difference. The two ports can independently be connected to the wireless sensor circuit: radiofrequency harvesting of hybrid energy solar and information equipment can be carried out with these two antennas. The Dual-Feed circular patch antenna has a two-port bandwidth of 137 MHz below −15 dB and an axial ratio of less than 3 dB, with a center frequency of 2.4 GHz with directional radiation and a high gain of 8.23 dB. It can be sensitive to arbitrary polarization of the input voltage multiplier waveform to overcome uncertainty in empirical communication environments. A parallel structure is arranged with a thin film solar cell integration from the transmitter with an output voltage of 1.3297 V with a compact composition and RF energy. The importance of adopting a wireless sensor strategy with circular polarization sensitivity and integrated RF solar energy harvesting rather than a single source method makes this research a significant novelty by optimizing the analysis of multiple wireless sensor signal access.

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Lin, Yu-Ming, Hung-Wei Wu, Yung-Wei Chen, Cheng-Yuan Hung, Shoou-Jinn Chang, and Yan-Kuin Su. "A Novel Transparent Microwave Thin Film Coating Technique Applied to Dual-Band Antennas." Electronic Materials Letters 15, no. 6 (October 1, 2019): 680–85. http://dx.doi.org/10.1007/s13391-019-00171-6.

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Abe, Yasuhiko, and Yoshizumi Yasuoka. "Operating properties of thin-film slot antennas at 2.5-THz submillimeter wave band." Electronics and Communications in Japan (Part II: Electronics) 85, no. 11 (October 23, 2002): 8–15. http://dx.doi.org/10.1002/ecjb.10053.

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Yeo, Junho, Sang-Gook Moon, and Jae-Young Jung. "Antennas for a battery-assisted RFID tag with thin and flexible film batteries." Microwave and Optical Technology Letters 50, no. 2 (February 2008): 494–98. http://dx.doi.org/10.1002/mop.23127.

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25

Koutsoukis, Grigorios, Ivan Alic, Antonios Vavouliotis, Ferry Kienberger, and Kamel Haddadi. "Roll-to-Roll In-Line Implementation of Microwave Free-Space Non-Destructive Evaluation of Conductive Composite Thin Layer Materials." Applied Sciences 11, no. 1 (January 2, 2021): 378. http://dx.doi.org/10.3390/app11010378.

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A free-space microwave nondestructive testing and evaluation module is developed for the low-power, non-ionizing, contactless, and real-time characterization of doped composite thin-film materials in an industrial context. The instrumentation proposed is built up with a handled vector network analyzer interfaced with corrugated horn antennas to measure the near-field complex reflection S11 of planar prepreg composite materials in a roll-to-roll in-line production line. Dedicated modeling and calibrations routines are developed to extract the microwave conductivity from the measured microwave signal. Practical extraction of the radiofrequency (RF) conductivity of thin film prepreg composite materials doped with nano-powders is exemplary shown at the test frequency of 10 GHz.

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Chkalov, Ruslan, Dmitriy Kochuev, Kirill Khorkov, and Valery Prokoshev. "Fabrication of bicomponent nanoantennas interfaces by femtosecond laser ablation method." EPJ Web of Conferences 220 (2019): 03008. http://dx.doi.org/10.1051/epjconf/201922003008.

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The work is devoted to the problem of fabrication interfaces of bicomponent nanoantennas. The possibility of using controlled laser ablation technology for the formation of thin-film elements is described. The applicability of the approach for rapid prototyping of various geometric configurations of optical antennas interfaces is shown.

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Michalik, Damian Arkadiusz, Paweł S. Jung, Bartłomiej W. Klus, Andrzej Kowalik, Anna Rojek, Urszula A. Laudyn, and Mirosław A. Karpierz. "Chromium plasmonic polarizer for high intensity light." Photonics Letters of Poland 9, no. 3 (September 30, 2017): 76. http://dx.doi.org/10.4302/plp.v9i3.767.

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In this work, we investigate a thin-film polarizer for a high intensity of the electromagnetic (EM) beam based on Cr nano wire arrays. Commonly used thin-film polarizing components are very sensitive for high power of EM waves and can be easily damaged by focused beams. The solution to this problem could be the thin-film polarizer based on metallic subwavelengths structures. This type of optical element has huge resistance comparing to typical thin-film polarizers. However, designing such an optical element for proper wavelength of EM wave and transmissions is not easy task. In this paper we present numerical as well as experimental results for specially designed chromium thin-film polarizer for wavelength 532nm Full Text: PDF ReferencesW. Zhou, K. Li, C. Song, P. Hao, M. Chi, M. Yu and Y. Wu, "Polarization-independent and omnidirectional nearly perfect absorber with ultra-thin 2D subwavelength metal grating in the visible region", Opt. Express 23, 11 (2015). CrossRef W. L. Barnes, A . Dereux, and T. W. Ebbesen, "Surface plasmon subwavelength optics", Nature 424, 824-830 (2003). CrossRef C. Lee, E. Sim, D. Kim, "Blazed wire-grid polarizer for plasmon-enhanced polarization extinction: design and analysis", Opt. Express 25, 7 (2017). CrossRef A. Lehmuskero, Metallic thin film structures and polarization shaping gratings (University of Eastern Finland 2010).Y. Leroux, J. C. Lacroix, C. Fave, V. Stockhausen, N. Felidj, J. Grandm, A. Hohenau, J. R. Krenn, "Active plasmonic devices with anisotropic optical response: a step toward active polarizer", Nano Lett. 5, 9 (2009). CrossRef R. T. Perkins, D. P. Hansen, E. W. Gardner, J. M. Thorne, A. A. Robbins, Broadband wire grid polarizer for the visible spectrum, US 6122103 (2000). DirectLink D. M. Sullivan, Electromagnetic simulation using the FDTD method, New York: IEEE Press Series (2000). CrossRef J. P. Berenger, Perfectly Matched Layer (PML) for Computational Electromagnetics, Morgan & Claypool Publishers (2007). CrossRef Yu, W., and R. Mittra, "A conformal FDTD software package modeling antennas and microstrip circuit components", IEEE Antennas Propagat. Magazine 42, 28 (2000) . CrossRef L. W. Bos, D. W. Lynch, "Optical Properties of Antiferromagnetic Chromium and Dilute Cr-Mn and Cr-Re Alloys", Phys. Rev. Sect. B, 2, 4267 (1970). CrossRef

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Ren, Xiansong, Zhaoyu Ji, Binkai Chen, Jing Zhou, Zeshi Chu, and Xiaoshuang Chen. "Carbon Nanotube Far Infrared Detectors with High Responsivity and Superior Polarization Selectivity Based on Engineered Optical Antennas." Sensors 21, no. 15 (July 31, 2021): 5221. http://dx.doi.org/10.3390/s21155221.

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Single-wall carbon nanotube (SWCNT) thin films are promising for sensitive uncooled infrared detection based on the photothermoelectric effect. The SWCNT film is usually shaped into a belt and diversely doped to form a p-n junction at the center. Under the illumination of a focused incident light, the temperature gradient from the junction to the contacts leads to photoresponse. When the SWCNTs are aligned in one direction, the photoresponse becomes polarization selective. Although a typical bowtie antenna can improve the responsivity and polarization extinction ratio by deep-subwavelength light focusing, the absolute absorptance of the junction region is only 0.6%. In this work, the antenna was engineered for a higher light coupling efficiency. By integrating a bottom metal plane at a specific distance from the SWCNT film and optimizing the antenna geometries, we achieved ultra-efficient impedance matching between the antenna and the SWCNTs, thus the absorptance of the junction region was further enhanced by 21.3 times and reached 13.5%, which is more than 3 orders of magnitude higher than that of the device without the engineered antenna. The peak responsivity was further enhanced by 19.9 times and responsivity reached 1500 V/W at 1 THz. The resonant frequency can be tuned by changing the size of the antenna. Over the frequency range of 0.5 THz to 1.5 THz, the peak responsivity was further enhanced by 8.1 to 19.9 times, and the polarization extinction ratio was enhanced by 2.7 to 22.3 times. The highest polarization extinction ratio reached 3.04 × 105 at 0.5 THz. The results are based on the numerical simulations of the light and the thermal fields.

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Tonouchi, M., M. Tani, Z. Wang, K. Sakai, M. Hangyo, N. Wada, and Y. Murakami. "Enhanced THz radiation from YBCO thin film bow-tie antennas with hyper-hemispherical MgO lens." IEEE Transactions on Appiled Superconductivity 7, no. 2 (June 1997): 2913–16. http://dx.doi.org/10.1109/77.621910.

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Wan Jalal, Wan Nasarudin, Huda Abdullah, and Mohd Syafiq Zulfakar. "Effect of Zn Site for Ca Substitution on Optical and Microwave Dielectric Properties of ZnAl2O4Thin Films by Sol Gel Method." Advances in Materials Science and Engineering 2014 (2014): 1–8. http://dx.doi.org/10.1155/2014/619024.

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CaxZn(1-x)Al2O4(x= 0.00, 0.05, 0.10, 0.15, 0.20, 0.25, and 0.30) thin films were prepared by a sol gel method. The XRD patterns displayed the characteristic peaks of (Ca/Zn)Al2O4with the standard pattern of face-centred cubic (fcc). The addition of Ca decreased the lattice constant from 14.6 nm to 23.2 nm. The optical bandgap of undoped thin film was found to be at 3.84 eV while for doped Ca was observed at 3.50 to 3.73 eV. The substitution of Zn2+by Ca2+in ZnAl2O4thin films was found to increase the crystallite size, grain size, and surface morphology which evidently affect the density and dielectric constant. TheCaxZn1-xAl2O4thin films were characterized at 20 to 1 MHZ frequency to determine the dielectric constantεrand unloaded quality factorQuusing LCR spectrometer. It can be observed that specimen using Ca0.25Zn0.75Al2O4possessesεr~10.41andQu~5770which is suggested as a candidate material for millimetre-wave applications. Therefore, this ceramic is suggested as a candidate material for GPS patch antennas.

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Li, Peixuan, Yuxiang Wang, Jiahao He, and Xiaojun Huang. "Broadband Ultra-Thin High-Efficiency Linear Polarizer Based on Metasurfaces." Electronics 11, no. 16 (August 19, 2022): 2599. http://dx.doi.org/10.3390/electronics11162599.

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In this paper, an ultra-wideband (UWB) polarizer with high performance based on the metasurface is designed and demonstrated, which is composed of a dielectric substrate with a double-gap circular pattern and metal film. Multiple strong resonance points enable the design to achieve the conversion from incident linearly polarized waves to cross-polarized waves at 6.49–11.64 GHz, with a fractional bandwidth of 56.8% and a corresponding polarization conversion rate (PCR) of 90%. The PCR remains above 90% at 6.49–11.52 GHz when the electromagnetic wave is obliquely incident between 0° and 30°. Furthermore, the surface current distribution of the polarizer is discussed to explain the physical mechanism. The sample is fabricated for microwave validation. Compared with previous reports, the proposed polarizer has a larger bandwidth and higher efficiency and is expected to be used in microwave communications, antennas, radar cross section reduction, and other fields.

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Chishti, Abdul Rehman, Abdul Aziz, Muhammad Ali Qureshi, Muhammad Nawaz Abbasi, Abdullah M. Algarni, Azzedine Zerguine, Niamat Hussain, and Rifaqat Hussain. "Optically Transparent Antennas: A Review of the State-of-the-Art, Innovative Solutions and Future Trends." Applied Sciences 13, no. 1 (December 24, 2022): 210. http://dx.doi.org/10.3390/app13010210.

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The requirement of mounting several access points and base stations is increasing tremendously due to recent advancements and the need for high-data-rate communication services of 5G and 6G wireless communication systems. In the near future, the enormous number of these access points might cause a mess. In such cases, an optically transparent antenna (OTA) is the best option for making the environment more appealing and pleasant. OTAs provide the possible solution as these maintain the device aesthetics to achieve transparency as well as fulfill the basic coverage and bandwidth requirements. Various attempts have been made to design OTAs to provide coverage for wireless communication, particularly for the dead zones. These antennas can be installed on building windows, car windscreens, towers, trees, and smart windows, which enables network access for vehicles and people passing by those locations. Several transparent materials and techniques are used for transparent antenna design. Thin-film and mesh-grid techniques are very popular to transform metallic parts of the antenna into a transparent material. In this article, a comprehensive review of both the techniques used for the design of OTAs is presented. The performance comparison of OTAs on the basis of bandwidth, gain, transparency, transmittance, and efficiency is also presented. An OTA is the best choice in these situations to improve the aesthetics and comfort of the surroundings with high antenna performance.

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Cho, Sunghun, Jun Seop Lee, and Hyeonseo Joo. "Recent Developments of the Solution-Processable and Highly Conductive Polyaniline Composites for Optical and Electrochemical Applications." Polymers 11, no. 12 (November 29, 2019): 1965. http://dx.doi.org/10.3390/polym11121965.

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Solution-processable conducting polymers (CPs) are an effective means for producing thin-film electrodes with tunable thickness, and excellent electrical, electrochemical, and optical properties. Especially, solution-processable polyaniline (PANI) composites have drawn a great deal of interest due to of their ease of film-forming, high conductivity up to 103 S/cm, excellent redox behaviors, processability, and scalability. In this review, basic principles, fabrication methods, and applications of solution-processable PANI composites will be discussed. In addition, recent researches on the PANI-based electrodes for solar cells (SCs), electrochromic (EC) windows, thermoelectric (TE) materials, supercapacitors, sensors, antennas, electromagnetic interference (EMI) shielding, organic field-effect transistors (OFETs), and anti-corrosion coatings will be discussed. The presented examples in this review will offer new insights in the design and fabrication of high-performance electrodes from the PANI composite solutions for the development of thin-film electrodes for state-of-art applications.

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Romanofsky, Robert R. "Advances in Scanning Reflectarray Antennas Based on Ferroelectric Thin-Film Phase Shifters for Deep-Space Communications." Proceedings of the IEEE 95, no. 10 (October 2007): 1968–75. http://dx.doi.org/10.1109/jproc.2007.905065.

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Chen, Chia-Yuan, Nuttapol Pootrakulchote, Shi-Jhang Wu, Mingkui Wang, Jheng-Ying Li, Jia-Hung Tsai, Chun-Guey Wu, Shaik M. Zakeeruddin, and Michael Grätzel. "New Ruthenium Sensitizer with Carbazole Antennas for Efficient and Stable Thin-Film Dye-Sensitized Solar Cells." Journal of Physical Chemistry C 113, no. 48 (November 2, 2009): 20752–57. http://dx.doi.org/10.1021/jp9089084.

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36

Wang, Zhongbao, Yanli Ma, Ming Li, Liangfei Wu, Tiantian Guo, Yuejun Zheng, Qiang Chen, and Yunqi Fu. "A Thermal-Switchable Metamaterial Absorber Based on the Phase-Change Material of Vanadium Dioxide." Nanomaterials 12, no. 17 (August 30, 2022): 3000. http://dx.doi.org/10.3390/nano12173000.

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This article presents a thermal-switchable metamaterial absorber (TSMA) based on the phase-change material of vanadium dioxide (VO2). VO2 thin film was deposited on sapphire substrate by magnetron sputtering followed by vacuum annealing treatment. Then, the prepared VO2 film was sliced into tiny chips for thermal-switchable elements. The surface structure of TSMA was realized by loading four VO2 chips into a square metallic loop. The absorption frequency of TSMA was located at 7.3 GHz at room temperature and switched to 6.8 GHz when the temperature was heated above the critical phase transition temperature of VO2. A VO2-based TSMA prototype was fabricated and measured to verify this design. The design is expected to be used in metasurface antennas, sensors, detectors, etc.

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Chen, Peiyu, Mostafa Hosseini, and Aydin Babakhani. "An Integrated Germanium-Based THz Impulse Radiator with an Optical Waveguide Coupled Photoconductive Switch in Silicon." Micromachines 10, no. 6 (May 31, 2019): 367. http://dx.doi.org/10.3390/mi10060367.

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This paper presents an integrated germanium (Ge)-based THz impulse radiator with an optical waveguide coupled photoconductive switch in a low-cost silicon-on-insulator (SOI) process. This process provides a Ge thin film, which is used as photoconductive material. To generate short THz impulses, N++ implant is added to the Ge thin film to reduce its photo-carrier lifetime to sub-picosecond for faster transient response. A bow-tie antenna is designed and connected to the photoconductive switch for radiation. To improve radiation efficiency, a silicon lens is attached to the substrate-side of the chip. This design features an optical-waveguide-enabled “horizontal” coupling mechanism between the optical excitation signal and the photoconductive switch. The THz emitter prototype works with 1550 nm femtosecond lasers. The radiated THz impulses achieve a full-width at half maximum (FWHM) of 1.14 ps and a bandwidth of 1.5 THz. The average radiated power is 0.337 μ W. Compared with conventional THz photoconductive antennas (PCAs), this design exhibits several advantages: First, it uses silicon-based technology, which reduces the fabrication cost; second, the excitation wavelength is 1550 nm, at which various low-cost laser sources operate; and third, in this design, the monolithic excitation mechanism between the excitation laser and the photoconductive switch enables on-chip programmable control of excitation signals for THz beam-steering.

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Kaidashev, E. M., A. M. Lerer, E. V. Golovacheva, V. E. Kaydashev, N. V. Lyanguzov, and E. A. Tsvetyanskii. "Experimental and Theoretical Study of Optical Antennas Formed from ZnO Nanorods Coated with a Thin Silver Film." Journal of Communications Technology and Electronics 62, no. 12 (December 2017): 1328–35. http://dx.doi.org/10.1134/s1064226917110055.

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Lazcano-Ortiz, Zorayda, Cesar L. Ordóñez-Romero, Jorge Luis Domínguez-Juárez, Guillermo Monsivais, Rafael Quintero-Torres, Daniel Matatagui, José Roberto Fragoso-Mora, Naser Qureshi, and Oleg Kolokoltsev. "Magnonic Crystal with Strips of Magnetic Nanoparticles: Modeling and Experimental Realization via a Dip-Coating Technique." Magnetochemistry 7, no. 12 (November 26, 2021): 155. http://dx.doi.org/10.3390/magnetochemistry7120155.

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In this article, we describe a magnonic crystal formed by magnetite nanoparticles. The periodic strip-like structure of the nanoparticles was fabricated on the surface of thin yttrium iron garnet single-crystal film grown on a gallium–gadolinium garnet substrate via dip-coating techniques. It was shown that such periodic structure induces the formation of the bandgaps in the transmission spectra of magnetostatic surface spin-waves (MSSW). The structure was simulated by the transfer matrix method. Spin-wave detection has been carried out by using a pair of microwave antennas and a vector network analyzer.

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Abu, Maisarah, Nur Asyrani Mohd Asari, Khairul Nabilah Zainul Ariffin, Nurul Najwa Md Yusof, and Eryana Eiyda Hussin. "Bendable Hexagonal Resonator Designs for Chipless Tag." Applied Mechanics and Materials 850 (August 2016): 82–87. http://dx.doi.org/10.4028/www.scientific.net/amm.850.82.

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This paper presented a new design of bendable hexagonal resonator for chipless RFID tag. A linearly polarized plane wave and Radar Cross Section (RCS) probes were used in simulation set-up. The optimized resonator was fabricated on a thin fast-film substrate with dielectric constant, εr=2.7 and substrate thickness, t = 0.13 mm. The fabricated resonator consisted of 3 hexagonal slots which represented three bit 1s. The measurement was performed to validate the designed resonator. It was measured using two transmitting and receiving horn antennas along with the network analyzer. The measured magnitudes were-24.292 dB, -28.854 dB and-32.234 dB.

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Fumeaux, C., W. Herrmann, H. Rothuizen, P. De Natale, and F. K. Kneubühl. "Mixing of 30 THz laser radiation with nanometer thin-film Ni-NiO-Ni diodes and integrated bow-tie antennas." Applied Physics B 63, no. 2 (August 1996): 135–40. http://dx.doi.org/10.1007/bf01095263.

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Crippa, Paolo, Giorgio Biagetti, Lorenzo Minelli, Claudio Turchetti, Martino Aldrigo, Mircea Dragoman, Davide Mencarelli, and Luca Pierantoni. "Next-Generation Hybrid RF Front-End with MoS2-FET Supply Management Circuit, CNT-FET Amplifiers, and Graphene Thin-Film Antennas." Electronics 11, no. 22 (November 12, 2022): 3708. http://dx.doi.org/10.3390/electronics11223708.

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One-dimensional (1D) and two-dimensional (2D) materials represent the emerging technologies for transistor electronics in view of their attractive electrical (high power gain, high cut-off frequency, low power dissipation) and mechanical properties. This work investigates the integration of carbon-nanotube-based field-effect transistors (CNT-FETs) and molybdenum disulphide (MoS2)-based FETs with standard CMOS technology for designing a simple analog system integrating a power switching circuit for the supply management of a 10 GHz transmitting/receiving (T/R) module that embeds a low-noise amplifier (LNA) and a high-power amplifier (HPA), both of which loaded by nanocrystalline graphene (NCG)-based patch antennas. Verilog-A models, tuned to the technology that will be used to manufacture the FETs, were implemented to perform electrical simulations of the MoS2 and CNT devices using a commercial integrated circuit software simulator. The obtained simulation results prove the potential of hybrid CNT-MoS2-FET circuits as building blocks for next-generation integrated circuits for radio frequency (RF) applications, such as radars or IoT systems.

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Romanofsky, R. R., J. T. Bernhard, F. W. van Keuls, F. A. Miranda, G. Washington, and C. Canedy. "K-band phased array antennas based on Ba/sub 0.60/Sr/sub 0.40/TiO/sub 3/ thin-film phase shifters." IEEE Transactions on Microwave Theory and Techniques 48, no. 12 (2000): 2504–10. http://dx.doi.org/10.1109/22.899005.

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Vera-Reveles, Gustavo, José Vulfrano González-Fernández, Juan Francisco Castillo-León, Francisco Javier González, Ramón Díaz de León-Zapata, Ariel Benjamín de la Rosa-Zapata, Norma Orocio-Castro, and Jorge Simón. "Tuning Bolometric Parameters of Sierpinski Fractal Antenna-Coupled Uncracked/Cracked SWCNT Films by Thermoelectric Characterization at UHF Frequencies." Electronics 11, no. 11 (May 24, 2022): 1665. http://dx.doi.org/10.3390/electronics11111665.

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In this work, the bolometric parameters of Sierpinski fractal antenna-coupled SWCNT semi-metallic films are obtained by thermoelectric characterization, this in order to find out the performance as bolometer. The method was based on an experimental setup considering a line-of-sight wireless link between two identical planar fractal antennas, infrared thermography, and electrical resistance measurements. The experimental setup considered the antennas resonant frequencies. Both the transmitting and receiving antenna were third-iteration Sierpinski fractal dipoles designed to work at UHF frequencies. Films made either of cracked or uncracked SWCNT films were each separately coupled to the receiving fractal antenna. Measurements showed that the receiving antenna that was impinged with radiation at UHF frequencies coming from the transmitting antenna, experienced as it was expected an induction of electric current, the induced current flowed through the film producing a temperature change, which in turn caused changes in the radiated heat of the film, as well as changes in the electrical resistance known as Temperature Coefficient of Resistance TCR. The maximum value of TCR for uncracked SWCNT films was −3.6%K−1, higher than the one observed for cracked SWCNT films which exhibited a maximum value of −1.46%K−1. Measurements for conversion of incident radiation to electrical signals known as the Voltage Responsivity ℜv, exhibited values of 9.4 mV/W and 1.4 mV/W for uncracked SWCNT films and cracked SWCNT films, respectively.

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Zheng, Bin, Xiangyang Li, Xin Rao, and Na Li. "Multi-Beam Conformal Array Antenna Based on Highly Conductive Graphene Films for 5G Micro Base Station Applications." Sensors 22, no. 24 (December 10, 2022): 9681. http://dx.doi.org/10.3390/s22249681.

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Recently, micro base station antennas have begun to play a more important role in 5G wireless communication, with the rapid development of modern smart medical care, the Internet of things, and portable electronic devices. Meanwhile, in response to the global commitment to long-term carbon neutrality, graphene film has received significant attention in the field of antennas due to its low carbon environmental impact and high electrical conductivity properties. In this work, a conformal array antenna based on highly conductive graphene films (CGF) is proposed for 5G millimeter-wave (MMW) applications. The proposed antenna consists of three antenna arrays, with eight patch elements in each array, operating at 24 GHz, with linear polarization. Each antenna array’s current amplitude distribution coefficient is constructed by synthesizing a series-feeding linear array using the Chebyshev method. The measurement results demonstrated that the proposed CGF antenna exhibits a peak realized gain higher than 8 dBi in the bandwidth of 23.0–24.7 GHz. The proposed antenna achieves three independent beams from bore-sight to ±37° in conformal installations, with a cylinder radius of 30 mm, showing excellent beam-pointing performance. These characteristics indicate that the CGF can be used for the design of MMW micro base station antennas, fulfilling the requirements of the conformal carrier platform for a lightweight and compact antenna.

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Tani, Masahiko, Masayoshi Tonouchi, Zhen Wang, Kiyomi Sakai, Masanori Hangyo, Seiji Tomozawa, and Yoshishige Murakami. "Enhanced Sub-Picosecond Electromagnetic Radiation from $\bf YBa_{2}Cu_{3}O_{7-{\ninmbi \delta}}$ Thin-Film Bow-Tie Antennas Excited with Femtoseconds Laser Pulses." Japanese Journal of Applied Physics 35, Part 2, No. 9B (September 15, 1996): L1184—L1187. http://dx.doi.org/10.1143/jjap.35.l1184.

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Lin, Yu-Ming, Hung-Wei Wu, and Shoou-Jinn Chang. "Design of LTE/Sub-6 GHz Dual-Band Transparent Antenna Using Frame-Structured Metal Mesh Conductive Film." Nanomaterials 13, no. 2 (January 4, 2023): 221. http://dx.doi.org/10.3390/nano13020221.

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This paper proposes a dual-band transparent antenna using frame-structured metal mesh conductive film (MMCF). The frame-structured metal mesh conductive film is based on the conductive-coated thin film and forms a narrow strip surrounding the edge of the antenna. The frame-structured metal mesh conductive film can resist considerable current leakage on the edge of the conductive strip to improve the antenna’s efficiency by 51% at 2.1 GHz and 53% at 3.6 GHz. As a result, the transparent dual-band antenna has an operating bandwidth of 1.9–2.4 GHz and 3.2–4.1 GHz with a high transparency of 80%, which make it valuable to the applications of biomedical electronic components, wearable devices, and automobile vehicles.

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Abdullah, Huda, Wan Nasarudin Wan Jalal, Mohd Syafiq Zulfakar, Mohammad Tariqul Islam, Badariah Bais, Sahbudin Shaari, and Sarada Idris. "Fabrication and Characterization of TiO₂-Doped ZnAl₂O₄ Nanocrystals via Sol-Gel Method for GPS Antenna." Materials Science Forum 846 (March 2016): 331–44. http://dx.doi.org/10.4028/www.scientific.net/msf.846.331.

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The Zn(1-x)TixAl2O4 (x = 0.00, 0.05, 0.15 & 0.25) nanocrystals thin films were prepared by sol-gel method. The properties of Zn(1-x)TixAl2O4 were investigated by X-ray diffraction (XRD), Atomic Force Microscope (AFM), Fourier transform infrared spectra (FTIR) and (UV-Vis). By indexing the XRD patterns, we identified three structural types which is ZnAl2O4, anatase and rutile. The addition of TiO2 increased the crystallite size from 14.65 to 25.25 nm. The direct band gap was found to be around 3.35 to 3.84 eV. The addition of TiO2 increased the crystallite size, surface roughness, and lattice parameters of the resultant films, evidently affecting their density and dielectric constant (). The thin films were characterized in the certain frequency to determine the using LCR spectrometer. The and density value of the Zn(1-x)TixAl2O4 films increase linearly from 8.56 to 13.48 and 4.60 to 4.70 g/cm3 with the increasing of x value, respectively. Based on the material analysis and microwave antenna theory, GPS patch antennas were fabricated using the Zn(1-x)TixAl2O4 material. The fabricated GPS antenna with the highest (13.48) material exhibits the smallest size of antenna which is 7.45 cm2. The performances and the operating frequencies were measured using a PNA series network analyzer. The result showed that all patch antennas operate at frequency of 1.570 GHz. The GPS patch antenna fabricated from Zn0.25Ti0.75Al2O4 showed an excellent combination of return loss (-29.6 dB), smallest size (7.85 cm2), and wide bandwidth (195 MHz). All fabricated antennas are meets the requirements of GPS applications.

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de Menezes, Fernando Lima, Davino Machado Andrade Neto, Maria do Livramento Linhares Rodrigues, Helder Levi Silva Lima, Denis Valony Martins Paiva, Marcelo Antônio Santos da Silva, Lillian Maria Uchôa Dutra Fechine, et al. "From Magneto-Dielectric Biocomposite Films to Microstrip Antenna Devices." Journal of Composites Science 4, no. 4 (September 24, 2020): 144. http://dx.doi.org/10.3390/jcs4040144.

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Magneto-dielectric composites are interesting advanced materials principally due to their potential applications in electronic fields, such as in microstrip antennas substrates. In this work, we developed superparamagnetic polymer-based films using the biopolymeric matrices chitosan (Ch), cellulose (BC) and collagen (Col). For this proposal, we synthesized superparamagnetic iron oxide nanoparticles (SPIONs) functionalized with polyethyleneimine with a cheap method using sonochemistry. Further, the SPIONs were dispersed into polymer matrices and the composites were evaluated regarding morphology, thermal, dielectric and magnetic properties and their application as microstrip antennas substrates. Microscopically, all tested films presented a uniform dispersion profile, principally due to polyethyleneimine coating. Under an operating frequency (fo) of 4.45 GHz, Ch, BC and Col-based SPION substrates showed moderate dielectric constant (ε′) values in the range of 5.2–8.3, 6.7–8.4 and 5.9–9.1, respectively. Furthermore, the prepared films showed no hysteresis loop, thereby providing evidence of superparamagnetism. The microstrip antennas showed considerable bandwidths (3.37–6.34%) and a return loss lower than −10 dB. Besides, the fo were modulated according to the addition of SPIONs, varying in the range of 4.69–5.55, 4.63–5.18 and 4.93–5.44 GHz, for Ch, BC and Col-based substrates, respectively. Moreover, considering best modulation of ε′ and fo, the Ch-based SPION film showed the most suitable profile as a microstrip antenna substrate.

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Chen, Hongzhi, Ning Xi, King Wai Chiu Lai, Liangliang Chen, Carmen Kar Man Fung, and Jianyong Lou. "Plasmonic-Resonant Bowtie Antenna for Carbon Nanotube Photodetectors." International Journal of Optics 2012 (2012): 1–9. http://dx.doi.org/10.1155/2012/318104.

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The design of bowtie antennas for carbon nanotube (CNT) photodetectors has been investigated. CNT photodetectors have shown outstanding performance by using CNT as sensing element. However, detection wavelength is much larger than the diameter of the CNT, resulting in small fill factor. Bowtie antenna can confine light into a subwavelength volume based on plasmonic resonance, thus integrating a bowtie antenna to CNT photodetectors can highly improve photoresponse of the detectors. The electric field enhancement of bowtie antennas was calculated using the device geometry by considering fabrication difficulties and photodetector structure. It is shown that the electric field intensity enhancement increased exponentially with distance reduction between the CNT photodetector to the antenna. A redshift of the peak resonance wavelength is predicted due to the increase of tip angles of the bowtie antennas. Experimental results showed that photocurrent enhancement agreed well with theoretical calculations. Bowtie antennas may find wide applications in nanoscale photonic sensors.

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Journal articles on the topic 'Thin film antennas'

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