The Experts below are selected from a list of 51348 Experts worldwide ranked by ideXlab platform
Kin-lu Wong - One of the best experts on this subject based on the ideXlab platform.
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Very-Low-Profile Dual-Wideband Tablet Computer Antenna for LTE Operation
2020Co-Authors: Meng-ting Chen, Kin-lu WongAbstract:Abstract -A very-low-profile (8 mm in height), small-size (8 × 3 × 40 mm 3 ), and dual-wideband Loop antenna suitable for applications in the LTE tablet computer is presented. Dualwideband operation is achieved using a wideband feed structure formed by a coupling feed, a high-pass matching circuit, and a tuning inductor. The coupling feed leads to successful excitation of a quarter-wavelength Loop Mode in the desired lower band. The high-pass matching circuit widens the low-band bandwidth to cover the 698~960 MHz band. The tuning inductor can adjust the frequency ratio of the first two higher-order Loop Modes to form a wide higher band to cover the 1710~2690 MHz band. Details of the proposed antenna are presented. Index Terms -Mobile antennas, tablet computer antennas, LTE antennas, very-low-profile antennas, Loop antennas
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passive reconfigurable triple wideband antenna for lte tablet computer
IEEE Transactions on Antennas and Propagation, 2015Co-Authors: Kin-lu Wong, Zih-guang LiaoAbstract:A passive reconfigurable triple-wideband tablet computer antenna for the LTE operation in the low band of $698\sim 960~{\rm MHz}$ , middle band of $1710\sim 2690~{\rm MHz}$ , and high band of $3400\sim 3800~{\rm MHz}$ is presented. The antenna mainly acts like an inverted-F antenna (IFA) at frequencies in the LTE low and middle bands and like a Loop antenna at frequencies in the LTE high band. The reconfigurable IFA/Loop antenna is achieved without active switch circuits and occupies a small volume of $10 \times 35 \times 3~{\rm mm}^{3}$ . The antenna is obtained by first configuring the radiating arm of an IFA to be folded and coupled to the device ground plane through a distributed capacitor. Then, the IFA's shorting and feeding strips are respectively loaded with an inductor and a capacitor. This leads to good excitation of a resonant Mode generated in the LTE low band with the radiating arm length of the IFA only about 0.16 wavelength at 800 MHz. By further aided using a high-pass matching circuit integrated within the antenna, a wide low band is obtained for the antenna. The IFA's first two higher-order Modes can also be excited in the middle band. Owing to the distributed capacitor between the IFA's radiating arm and the device ground plane, the two higher-order Modes can lead to a wide middle band for the antenna. At frequencies in the LTE high band, the antenna mainly acts like a Loop antenna operated at its one-wavelength Loop Mode, which contributes to a wide high band for the antenna. Triple-wideband operation covering the LTE operation is hence obtained. Details of the proposed antenna are described, and experimental results are presented. Working principle of the antenna acting like an IFA and a Loop antenna at different frequencies is discussed.
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very low profile dual wideband Loop antenna for lte tablet computer
Microwave and Optical Technology Letters, 2015Co-Authors: Kin-lu Wong, Meng-ting ChenAbstract:A very-low-profile (8 mm in height), small-size (8 × 3 × 40 mm3), and dual-wideband Loop antenna suitable for applications in the LTE tablet device such as a tablet computer is presented. Dual-wideband operation of the proposed Loop antenna is achieved using a wideband feed structure formed by a coupling feed, a high-pass matching circuit, and a tuning inductor. The coupling feed leads to successful excitation of a quarter-wavelength Loop Mode in the desired lower band. The high-pass matching circuit causes an additional resonance occurred near the excited quarter-wavelength Loop Mode to widen the low-band bandwidth to cover the 698–960 MHz band. The tuning inductor can adjust the frequency ratio of the first two higher-order Loop Modes to form a wide higher band to cover the 1710–2690 MHz band. Dual-wideband operation of the proposed Loop antenna for the LTE operation is hence obtained. Details of the proposed Loop antenna are addressed. Working principle of the antenna, especially the function of the wideband feed structure thereof, is described. Experimental results of the fabricated prototype are also presented. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:141–146, 2015
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internal wwan lte handset antenna integrated with usb connector
Microwave and Optical Technology Letters, 2012Co-Authors: Kin-lu Wong, Yuwei ChangAbstract:A new internal eight-band wireless wide area network (WWAN)/long-term evolution (LTE) handset antenna comprising a small antenna ground and two coupled-fed 0.25-wavelength Loop antennas disposed on two sides of the antenna ground is presented.In one Loop antenna, a chip inductor is embedded to result in dual-resonance excitation of its 0.25-wavelength Loop Mode and also to adjust the antenna's loading effects on the excited resonant Modes at higher frequencies contributed by the other Loop antenna. The chip inductor loading greatly helps the proposed antenna in achieving two wide operating bands for the desired WWAN/LTE operation in the 704–960 and 1710–2690 MHz bands. The proposed antenna is especially suitable to be mounted on top of a protruded ground extended from the main ground of the handset to accommodate a universal series bus connector, which serves as a data port of the handset. Details of the proposed antenna are described. Radiation characteristics and specific absorption rate of the antenna are also presented and discussed. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1154–1159, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26788
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internal coupled fed Loop antenna integrated with notched ground plane for wireless wide area network operation in the mobile handset
Microwave and Optical Technology Letters, 2012Co-Authors: Kin-lu WongAbstract:An internal wireless wide area network (824–960/1710–2170 MHz) antenna suitable to be disposed at a notched region (size 10 × 40 mm2) of the system ground plane of the handset to achieve compact integration therein is presented.The notched system ground plane, compared to the traditional rectangular system ground plane at which the internal antenna is generally disposed at the entire top or bottom edge of the ground plane, can lead to more compact layout design of the internal antenna and associated electronic elements in the handset. The proposed antenna has a simple structure occupying a small volume of 10 × 40 × 5 mm3 and comprising a monopole feed and a coupled strip. The latter is coupled-fed by the monopole feed to provide a 0.25-wavelength Loop path, which generates a 0.25-wavelength Loop Mode at about 850 MHz and a higher-order Loop Mode at about 1.7 GHz. The monopole feed also contributes a 0.25-wavelength Mode at about 2.1 GHz to combine with the higher-order Loop Mode to form the antenna's upper band. The bandwidth enhancement of the 0.25-wavelength Loop Mode is obtained by adding an external bandstop circuit, which makes the desired antenna's lower band achieved. The antenna also meets the specific absorption rate and hearing-aid compatibility requirements for practical applications. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:553–555, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26620
Shaoqiu Xiao - One of the best experts on this subject based on the ideXlab platform.
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miniaturized cylindrical open ended siw cavity antenna and its dual band applications
IEEE Transactions on Antennas and Propagation, 2021Co-Authors: Chunmei Liu, Shaoqiu XiaoAbstract:A cylindrical open-ended substrate-integrated waveguide (SIW) cavity is studied and analyzed in this work. Two orthogonally oriented gaps are used to shrink the dimension of the cylindrical open-ended SIW cavity. Then, the miniaturized cylindrical open-ended SIW cavity is used to construct dual-band antennas. One dual-band antenna is realized by a composite structure that supports two independent Modes: they are the half-circular Loop Mode for the lower band and the half quasi TE11(1/2) Mode for the upper band. The other dual-band antenna is an aperture-shared structure: the lower band is related to the miniaturized cylindrical open-ended SIW cavity which works at the quasi TE11(1/2) Mode; the upper band is characterized by suspending a concentric slot-loaded circular patch which works at the TM11 patch Mode over the empty space of the miniaturized cylindrical open-ended SIW cavity. All Modes involved in the two dual-band antennas, the half-circular Loop Mode, the half quasi TE11(1/2) Mode, the quasi TE11(1/2) Mode, and TM11 Mode, are featured by broadside radiation. The structures of the two dual-band antennas are easy to fabricate by using conventional printed circuit board (PCB) techniques and can be integrated with other planar circuits. Compared to other open-ended cavity antennas, the proposed cylindrical counterpart shows a more compact size and lower profile.
Zih-guang Liao - One of the best experts on this subject based on the ideXlab platform.
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passive reconfigurable triple wideband antenna for lte tablet computer
IEEE Transactions on Antennas and Propagation, 2015Co-Authors: Kin-lu Wong, Zih-guang LiaoAbstract:A passive reconfigurable triple-wideband tablet computer antenna for the LTE operation in the low band of $698\sim 960~{\rm MHz}$ , middle band of $1710\sim 2690~{\rm MHz}$ , and high band of $3400\sim 3800~{\rm MHz}$ is presented. The antenna mainly acts like an inverted-F antenna (IFA) at frequencies in the LTE low and middle bands and like a Loop antenna at frequencies in the LTE high band. The reconfigurable IFA/Loop antenna is achieved without active switch circuits and occupies a small volume of $10 \times 35 \times 3~{\rm mm}^{3}$ . The antenna is obtained by first configuring the radiating arm of an IFA to be folded and coupled to the device ground plane through a distributed capacitor. Then, the IFA's shorting and feeding strips are respectively loaded with an inductor and a capacitor. This leads to good excitation of a resonant Mode generated in the LTE low band with the radiating arm length of the IFA only about 0.16 wavelength at 800 MHz. By further aided using a high-pass matching circuit integrated within the antenna, a wide low band is obtained for the antenna. The IFA's first two higher-order Modes can also be excited in the middle band. Owing to the distributed capacitor between the IFA's radiating arm and the device ground plane, the two higher-order Modes can lead to a wide middle band for the antenna. At frequencies in the LTE high band, the antenna mainly acts like a Loop antenna operated at its one-wavelength Loop Mode, which contributes to a wide high band for the antenna. Triple-wideband operation covering the LTE operation is hence obtained. Details of the proposed antenna are described, and experimental results are presented. Working principle of the antenna acting like an IFA and a Loop antenna at different frequencies is discussed.
Chunmei Liu - One of the best experts on this subject based on the ideXlab platform.
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aperture shared x ka band cylindrical open ended siw cavity antenna
International Symposium on Antenna Technology and Applied Electromagnetics, 2021Co-Authors: Chunmei LiuAbstract:An aperture-shared X/Ka-band cylindrical open-ended substrate integrated waveguide (SIW) cavity antenna is studied and presented. In this case, the TE 11½ Mode of the cylindrical open-ended SIW cavity contributes to the Ka-band from 28.8 GHz to 30.3 GHz. A circular ring detached from the cylindrical open-ended SIW cavity contributes to the X-band. Fundamental Loop Mode of the circular ring is involved, resonating at f=8.83 GHz. Large frequency ratio of 3.4 is achieved. Both the TE 11½ Mode of the cylindrical open-ended SIW cavity and the fundamental Loop Mode of the circular ring lead to a broadside radiation. The proposed antenna has a height of 0.13 λ g1 and a diameter of 0. 39 λ g1 (λ g1 denotes the waveguide wavelength corresponding to the resonant frequency of X-band). The structure is easy to realize by using PCB technology and can be integrated with other planar circuits. Multi-layer technology is essential for the presented work.
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miniaturized cylindrical open ended siw cavity antenna and its dual band applications
IEEE Transactions on Antennas and Propagation, 2021Co-Authors: Chunmei Liu, Shaoqiu XiaoAbstract:A cylindrical open-ended substrate-integrated waveguide (SIW) cavity is studied and analyzed in this work. Two orthogonally oriented gaps are used to shrink the dimension of the cylindrical open-ended SIW cavity. Then, the miniaturized cylindrical open-ended SIW cavity is used to construct dual-band antennas. One dual-band antenna is realized by a composite structure that supports two independent Modes: they are the half-circular Loop Mode for the lower band and the half quasi TE11(1/2) Mode for the upper band. The other dual-band antenna is an aperture-shared structure: the lower band is related to the miniaturized cylindrical open-ended SIW cavity which works at the quasi TE11(1/2) Mode; the upper band is characterized by suspending a concentric slot-loaded circular patch which works at the TM11 patch Mode over the empty space of the miniaturized cylindrical open-ended SIW cavity. All Modes involved in the two dual-band antennas, the half-circular Loop Mode, the half quasi TE11(1/2) Mode, the quasi TE11(1/2) Mode, and TM11 Mode, are featured by broadside radiation. The structures of the two dual-band antennas are easy to fabricate by using conventional printed circuit board (PCB) techniques and can be integrated with other planar circuits. Compared to other open-ended cavity antennas, the proposed cylindrical counterpart shows a more compact size and lower profile.
Richard A Anthes - One of the best experts on this subject based on the ideXlab platform.
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monitoring the atmospheric boundary layer by gps radio occultation signals recorded in the open Loop Mode
Geophysical Research Letters, 2006Co-Authors: C Rocken, William Schreiner, Douglas Hunt, Richard A AnthesAbstract:[1] A new type of radio occultation (RO) data, recorded in open-Loop (OL) Mode from the SAC-C satellite, has been tested for monitoring refractivity in the Atmospheric Boundary Layer (ABL). Previously available RO signals, recorded in phase-locked Loop Mode were often unusable for sensing the lower troposphere (LT) or resulted in significant inversion errors, especially in the tropics. The OL RO signals allow sensing of the LT and accurate monitoring of the ABL and, especially, its depth. Comparison of RO-inverted refractivity profiles to ECMWF analysis and available radiosondes generally shows good agreement in the depth of the ABL. However, in a number of cases, ECMWF fails to reproduce the top of ABL. Future OL RO signals will provide information about the ABL depth which is an important parameter for weather prediction and climate monitoring.
