Browsing by Author "Chen, Fu-Chiarng"

Now showing 1 - 20 of 38

4-Port Quadri-Polarization Diversity Antenna with a Novel Feeding Network
(2012)
Chi, Yu-Jen
;
Chen, Fu-Chiarng
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
A novel planar antenna with quadri-polarization diversity, including a pair of orthogonal linear polarizations and a pair of orthogonal circular polarizations is presented in this paper. The antenna comprises two square patch resonators and a feeding network with 4 input ports. Antenna polarization diversity can be achieved by selecting different inputs, which can generates right-handed circular polarization, left-handed circular polarization, horizontal linear polarization and vertical linear polarization. The proposed design does not need PIN diodes and DC biasing circuits, which makes it suitable to be used in higher frequency applications where lump elements are difficult to be utilized. This novel antenna provides potential polarization diversity features for wireless local area networks and multiple-input multiple-output systems. Details of the antenna design are shown, and the measurement and simulation results are also provided to validate the proposed idea.
60-GHz Polarization-Adjustable Antenna Arrays
(2015-07-01)
Chi, Yu-Jen
;
Chen, Fu-Chiarng
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes 2 x 2 and 4 x 4 polarization-adjustable millimeter-wave antenna arrays. The antennas were designed to function at 60 GHz and are planar and vialess. The proposed antenna designs contain two input ports; if the input phases and magnitudes of the two input ports can be controlled, enabling the proposed antenna to generate six types of polarization: right-handed circular polarization, left-handed circular polarization, and linear polarization along the phi = 0 degrees, phi = 45 degrees, phi = 90 degrees, and phi = 135 degrees axes. The achieved antenna gain of the 2 x 2 polarization diversity array was approximately 12 dBi, whereas that of the 4 x 4 array was 16 dBi. Prototypes of both the 2 x 2 and 4 x 4 arrays were fabricated and tested. The operating mechanism and design steps are described in detail in this paper.
A compact dual-band dual-polarized patch antenna for 1800/5800 MHz cellular/WLAN systems
(2007-02-01)
Lai, Don-Yen
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
In this paper, we present a compact dual-band dual-polarized aperture-coupled patch antenna for 1800/5800 MHz DCS/WLAN applications. With properly designed feeding network and patch dimensions, the antenna can provide a pair of orthogonal linear polarization states for dual bands operations. (c) 2006 Wiley Periodicals, Inc.
A Low-Profile Switchable Quadripolarization Diversity Aperture-Coupled Patch Antenna
(2009)
Wang, Shi-Yung
;
Lai, Don-Yen
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
In this letter, we present a low-profile switchable quadripolarization diversity aperture-coupled patch antenna. The proposed antenna can provide four polarization states by controlling the dc bias voltage of four p-i-n diodes in the feeding network. The experimental results validate the novel antenna provides polarization diversity features for wireless local area networks (WLANs) and multiple-input-multiple-output (MIMO) systems.
A modified PML conductivity profile for the ADI-FDTD method with split-field PML
(2007)
Hwang, Jiunn-Nan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
A new MIMO spatial correlation approximation of large angular spread
(2007)
Hsieh, Po-Chuan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
A New Spatial Correlation Formulation of Arbitrary AoA Scenarios
(2009)
Hsieh, Po-Chuan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
This letter presents a new approximate spatial correlation formulation of arbitrary angle-of-arrival (AoA) scenarios. The proposed approximation scheme can be applied to the parameterized three-dimensional (3-D) spatial correlation formulation taking antenna mutual coupling effect into consideration. Computation time can thus be significantly saved using the new spatial correlation formulation, which is beneficial for gauge of multiple-input -multiple-output (MIMO) antenna systems.
A New Ultra-Wideband Monocycle Pulse Generator Using Second-Order Transient Circuit
(2008)
Lin, Wun-Bi
;
Liu, Ying-Te
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
This paper presents a new ultra-wideband (UWB) monocycle pulse generator using two wideband bipolar junction transistors (BJTs) and a second-order transient circuit to generate monocycle pulse with good symmetry and low ringing. A voltage source can be applied to adjust the amplitude and duration of the pulse. This ultra-wideband pulse generator is fabricated with microstrip technology on FR4 printed circuit board. Our work shows that the pulse generator produces a monocycle pulse whose peak-to-peak amplitude ranges from 120 mV to 280 mV and duration from 780 ps to 600 ps respectively.
A New Ultra-Wideband Monocycle Pulse Generator Using Second-Order Transient Circuit
(2008)
Lin, Wun-Bi
;
Liu, Ying-Te
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
This paper presents a new ultra-wideband (UWB) monocycle pulse generator using two wideband bipolar junction transistors (BJTs) and a second-order transient circuit to generate monocycle pulse with good symmetry and low ringing. A voltage source can be applied to adjust the amplitude and duration of the pulse. This ultra-wideband pulse generator is fabricated with microstrip technology on FR4 printed circuit board. Our work shows that the pulse generator produces a monocycle pulse whose peak-to-peak amplitude ranges from 120 mV to 280 mV and duration from 780 ps to 600 ps respectively.
A New Ultra-Wideband Monocycle Pulse Generator Using Second-Order Transient Circuit
(2008-01-01)
Lin, Wun-Bi
;
Liu, Ying-Te
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
This paper presents a new ultra-wideband (UWB) monocycle pulse generator using two wideband bipolar junction transistors (BJTs) and a second-order transient circuit to generate monocycle pulse with good symmetry and low ringing. A voltage source can be applied to adjust the amplitude and duration of the pulse. This ultra-wideband pulse generator is fabricated with microstrip technology on FR4 printed circuit board. Our work shows that the pulse generator produces a monocycle pulse whose peak-to-peak amplitude ranges from 120 mV to 280 mV and duration from 780 ps to 600 ps respectively.
A Novel Planar Antenna for Wireless Body Area Network
(2012)
Chi, Yu-Jen
;
Chen, Fu-Chiarng
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
A novel planar antenna for wireless medical telemetry service is presented. It can be placed on the human body tissue with good antenna gain. This design is via-free and the half-wavelength patch mode of the antenna can be excited with a special feeding scheme. For different applications, the antenna can be used as a stand-alone antenna when it is fed by a coaxial cable, or to be integrated with a single chip sensor where the chip can be placed at the center of the antenna. Antenna parameters such as return loss and radiation patterns are also evaluated to validate the proposed design. Its characteristics of vialess, compact, and planar makes it a good candidate for wireless body area network applications.
A novel quadri-polarization-agile microstrip antenna with polarization synthesizing feeding network
(2016-03)
Chi, Yu-Jen
;
Chen, Fu-Chiarng
;
電子工程學系及電子研究所
;
Department of Electronics Engineering and Institute of Electronics
This paper proposes planar antennas with quadri-polarization diversity using a pair of orthogonal linear polarizations and a pair of orthogonal circular polarizations (CP). A novel feeding network with four input ports and four output ports is presented, allowing antenna polarization diversity by selecting different input ports, which can generate right-handed CP, left-handed CP, horizontal linear polarization, and vertical linear polarization. The first design uses two square patch resonators to synthesize the four polarizations; the second design comprises four circularly polarized patches to synthesize the four polarizations with an improved axial-ratio (the ratio of orthogonal components of an E-field) bandwidth. The proposed designs do not require for embedding PIN diodes and DC-biasing circuits, making them suitable for use in higher-frequency applications where using lump elements would be difficult. The novel antennas provide potential polarization diversity features which can be used for many applications. Details of the antenna design are shown, and the measurement and simulation results are also provided to validate the proposed concept.
A reconfigurable quadri-polarization diversity aperture-coupled patch antenna
(2007-03-01)
Wu, Yi-Fan
;
Wu, Chun-Hsien
;
Lai, Don-Yen
;
Chen, Fu-Chiarng
;
電信工程研究所
We present a novel reconfigurable quadri-polarization diversity aperture-coupled patch antenna which can provide four polarization states. By controlling the do bias voltage of the pin-diodes on the feeding network, we can reconfigure the proposed antenna to provide a pair of orthogonal linear polarizations and a pair of orthogonal circular polarizations. Numerical and experimental results validate our design. This novel antenna provides potential polarization diversity features for wireless local area networks and multiple-input multiple-output systems.
Analysis of stability and numerical dispersion relation of Mur's absorbing boundary condition in the ADI-FDTD method
(2007)
Hwang, Jiunn-Nan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
In this paper, the stability analysis of the Mur's first order absorbing boundary condition (ABC) in the alternating direction implicit finite-difference time-domain (ADI-FDTD) method is presented. To analysis the stability of this scheme, the amplification matrix is derived. The effect of wave propagation direction on the stability of this scheme is investigated. The numerical dispersion relation of this scheme is also derived analytically from the amplification matrix. From the theoretical stability analysis and numerical simulation, it is found that the Mur's first order ABC in the ADI-FDTD method will be unstable.
Analysis of stability and numerical dispersion relation of Mur's absorbing boundary condition in the ADI-FDTD method
(2007)
Hwang, Jiunn-Nan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
In this paper, the stability analysis of the Mur's first order absorbing boundary condition (ABC) in the alternating direction implicit finite-difference time-domain (ADI-FDTD) method is presented. To analysis the stability of this scheme, the amplification matrix is derived. The effect of wave propagation direction on the stability of this scheme is investigated. The numerical dispersion relation of this scheme is also derived analytically from the amplification matrix. From the theoretical stability analysis and numerical simulation, it is found that the Mur's first order ABC in the ADI-FDTD method will be unstable.
Analysis of stability and numerical dispersion relation of Mur's absorbing boundary condition in the ADI-FDTD method
(2007-01-01)
Hwang, Jiunn-Nan
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
In this paper, the stability analysis of the Mur's first order absorbing boundary condition (ABC) in the alternating direction implicit finite-difference time-domain (ADI-FDTD) method is presented. To analysis the stability of this scheme, the amplification matrix is derived. The effect of wave propagation direction on the stability of this scheme is investigated. The numerical dispersion relation of this scheme is also derived analytically from the amplification matrix. From the theoretical stability analysis and numerical simulation, it is found that the Mur's first order ABC in the ADI-FDTD method will be unstable.
Asymmetric Coplanar Waveguide (ACPW) Zeroth-Order Resonant (ZOR) Antenna With High Efficiency and Bandwidth Enhancement
(2012)
Chen, Po-Wei
;
Chen, Fu-Chiarng
;
電機工程學系
;
Department of Electrical and Computer Engineering
"A novel low-profile zeroth-order (ZOR) antenna is presented. The feature of ZOR based on periodic structures is employed to reduce the antenna size, while these antennas generally suffer from narrow bandwidth. A single-layer asymmetric coplanar waveguide (ACPW) structure is proposed to realize a bandwidth-extended ZOR antenna, where the antenna bandwidth is characterized by an equivalent circuit model. The ACPW-structure not only provides the design freedom, but also overcomes the design constraint of the traditional CPW. The ACPW ZOR antenna is verified by both full-wave simulations and experiments. As an advantage of the proposed method, the size of antenna is reduced, and the resonant frequency of zeroth-order mode is 1.94 GHz with radiation efficiency of 85%, measured 10-dB fractional bandwidth up to 10.3%, and omnidirectional peak gain of 2.3 dBi."
Compact Printed Hepta-Band Monopole Antenna for Mobile Devices
(2010-01-01)
Chi, Yu-Jen
;
Chen, Fu-Chiarng
;
電機學院
;
電機工程學系
;
College of Electrical and Computer Engineering
A novel compact internal hepta-band planar monopole antenna for mobile devices is presented. The antenna element occupy 35.5 mm x 15.5 mm and is installed on a small ground plane which is only 35.5 mm x 60 mm Multi-resonant operation is achieved by one radiator which is comprised of two branches and a floating coupled element on the back side of the substrate. The achieved bandwidth of the proposed antenna covers nine wireless standards such as GSM, GPS, DCS, PCS, UMTS, Bluetooth, WLAN, WiMAX 2.5 GHz and WiMAX 3.5 GHz. Antenna parameters are presented to validate the proposed antenna. Low profile design is very suitable for multiband mobile communication systems.
Comparison of MIMO Spatial Correlation Approximations under Large Angular Spread
(2008)
Chuang, Jui-Ting
;
Chen, Fu-Chiarng
;
電信工程研究所
;
Institute of Communications Engineering
COPLANAR ANTENNA UNIT AND COPLANAR ANTENNA
(2011-02-17)
Chen, Fu-Chiarng
;
Kao, Cheng-Lung
The present invention is related to a coplanar antenna unit and a coplanar antenna. By utilizing the unique properties of meta-material to design 1-D balanced CRLH leaky-wave antenna. The antenna can be realized with the coplanar antenna unit consisting of MIM capacitor and grounded inductor. In this invention, all proposed elements are implemented by planar print circuit broad, so the full-space switched beam scanning antenna has shorter length of leaky-wave antenna and good radiation performance.