Browsing by Author "Chiou, Yi-Chyun"

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Analysis and Design of Double-Ring Crossover Junction With Arbitrary Diagonal Port Impedances
(2009)
Chiou, Yi-Chyun
;
Lai, Shih-Wei
;
Kuo, Jen-Tsai
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傳播研究所
;
Institute of Communication Studies
A planar four-port double-ring crossover junction with arbitrary diagonal port impedances is designed and realized. The circuit consists of two concentric rings connected with four transmission line sections. It allows the two pairs of diagonal ports of the junction to have different characteristic impedances. Based on the transmission-line theory, design equations are formulated and design curves are provided. Two microstrip circuits are realized to validate the idea. One operates at 2.45 GHz and the other at 5.2 GHz. Both circuits have excellent performance such as good return loss and isolation. The measured total power loss is less than 4.8%. The measured results agree very well with simulation counterparts.
Broadband quasi-Chebyshev bandpass filters with multimode stepped-impedance resonators (SIRs)
(2006-08-01)
Chiou, Yi-Chyun
;
Kuo, Jen-Tsai
;
Cheng, Eisenhower
;
電信工程研究所
;
Institute of Communications Engineering
Planar broadband bandpass filters of order up to 9 are synthesized based on the multimode property of stepped-impedance resonators (SIRs). Based on the transmission line theory, the modal frequencies of the SIRs are calculated based on the impedance and length ratios of its hi- and low-Z segments. In the synthesis, the SIR coupling schemes are determined by the split mode graphs. Using one, two, two, three, and three dual- or triple-mode SIRs, quasi-Chebyshev filters with,, six, six, eight, and nine transmission poles, respectively, are four synthesized with a fractional bandwidth (BW) Delta = 50%. Emphasis is placed not only on designing the I/O coupling structures for matching the external Q (Q(ext)) and the circuit BW, but also on matching the resonant peaks of the circuit, with. the nominal Chebyshev poles. Measured results of experimental circuits show good agreement with simulated responses.
Comments on "A Symmetrical Four-Port Microstrip Coupler for Crossover Application"
(2009-07-01)
Chiou, Yi-Chyun
;
Tsai, Cheng-Hsiu
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Kuo, Jen-Tsai
;
電信工程研究所
;
Institute of Communications Engineering
Compact Hairpin Resonator Bandpass Filters with Dual-Band Response and Wide Upper Stopband
(2009)
Hsieh, Ping-Yueh
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Chiou, Yi-Chyun
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Kuo, Jen-Tsai
;
Lok, U. Hou
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傳播研究所
Compact bandpass filters are devised with a dual-passband response and a wide upper stopband based on hairpin resonators with three shunt open stubs; one is tapped at its center and the other two are allocated on both sides symmetrically. By adjusting the stub lengths, all resonators are designed to have two identical leading resonant frequencies but different higher-order ones. To enhance the rejection level and extend the upper stopband, the transmission zeros created by the tap structures and the coupled-line stages are used to eliminate the remaining leading unwanted peaks. In addition, a method for reducing the radiation loss in upper stopband is investigated. Measured results show that the fifth-order filter has a rejection level below 30 dB can be extended to six times the first frequency. Good agreement between measured and simulation is obtained.
Compact miniaturized stepped-impedance low-pass filters with a broad stopband
(2005)
Chiou, Yi-Chyun
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Kuo, Jen-Tsai
;
Chen, Jacob
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電信工程研究所
;
Institute of Communications Engineering
Stepped-impedance low-pass filters (LPFs) are designed to have a miniaturized area and good rejection in wide stopband. The low-Z sections are implemented by microstrips loaded with periodic open-circuit stubs. Adjacent low-Z sections have a strong capacitive coupling through an interdigitated configuration. Equivalent circuit model for the interdigital capacitor is established for CAD purpose. In the stopband of the LPF, through adjusting the capacitance value, two or three transmission zeros can be realized. To enhance the circuit performance in the stopband, a higher-order filter is made by cascading two third-order LPFs with different cutoff frequencies. These filters present not only a broad stopband but also good insertion loss in the passband. Measured results of four fabricated circuits show good agreement with data obtained by circuit analysis and simulation by commercial 3D EM software package.
Compact Stepped-Impedance Resonator Bandpass Filter with Two Wide Spread Passbands
(2008)
Chiou, Yi-Chyun
;
Hsieh, Ping-Yueh
;
Kuo, Jen-Tsai
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電信工程研究所
;
Institute of Communications Engineering
This paper presents the design method for a compact dual-band bandpass filter with a large ratio of center frequencies. Emphasis is placed on circuit synthesis for simultaneously matching the in-band responses at the two designated passbands. In an interdigital configuration, a 0.9/5.8 GHz bandpass filter is designed and fabricated. It is believed that this is the filter has the largest ratio of the center frequencies in comparison with those in open literature. The measured responses show good agreement with the simulation results.
Compact UWB bandpass filter using stub-loaded multiple-mode resonator
(2007-11-01)
Chiou, Yi-Chyun
;
Kuo, Jen-Tsai
;
電信工程研究所
;
Institute of Communications Engineering
Design of Compact Symmetric Four-Port Crossover Junction
(2009-09-01)
Chiou, Yi-Chyun
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Kuo, Jen-Tsai
;
Lee, Hsuan-Rong
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電信工程研究所
;
Institute of Communications Engineering
Performance of a fully planar four-port crossover coupler is investigated. This bisymmetric circuit consists of a ring and two inner orthogonal sections connecting the diagonal ports. Based on the transmission line theory, analysis equations are formulated and design curves are presented. Two crossover junctions are fabricated and measured for validity confirmation. The measured data have good agreement with simulation.
Distributed and Lumped-Element Realizations of Wideband Branch-Line Hybrids with Arbitrary Power Division
(2009)
Lin, Tsu-Wei
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Chiou, Yi-Chyun
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Kuo, Jen-Tsai
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傳播研究所
;
Institute of Communication Studies
A two-section branch-line coupler with an arbitrary output power division is realized by lumped and distributed elements. Based on the transmission line theory, as well as the basic circuit theory, transcendental equations are derived and formulated to determine its circuit parameters. For circuit miniaturization, the transmission-line sections are replaced by either a lumped pi-network and realized with lumped capacitors. Several design curves are provided for ease of circuit implementation. Two circuits with output power division ratios vertical bar Delta vertical bar= 3 dB are fabricated and measured.
DUAL-BAND COUPLER UNIT AND DUAL-BAND COUPLER THEREOF AND RECEIVER THEREOF
(2010-12-16)
Kuo, Jen-Tsai
;
Chiou, Yi-Chyun
;
Chan, Chi-Hung
A dual-band coupler unit is provided. The dual-band coupler unit includes a first coupled line, a second coupled line, a short transmission line, a first transmission line, and a second transmission line. The first coupled line and the second coupled line are substantially in parallel with each other, and are substantially of the same length. One end of the short transmission line is connected to one end of the first coupled line, and the other end of the short transmission line is connected to one end of the second coupled line. One end of the first transmission line is connected to the other end of the first coupled line, and one end of the second transmission line is connected to the other end of the second coupled line.
Dual-Band Rat-Race Coupler With Arbitrary Power Divisions Using Microwave C-Sections
(2009)
Wu, Cho-Yu
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Chiou, Yi-Chyun
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Kuo, Jen-Tsai
;
傳播研究所
;
Institute of Communication Studies
Rat-race coupler is designed to have dual-band operation, a miniaturized area, and arbitrary power division using microwave C-sections. With a C-section and two transmission line sections attached to both of its ends, an elementary two-port is designed to play the role of a quarter-wave section in a conventional rat-race. It is designed to possess phase changes of 90 degrees and 270 degrees at the first and second frequencies, respectively. Transcendental equations are derived for calculating its structure parameters. Two circuits operating at 2.45/5.8 GHz with various output power ratios are fabricated and measured. Both couplers have only 31% area of conventional rat-race at the first band. It is believed that these circuits have the best size reduction for microstrip dual-band rat-race with arbitrary power division in open literature. Measured results agree well with their simulation counterparts.
Extraction of Electric and Magnetic Coupling for Coupled Symmetric Microstrip Resonator Bandpass Filter with Tunable Transmission Zero
(2009)
Tang, Shao-Chan
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Yu, Cheng-Hsuan
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Chiou, Yi-Chyun
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Kuo, Jen-Tsai
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傳播研究所
An effective approach is demonstrated for extracting the electric and magnetic coupling components from the coupling coefficient between two coupled symmetric microstrip resonators. It is found that the extraction provides an extra degree of freedom for circuit design. A transmission zero near passband can be created without any cross-coupling scheme but by properly selecting the parameters of the resonators. An equivalent circuit is derived for characterizing the extraction of the coupling and control of the zero. Two experimental filters are realized and measured to validate the approach.
High Selectivity Ultra-Wideband (UWB) Mutimode Stepped-Impedance Resonators (SIRs) Bandpass Filter with Two-Layer Broadside-Coupled Structure
(2007)
Kuo, Jen-Tsai
;
Chiou, Yi-Chyun
;
Cheng, Eisenhower
;
電信工程研究所
;
Institute of Communications Engineering
Ultra-wideband (UWB) bandpass filter with high selectivity response is contrived on the multimode characteristic of stepped-impedance resonators (SIRs). To achieve strong coupling requirement, two-layer broadside-coupled structure is employed. Using three triple-mode SIRs, quasi-Chebyshev filter with nine transmission poles is synthesized with a fractional bandwidth (BW) Delta = 110%. Measured results of experimental circuits show good agreement with simulated responses.
Miniaturization Design for Planar Hybrid Ring Couplers
(2008)
Chiou, Yi-Chyun
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Tsai, Cheng-Hsiu
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Wu, Juo-Shiuan
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Kuo, Jen-Tsai
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電信工程研究所
Miniaturization of a microstrip rat race coupler is implemented by three approaches. First, a new rat race hybrid design is devised for circuit miniaturization based on the periodic stepped-impedance ring structure. The circuit has a normalized area of 21.5%. In the second approach, miniaturization is carried out by incorporating a broadside-coupled structure and stepped-impedance sections into the design. The former is used to replace the 3 lambda/4-section and the latter is to substitute each lambda/4-section in the regular 6 lambda/4 circuits. As a result, one of the circuits occupies only 18% of the area of a traditional rat race. Finally, a general synthesis is performed to design reduced-length rat race rings. Incorporating the stepped-impedance configuration, the normalized circuit area is 13.12% of a 6 lambda/4-ring. All the designs are validated by comparing measured four-port parameters with the simulated results.
Miniaturized 7 lambda/6 Rat Race Coupler with Microstrip-to-CPW Broadside-Coupled Structure and Stepped-Impedance Sections
(2008)
Chiou, Yi-Chyun
;
Wu, Juo-Shiuan
;
Kuo, Jen-Tsai
;
電信工程研究所
;
Institute of Communications Engineering
Miniaturization of the rat race coupler is implemented by incorporating a microstrip-to-coplanar waveguide (CPW) broadside-coupled structure and stepped-impedance line sections into the design. The former is used to replace the 4 lambda/6-section and the latter is to substitute the lambda/6-sections in a 7 lambda/6-rat race. The circuit occupies only 8.9% of the area of a traditional rat race of 3 lambda/2 circumference. It is believed that it has the best size reduction in comparison with those in open literature. Measurement results are shown to validate the design and theoretical prediction.
Miniaturized Quadruple-Mode Periodic Stepped-Impedance Coupled-Ring Resonator Bandpass Filter With a Sharp Transition Band and a Wide Stopband
(2008)
Chiou, Yi-Chyun
;
Yang, Ping-Shiang
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Kuo, Jen-Tsai
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電信工程研究所
;
Institute of Communications Engineering
Miniaturized rat race coupler with microstrip-to-CPW broadside-coupled structure and stepped-impedance sections
(2007)
Kuo, Jen-Tsai
;
Chiou, Yi-Chyun
;
Wu, Juo-Shiuan
;
電信工程研究所
;
Institute of Communications Engineering
Miniaturization of microstrip rat race coupler is implemented by incorporating a broadside-coupled structure and stepped-impedance line sections into the design. The former is used to replace the 3 lambda/4-section and the latter is to substitute the lambda/4-line in the conventional circuit. No lumped-element is required in the circuit. One of the experimental circuits occupies only 18.3% of the area of a traditional 6 lambda/4-rat race. It is believed that it has the best size reduction in comparison with those in open literature. In addition to a wideband characteristic, total inband power loss is better than 3.2%. Measurement results are shown to validate the design and theoretical prediction.
Miniaturized rat race coupler with suppression of spurious passband
(2007-01-01)
Kuo, Jen-Tsai
;
Wu, Juo-Shiuan
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Chiou, Yi-Chyun
;
電信工程研究所
;
Institute of Communications Engineering
A new hybrid ring coupler design is devised for circuit miniaturization based on the periodic stepped-impedance ring resonator structure. The circuit has an area of 21.5 % of a conventional rat race coupler and no passband up to the sixth harmonic of the design frequency. The designs are validated by comparing measured four-port parameters with the simulated results.
New Miniaturized Dual-Band Rat-Race Coupler With Microwave C-Sections
(2009)
Chiou, Yi-Chyun
;
Kuo, Jen-Tsai
;
Chan, Chi-Hung
;
電信工程研究所
;
Institute of Communications Engineering
Based on microwave C-sections, rat-race coupler is designed to have a dual-band characteristic and a miniaturized area. The C-section together with two transmission line sections attached to both of its ends is synthesized to realize a phase change of 90 degrees at the first frequency, and 270 degrees at the second passband. The equivalence is established by the transmission line theory, and transcendental equations are derived to determine its structure parameters. Two circuits are realized in this presentation; one is designed at 2.45/5.2 GHz and the other at 2.45/5.8 GHz. The latter circuit occupies only 31% of the area of a conventional hybrid ring at the first band. It is believed that this circuit has the best size reduction for microstrip dual-band rat-race couplers in open literature. The measured results show good agreement with simulation responses.
New Miniaturized Dual-Mode Dual-Band Ring Resonator Bandpass Filter With Microwave C-Sections
(2010-02-01)
Chiou, Yi-Chyun
;
Wu, Cho-Yu
;
Kuo, Jen-Tsai
;
傳播研究所
;
Institute of Communication Studies
A new miniaturized dual-mode dual-band ring resonator bandpass filter is implemented by a cascade of several microwave C-sections. Each C-section is used to substitute a transmission line section of designated electrical length. Through proper design of input/output coupling configuration, two transmission zeros can be created on both sides of each passband. Two circuits with four and six microwave C-sections are fabricated for confirmation. They occupy less than 30% of the area of a traditional ring resonator filter. Measured responses agree very well with the simulation.