Browsing by Author "Chi, Pei-Ling"

Now showing 1 - 20 of 48

A 1.1-3.1-GHz Tunable Quadruplexer with Compact Size and Bandwidth Control
(2019-01-01)
Chi, Pei-Ling
;
Chi, Yu-Wen
;
Yang, Tao
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes a varactor-tuned quadruplexer that allows simultaneous control of the center frequency and bandwidth of each channel and independent control on different channels. To achieve compactness, each channel consists of only a dual-mode resonator where the even- and odd -mode resonances contribute to a two -pole response. The fabricated prototype shows that, for the input return loss greater than 10 dB, the available tuning ranges of the channel frequency and the 3 -dB bandwidth are 1.1-1.4 GHz and 100-140 MHz, 1.55-1.9 GHz and 120-150 NIIIz, 2.05-2.4 GlIz and 190-240 MHz, and 2.63-3.1 GlIz and 240270 NHIz, respectively, for channels 1, 2, 3, and 4. The channel insertion loss is less than 5 dB and isolation is greater than 25 dB for all tuning states. The quadruplexer has a footprint of 0.45 lambda(g) x 0.25 lambda(g), where lambda(g) is the guided wavelength at 1.1 GHz.
A 1.16-3.89-GHz Tunable Six-Channel Diplexer with Compact Size and High Isolation
(2019-01-01)
Chi, Pei-Ling
;
Chiou, Ching-Kai
;
電機工程學系
;
Department of Electrical and Computer Engineering
A compact microstrip varactor-based diplexer with six tunable channels is proposed. Each output path contains only two varactor-loaded multi-mode resonators, by which three two-pole passbands/channels can be independently and continuously tuned over a wide bandwidth. Given the input return loss greater than 10 dB and output isolation greater than 26.1 dB, the six channels of the fabricated diplexer can be experimentally tuned in the range of 1.16 similar to 1.36, 1.65 similar to 1.81, 2.05 similar to 2.36, 2.57 similar to 2.86, 3 similar to 3.52, and 3.3 similar to 3.89 GHz, respectively. Measured results agree well with simulated results.
A 1.3-2.08 GHz Filtering Power Divider With Bandwidth Control and High In-Band Isolation
(2016-06)
Chi, Pei-Ling
;
Yang, Tao
;
電機學院
;
College of Electrical and Computer Engineering
This letter proposes a varactor-based filtering power divider that allows for reconfigurable operating frequency and bandwidth with high in-band isolation. A simple but effective tuning scheme was used to attain good impedance matching and isolation for all tunable states. Experimental results show that, for input return loss > 16.6 dB, the center frequency and 1 dB constant absolute bandwidth can be tuned from 1.3 to 2.08 GHz and from 70 to 130MHz, respectively. Moreover, this work demonstrates > 26 dB output isolation, < +/- 0.23 dB magnitude imbalance, and < +/- 1.3 degrees phase imbalance. Measured and simulated results are in good agreement.
A 39 GHz Reflection-Type Phase Shifter for Reflectarray Antenna Application
(2019-01-01)
Lin, Yu-Ting
;
Hsiao, Chiao-Yun
;
Chi, Pei-Ling
;
Kuo, Chien-Nan
;
交大名義發表
In this paper, a differential one-port millimeter-wave reflection-type phase shifter for reflectarray antenna applications is implemented in 90 urn CMOS technology. Assisted by a switched terminator, the measured phase shift achieves more than 360 degrees using voltage control from 0 to 1 V. Signal loss is compensated in this design to alleviate the loss issue of passive phase shifters. The circuit consumes de power of 14.4 mW.
A Fully Tunable Two-Pole Bandpass Filter
(2015-05-01)
Chi, Pei-Ling
;
Yang, Tao
;
Tsai, Tsung-Ying
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
In this letter, a two-pole tunable combline filter that allows for operational agility of the center frequency, passband bandwidth, and locations of upper and lower transmission zeros is proposed. To increase the tunable range of constant absolute-bandwidth for all frequency tuning states, a novel T-type bandwidth-control network was devised between resonators to flexibly tune the coupling coefficient without limitations imposed by the available varactor capacitance. By use of tunable source-load coupling, two tunable transmission zeros were produced on both sides of the passband to significantly improve filter selectivity and to dynamically afford interference suppression. A second-order 1.7-2.7 GHz filter with 1 dB constant bandwidth tuning from 50 to 110 MHz and transmission zero locations tuning from 300 to 700 MHz with respect to the passband was developed and fabricated. Good agreement was obtained between the simulated and experimental results.
A pi-type Isolation Network for Improvement of Matching and Isolation in Reconfigurable Multifunctional Bandpass Filter
(2019-01-01)
Zhu, Xu
;
Yang, Tao
;
Chi, Pei-Ling
;
Xu, Ruimin
;
交大名義發表
In this paper, a method for improving the output impedance match and isolation between output ports of the reconfigurable single-to-balanced (SE-BAL), power-dividing (PD) and single-ended (SE) multifunctional filter is presented. By adding the varactor-tuned pi-type isolation network to the outputs of the tunable multifunctional filter, both the matching and isolation at the output ports are improved to a large degree over the full tuning range. Compared to the original standalone multifunctional filter, the measured output return loss and isolation of the filter with pi-type isolation network are improved by more than 10 dB at center frequency of each tuning state under the SE-BAL and PD filtering mode, while the measured output return loss and isolation for the SE filtering mode still keeps better than -20 dB in the whole tuning range.
A Reconfigurable In-Phase/Out-of-Phase and Power-Dividing Ratio Power Divider
(2017-01-01)
Chi, Pei-Ling
;
Chi, Yu-Wen
;
Yang, Tao
;
資訊工程學系
;
電機工程學系
This paper presents a varactor-based power divider with reconfigurable power-dividing ratio and reconfigurable in-phase or out-of-phase phase relation between outputs. By properly controlling the tuning varactors, the power divider can be either in phase or out of phase and each with a wide range of tunable power-dividing ratio. The proposed microstrip power divider was prototyped and experimentally characterized. Measured and simulated results are in good agreement.
A Tunable Balanced Coupler With Improved Phase Balance and Extended Bandwidth
(2019-01-01)
Chi, Pei-Ling
;
Lin, Hong-Min
;
Chien, Chun-Pin
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes a balanced coupler with improved phase balance and extended bandwidth for a wide range of tunable power-dividing ratios. This differential coupler uses only two varactors and can demonstrate tunable power-dividing ratio and quadrature phase difference between outputs with theoretically perfect differential-mode return loss and port isolation, and complete common-mode suppression. The coupler analysis, design equations/graph, and parametric study will be given in detail. As a proof-of-concept, a microstrip prototype operating at 1 GHz was fabricated. Measured results show that the power-dividing ratio can be tuned from -5.5 dB to 11.9 dB at the center frequency where the insertion loss is less than 0.84 dB, the phase imbalance and isolation between differential outputs are less than 3.9 degrees and greater than 23.2 dB, respectively. Moreover, the differential-mode return loss and the common-mode rejection are greater than 27.5 dB and 35.2 dB, respectively. Measured and simulated results are in good agreement.
A Wide Impedance Bandwidth Printed Slot Antenna for 28, 38, and 60-GHz Applications
(2018-01-01)
Chi, Pei-Ling
;
Wang, Ching-Hsiang
;
電機工程學系
;
Department of Electrical and Computer Engineering
A printed slot antenna with 10-dB impedance bandwidth from 22.44 GHz to > 67 GHz is presented. The proposed antenna is basically an elliptical slot antenna fed by a microstrip line on the backside of the substrate. To increase the bandwidth, particularly, a parasitic patch loaded by a cross shaped slot was non-concentrically placed into the elliptical slot and an open-circuited stub was properly added to the feed line. Experimental results show that the fabricated antenna achieves a ratio bandwidth of > 2.99:1 for VSWR <= 2 and at lower frequencies of the bandwidth it exhibits dipole-like radiation patterns with the peak gain of 8.4 dBi. The proposed antenna is suited to future 5G wireless communications at 28 GHz, 38 GHz, and 60 GHz.
Balanced-to-Balanced Power Divider with Tunable In-Phase/Out-of-Phase Power-Dividing Ratio
(2018-01-01)
Chi, Pei-Ling
;
Chien, Chun-Pin
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper presents a balanced-to-balanced microstrip power divider with a wide range of continuously tunable power-dividing ratios for either in-phase or out-of-phase outputs. Based on simple design equations, the proposed power divider can theoretically attain ideal mixed-mode responses, including the in-phase and out-of-phase designs, for an arbitrary power ratio by a proper control of the used varactor capacitances. A single-layer power divider was prototyped and measured. Given the differential-mode return loss and output isolation greater than 15 dB, the power-dividing ratio was tuned from 11.1 dB to 24.2 dB and from 1.3 dB to 21.1 dB for the in-phase and out-of-phase outputs, respectively. For all states, the common-mode suppression achieved greater than 63.9 dB at the center frequency.
Bandwidth-Enhanced Branch-Line Coupler Using the Center-Loaded Vertical Line and Distributed Capacitors
(2012)
Chen, Tse-Yu
;
Chi, Pei-Ling
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
In this paper, the technique that loads the center of the horizontal transmission lines in a conventional branch-line coupler by a vertical line section as well as the distributed capacitors is presented to enhance the coupler bandwidths. Based on the proposed structure, the numerical solution derived from the even/odd-mode decomposition analysis for optimized bandwidth enhancement is applied for structural parameters. Experimental results show that the developed 90 degrees coupler demonstrates more than 11% return-loss/isolation bandwidth increase as compared to the conventional quadrature hybrid. Furthermore, the 3dB +/- 1dB magnitude- and 90 degrees +/- 5 degrees phase-difference bandwidths are 3% and 14% increased, respectively.
Compact and Bandwidth-Enhanced Zeroth-Order Resonant Antenna
(2015-01-01)
Chi, Pei-Ling
;
Shih, Yi-Sen
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
In this letter, a simple bandwidth-enhanced zeroth-order resonant (ZOR) antenna is proposed. The presented antenna is composed of two unit cells of the composite right/left-handed (CRLH) artificial structure and operates in the series resonant mode. In order to enhance the operational bandwidth, in particular, the interdigital capacitor in a unit cell was properly designed so as to reduce the quality factor of the resonator while occupying a relatively small area. Additionally, to facilitate implementation of the short-circuited boundary condition, the coplanar waveguide (CPW) was applied to develop a via-less uniplanar antenna prototype. Experimental results show that the presented ZOR antenna achieves a 10-dB bandwidth of 15.1% and a peak radiation gain of 1.62 dBi with a compact size of 0.14 lambda(o) x 0.22 lambda(o) at the operating frequency. Measured and simulated results are in good agreement.
Compact and Dual-Band Arbitrary Power-Split Quadrature Coupler Using the Composite Right/Left-Handed Transmission Lines
(2014)
Chi, Pei-Ling
;
Chang, Wen-Yuan
;
資訊工程學系
;
電機學院
;
Department of Computer Science
In this paper, a dual-band quadrature coupler is proposed for arbitrary power divisions using the composite right/left-handed (CRLH) transmission lines. The presented prototype is based on two identical CRLH transmission lines of 50 ohm and a pair of lumped-element parallel tanks loaded to the CRLH host lines. The power division ratio at either frequency is determined by the electrical length of the 50-Omega CRLH lines, which facilitates coupler realization of arbitrary power split, even for a large division ratio. By applying the CRLH lines, the dual operating frequencies as well as the corresponding power split ratios can be arbitrarily designed, which on the contrary is infeasible by microstrip lines. Two coupler prototypes were developed for power division ratios of 10/10 dB and 10/6 dB at 0.9/1.8 GHz. In particular, the first fabricated coupler occupies only 18% footprint of the 0.9-GHz microstrip branch-line coupler. Experimental results are in good agreement with simulation data.
Compact Circularly-Polarized Slot Antenna with Enhanced Impedance and Axial-Ratio Bandwidths
(2019-01-01)
Chi, Pei-Ling
;
Huang, Ming-Hui
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes a compact circularly-polarized slot antenna with enhanced impedance and axial-ratio bandwidths. To substantially increase the axial-ratio bandwidth, the microstrip feedline is asymmetrically placed underneath the slot and several metal stubs are protruded from slot perimeter to introduce proper current distribution along two orthogonal directions. The antenna prototype achieves the measured 10-dB impedance bandwidth, the 3-dB axial-ratio bandwidth, and the peak gain of 120.8%, 95%, and 4.33 dBic, respectively. This antenna has a compact size of 0.315 lambda(0) x0.315 lambda(0) x0.02 lambda(0) at the lowest operating frequency.
Compact Zeroth-Order Resonant Antenna Based on Dual-Arm Spiral Configuration
(2012)
Liu, Chun-Chih
;
Chi, Pei-Ling
;
Lin, Yu-De
;
電機工程學系
;
Department of Electrical and Computer Engineering
A miniaturized and zeroth-order resonant composite right/left-handed (CRLH) antenna based on dual-arm spiral structure is presented. The proposed dual-arm spiral unit cell is able to implement and tailor the CRLH lumped elements easily in a compact fashion. Particularly, the gap coupling between the spiral arms contributes to the series capacitance C-L and the metallic via-hole at the end of one arm results in the shunt inductance L-L. The resonant frequency and thus the miniaturization factor can be simply engineered by the spiral parameters that determine the corresponding circuit elements. The proposed CRLH antenna is composed of two unit cells, each of which occupies only 0.066 lambda(0) x 0.053 lambda(0) at the operating frequency. From the experimental results, this compact antenna exhibits the dipole-like radiation patterns and has a peak gain of -0.53 dBi. The measured and simulated results are provided, and good agreement is achieved.
Design of Dual-Band Coupler With Arbitrary Power Division Ratios and Phase Differences
(2014-12-01)
Chi, Pei-Ling
;
Ho, Kuan-Lin
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
This paper presents, for the first time, a directional coupler that allows for arbitrary power division ratios as well as arbitrary phase differences at dual frequencies of interest. Explicit design equations in terms of dual-band power-dividing ratios and phase differences will be given here and were derived based on the even-and odd-mode decomposition analysis. To illustrate the design procedure, examples will be provided and the relevant studies on the coupler\'s electrical parameters for a wide range of dual-band specifications and frequency ratios were conducted, by which the graphical solutions can be readily used as the further design tool. In addition, the resulting operational bandwidths are included and discussed for completeness. To validate our idea, four coupler prototypes were carried out according to the given guidelines. Excellent agreement is obtained between the measured and full-wave calculated results. The functional versatility of the proposed simple structure is well suited to applications in dual-band integrated modules, such as the beam-forming networks, for both loss and size reduction.
Dual-Band Ring Coupler Based on the Composite Right/Left-Handed Folded Substrate-Integrated Waveguide
(2014-05-01)
Chi, Pei-Ling
;
Chen, Tse-Yu
;
電機資訊學士班
;
Undergraduate Honors Program of Electrical Engineering and Computer Science
In this letter, a dual-band ring coupler based on the folded substrate-integrated waveguide (FSIW) is proposed. The artificial structure, the composite right/left-handed (CRLH) transmission lines were implemented in the FSIW by loading the interdigital capacitors in the middle metallic layer to generate a left-handed passband region below the cutoff frequency of the ordinary waveguide mode for coupler miniaturization. The FSIW is the folded counterpart of the substrate-integrated waveguide (SIW) and thus can prevent the CRLH transmission lines from radiation loss by shielding the interdigital capacitors in the waveguide. Besides, the FSIW-based coupler is able to eliminate the electromagnetic interference (noise) with adjacent objects and lend itself to multilayer circuit integration. A ring coupler that operates at 4.3 and 7.6 GHz was developed and experimentally verified. To the best of the authors\' knowledge, it is the first time that a dual-band rat-race was implemented and reported based on the CRLH-FSIW structure.
Folded Substrate Integrated Waveguide Based Composite Right/Left-Handed Transmission Line and Its Application to Partial H-Plane Filters
(2013-02-01)
Yang, Tao
;
Chi, Pei-Ling
;
Xu, Ruimin
;
Lin, Weigan
;
電機資訊學士班
Composite right/left-handed (CRLH) transmission line structures based on the folded substrate integrated waveguide (FSIW) are presented and discussed in this paper. This FSIW-based CRLH (FSIW-CRLH) transmission line exhibits much lower cut-off frequencies as compared to the ordinary FSIW of the same footprint, and furthermore, it requires only one-half width of the conventional substrate integrated waveguide (SIW) based CRLH (SIW-CRLH) transmission lines while possessing the same dispersion characteristics. In addition, the proposed structure offers the advantage of a high quality factor for preventing the guided-wave circuits from radiation as suffered in the previous open CRLH transmission line structures when operated in the fast-wave region. All of the aforementioned properties lend the proposed FSIW-based CRLH transmission lines best suited to miniaturized and guided-wave microwave applications. In this paper, a comprehensive study on the FSIW-CRLH transmission structures is conducted by means of its dispersion relation and Bloch impedance. In addition, two partial H-plane filters are implemented here to demonstrate the capabilities of miniaturization and high quality factor based on the proposed FSIW-CRLH structures. The resultant filters are shown to have about 80% size reduction as compared to the conventional FSIW filters, and 59% size reduction as compared to the SIW-CRLH filters. To the best of our knowledge, it is the first time that the partial H-plane filters are implemented utilizing both the dispersion behavior of the CRLH transmission structures and the structural benefits of the FSIW configuration.
High-Gain Patch-Fed 3D-Printing Fresnel Zone Plate Lens Antenna for 60-GHz Communications
(2018-01-01)
Chi, Pei-Ling
;
Pao, Chi-Hsien
;
Huang, Ming-Hui
;
Yang, Tao
;
電機工程學系
This paper presents a high-gain Fresnel zone plate lens antenna designed for 60-GHz systems. Manufactured with the 3D printing technology and fed by a simple patch on the substrate, the proposed Fresnel lens antenna allows for low-cost fabrication and easy integration with planar circuitry. Experimental results show that the prototype antenna can achieve a 10-dB impedance bandwidth from 56.6 GHz to > 67 GHz and the peak gain of 14 similar to 20 dBi across the bandwidth, corresponding to gain enhancement of 9.2 similar to 10.9 dB.
Highly Reconfigurable Quadrature Coupler With Ideal Impedance Matching and Port Isolation
(2017-08-01)
Chi, Pei-Ling
;
Hsu, Ting-Chen
;
電機工程學系
;
Department of Electrical and Computer Engineering
This paper proposes a varactor-based coupler structure that allows for reconfigurable operating frequency, power-dividing ratio, and coupler to/from crossover responses. Particularly, this coupler can theoretically realize perfect impedance matching and port isolation at all tuning states. The coupler analysis, design equations, and design graphs were conducted, given, and discussed in detail. For demonstration purposes, two prototypes were experimentally developed and characterized. The first quadrature coupler demonstrates a frequency-tuning range from 0.632 to 1.5 GHz with a constant power-dividing ratio of -3 dB, <2.3 degrees phase imbalance, >20-dB isolation, and >14-dB return loss. In the second prototype, for the phase error <6.7 degrees, isolation and return loss >19 dB, the power-dividing ratio was tuned from -6.4 to 20.5 dB at 1 GHz, yielding a 26.9-dB tuning range and crossover characteristics at low bias voltages. Measured and simulated results are in good agreement.