Compact Bandpass Filter Based on Parallel-coupled Lines and Quasi-lumped Structure

Frequenz ◽  
2016 ◽  
Vol 70 (1-2) ◽  
Author(s):  
Chen Ding ◽  
Jiao Li ◽  
Feng Wei ◽  
Xiao-Wei Shi
Keyword(s):  
Bandpass Filter ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
The Matrix ◽  
Network Transformation ◽  
Good Agreement

AbstractA compact microstrip bandpass filter (BPF) using quarter-wavelength resonators is proposed based on the parallel-coupled lines (PCLs) and quasi-lumped structure. A method based on the matrix and network transformation of cascaded-quadruplet (CQ) filters is investigated and successfully applied to the BPF design. The design formulas for the proposed BPF are analytically developed. Specifically, in order to verify the feasibility of the proposed method, three BPFs centering at 1.575 GHz with different FBWs are designed. Good agreement between the simulated and measured results is observed. Moreover, the designed filters can achieve a wide stopband.

scholarly journals Pseudo-elliptic narrow bandpass filter using shorted coupled-line of higher order design

2019 ◽  
Vol 14 (1) ◽  
pp. 388
Author(s):  
Mohd Nasiruddin Hushim ◽  
Norfishah Ab Wahab ◽  
Muhammad Farid Abdul Khalid ◽  
Tn. Syarifah Atifah Tn. Mat Zin
Keyword(s):  
Bandpass Filter ◽  
Coupled Line ◽  
Transmission Zeros ◽  
Quarter Wavelength ◽  
Measurement Results ◽  
Coupled Lines ◽  
Tan Δ ◽  
Straight Lines ◽  
Good Agreement ◽  
Narrow Bandpass Filter

This paper presents an implementation of quarter wavelength single-shorted coupled-lines for narrow bandpass filter application. It is shown as a new way of creating a single resonance bandpass filter by inter-connected of two <br /> single-shorted quarter wavelength coupled-line sections. By adding more single-shorted coupled-line into the configuration, the form of halfwavelength resonator can increase the degree of order of the filter. For the design of 4<sup>th</sup> order resonator, the coupledlines are arranged inter-connected to each other forming five-fingers lines layout. Due to the interconnection of the coupledlines, transmission zeros appear at the two stopbands which improves the selectivity of the filter response. Investigation on the parametric of the 4<sup>th</sup> order resonator is conducted to observe the controlling parameters and it’s realiability responses of the resonator. For compactness, five-fingers meandered lines is proposed. It is found that the size of the meandered lines resonator was successfully reduced by 33% compared to the five-fingers straight lines resonator of the same order. For validation of concept, the 4<sup>th</sup> order meandered lines resonator was designed at 1 GHz and fabricated on RO3210 microstrip substrate with characteristics given as h = 1.27 mm, Ɛr = 10.2 and tan δ = 3x10<sup>-3</sup>. The measurement results show good agreement with the simulation results.

scholarly journals Closed-loop ring resonator topology for bandpass filter applications

2020 ◽  
Vol 17 (3) ◽  
pp. 1422
Author(s):  
Norfishah Ab Wahab ◽  
M. N. Md Tan ◽  
M. N. Hushim
Keyword(s):  
Transmission Lines ◽  
Closed Loop ◽  
Bandpass Filter ◽  
Ring Resonator ◽  
Single Mode ◽  
Ring Structure ◽  
Transmission Zeros ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
Loop Ring

<p class="Pa41">This paper presents a single mode pseudo-elliptic bandpass resonator based on closed-loop ring topology. The resonator is built from six quarter wavelength transmission lines to form a square closed-loop ring structure. This structure creates transmission zeros at the lower and upper sidebands so that high selectivity bandpass filter response is achieved. The advantage of this topology is that the design is less complex since no perturbation is needed on the ring lines for creation of transmission zeros. Higher-order filters can be constructed by introducing quarter-wavelength coupled-lines, coupled at both input and output of the closed-loop ring resonator. For proof of concept, the filters are designed at 10 GHz up to 3<sup>rd</sup> order, simulated using full-wave electromagnetic simulator on microstrip substrate, <em>FR-4</em> with characteristics given as <em>Ԑr </em>= 4.70, <em>h </em>= 1.499 mm and <em>tan δ </em>= 0.012.  The filters are simulated and responses are found to be agreeable with the proposed idea.</p>

scholarly journals Inter-connected coupled lines Resonator topology for bandpass filter application

2020 ◽  
Vol 10 (3) ◽  
pp. 2523
Author(s):  
Mohd Nasiruddin Hushim ◽  
Norfishah Ab Wahab ◽  
Tn. Syarifah Atifah Tn. Mat Zin ◽  
Norlia Ghazali
Keyword(s):  
Bandpass Filter ◽  
Higher Order ◽  
Coupled Line ◽  
Microstrip Technology ◽  
Half Wavelength ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
In Series ◽  
Tan Δ ◽  
Filter Response

This paper presents an inter-connected side-shorted coupled-line resonator topology as a base cell. The base cell is built from two single-shorted quarter-wavelength coupled-line sections, connected in series to give a half-wavelength coupled-line that creates a single resonance of bandpass filter response. Higher-order bandpass filter is produced by adding new single-shorted coupled-line sections, cascaded in an inter-connected manner to the base cell. This new topology creates a unique arrangement that caused cross coupling effects between the resonators, resulting to the occurrence of transmission zeros that lead to the improvement of selectivity of the higher order bandpass filter response. For validation of concept, 2<sup>nd</sup> and 3<sup>rd</sup> order bandpass filters were fabricated using microstrip technology on Roger 3210 substrate with parameter of <em>Ɛr</em> = 10.2, <em>h</em> = 1.27 mm and <em>tan δ</em> = 3x10-3. The filters were measured and the results show good agreement with simulation results.

Ultra-Wideband (UWB) Bandpass Filter Using Multi-Mode SIR

2013 ◽  
Vol 760-762 ◽  
pp. 241-245
Author(s):  
Jian Kang Xiao ◽  
Wu Zhu ◽  
Yong Li ◽  
Wei Zhao
Keyword(s):  
Return Loss ◽  
Bandpass Filter ◽  
Bandpass Filters ◽  
Ultra Wideband ◽  
Input And Output ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
Multi Mode ◽  
Multiple Transmission

New ultra-wideband (UWB) bandpass filters are proposed by using stepped-impendence resonators (SIRs) and stub-loaded SIRs, aiming at transmitting the signals in the whole UWB passband of 3.1GHz-10.6GHz. Each of the proposed UWB filters consists of two parallel but oppositely arranged compact SIR with tri or quad-section or stub-loaded SIR. In the design, the first two or three resonances of the proposed resonators are properly adjusted to be placed within the UWB. In order to enhance the coupling degree, pairs of quarter-wavelength parallel-coupled lines are longitudinally stretched in both the input and output sides. The UWB bandpass filters behave multiple transmission poles and good return loss of no less than 15dB. A proposed UWB filter is fabricated and measured, and the experiment demonstrates the design.

Parallel-coupled stub-loaded resonator bandpass filter with ultra-wideband passband on multilayer liquid crystal polymer substrates

2015 ◽  
Vol 8 (8) ◽  
pp. 1183-1186 ◽  
Author(s):  
S. Almorqi ◽  
H. Shaman ◽  
A. Alamoudi
Keyword(s):  
Liquid Crystal ◽  
Bandpass Filter ◽  
Liquid Crystal Polymer ◽  
Ultra Wideband ◽  
Center Frequency ◽  
Coupled Line ◽  
Crystal Polymer ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
Chebyshev Filter

A multilayer bandpass filter with ultra-wideband passband is presented in this paper. The filter is designed to have a very wide passband with a fractional bandwidth of about 180% at a center frequency of 10.5 GHz. The filter consists of two sections of parallel-coupled lines loaded at the center with short-circuited stub. Each of the coupled line sections and short-circuited stubs is designed to be a quarter-wavelength long at the desired center frequency. As a result, the filter exhibited a selective filtering characteristic equivalent to a five-pole Chebyshev filter with a very low insertion loss. The proposed filter is realized and fabricated using multilayer liquid crystal polymer substrate. The design is successfully realized in theory and verified by full-wave electromagnetic simulation of the full layout and the experiment where excellent agreement is obtained.

scholarly journals New Cad Model of the Microstrip Interdigital Capacitor

2004 ◽  
Vol 27 (4) ◽  
pp. 237-245 ◽  
Author(s):  
Nihad Dib ◽  
Qiu Zhangb ◽  
Ulrich Rohde
Keyword(s):  
Coplanar Waveguide ◽  
Circuit Theory ◽  
Closed Form Expression ◽  
Simple Circuit ◽  
Form Expression ◽  
Coupled Line ◽  
Interdigital Capacitor ◽  
Quarter Wavelength ◽  
Coupled Lines ◽  
Good Agreement

A new model for the microstrip line interdigital capacitor is proposed. This model consists of calculating the2N×2N Y-matrix of theNcoupled lines using the multiple coupled line tool. Then, this matrix is reduced to a2×2matrix using simple circuit theory. The capacitance at the end of each finger is taken into consideration using closed-form expression of the coplanar waveguide open-end capacitance. This model can predict the resonances that might appear around the quarter-wavelength frequency. These resonances are caused by the coupling between the fingers and exist only in capacitors with four fingers or more. Very good agreement is obtained between the results of our model and those obtained using the software HFSS and measurements.

Dislocation structures around SiO2 Particles in aged Cu-Cr-SiO2

1978 ◽  
Vol 36 (1) ◽  
pp. 594-595
Author(s):  
N.J. Long ◽  
M.H. Loretto ◽  
C.H. Lloyd
Keyword(s):  
Flow Stress ◽  
Single Crystals ◽  
Room Temperature ◽  
Thin Foil ◽  
Age Hardening ◽  
Dispersion Strengthening ◽  
Accurate Picture ◽  
The Matrix ◽  
Very High ◽  
Good Agreement

IntroductionThere have been several t.e.m. studies (1,2,3,4) of the dislocation arrangements in the matrix and around the particles in dispersion strengthened single crystals deformed in single slip. Good agreement has been obtained in general between the observed structures and the various theories for the flow stress and work hardening of this class of alloy. There has been though some difficulty in obtaining an accurate picture of these arrangements in the case when the obstacles are large (of the order of several 1000's Å). This is due to both the physical loss of dislocations from the thin foil in its preparation and to rearrangement of the structure on unloading and standing at room temperature under the influence of the very high localised stresses in the vicinity of the particles (2,3).This contribution presents part of a study of the Cu-Cr-SiO2 system where age hardening from the Cu-Cr and dispersion strengthening from Cu-Sio2 is combined.

Sign in / Sign up

Export Citation Format

Share Document