Microstrip dual-band dual-path bandpass filter (original) (raw)
A dual-band microstrip filter topology based on quarter-wavelength coupled-lines inter-connections
2013 IEEE International RF and Microwave Conference (RFM), 2013
A dual-band bandpass filter topology based on coupled-lines is presented. In the topology, two identical coupledlines are cascaded in series and duplicated in parallel. There are then ended with another two identical coupled-lines. The dualpath structure exhibits a 2 nd order dual-band response with three transmission zeros that separate the passbands from each other, and from the rejection band. The odd-and even-mode impedances of the coupled-lines control the bandwidth, passband and out-of-band responses of the dual-band filter. Finally, to verify the concept, a prototype of a dual-band bandpass filter is designed using EM simulator, fabricated on 1.6-mm-thick FR-4 substrate and measured. The resonant frequencies of the two passbands are centered at 1.82 GHz and 2.38 GHz.
A Compact Dual-Band Bandpass Filter Using Coupled Microstrip Lines
Iete Journal of Research, 2022
A quad-mode resonator is proposed for novel design of dual-band bandpass filters (DBBPFs) with good selectivity and compact size. The symmetrical resonator consists of a pair of coupled line sections (CLSs) and a transmission line section (TLS). Odd-/even-mode method is used to clarify the mode characteristics. Four excited resonant modes are applied to produce two passbands. The frequency ratio range can be adjusted by the CLSs, and the bandwidths can be controlled by the TLS. After installing a pair of U-shape coupling arms, a DBBPF with five transmission zeros (s) around the two passbands are designed and fabricated. The measured results are in good agreement with the simulated results, demonstrating that the proposed filter is feasible in practical use.
Compact dual-band bandpass filter using coupled three-line microstrip structure with open stubs
2011 4th IEEE International Symposium on Microwave, Antenna, Propagation and EMC Technologies for Wireless Communications, 2011
A quad-mode resonator is proposed for novel design of dual-band bandpass filters (DBBPFs) with good selectivity and compact size. The symmetrical resonator consists of a pair of coupled line sections (CLSs) and a transmission line section (TLS). Odd-/even-mode method is used to clarify the mode characteristics. Four excited resonant modes are applied to produce two passbands. The frequency ratio range can be adjusted by the CLSs, and the bandwidths can be controlled by the TLS. After installing a pair of U-shape coupling arms, a DBBPF with five transmission zeros (s) around the two passbands are designed and fabricated. The measured results are in good agreement with the simulated results, demonstrating that the proposed filter is feasible in practical use.
2020
Background and Objectives: Due to the rapid development in wireless communications, bandpass filters have become key components in modern communication systems. Among the microwave filter technologies, planar structures of microstrip line are chosen, due to low profile, weight, ease of fabrication, and manufacturing cost. Methods: This paper designs and simulates a new microstrip dual-band bandpass filter. In the proposed structure, three coupled lines and a loaded asymmetric two coupled line are used. The design method is based on introducing and generating the transmission zeros in the frequency response of a wideband single-band filter. A wideband frequency response is obtained using the three coupled lines, and the transmission zeros are achieved using the novel loaded asymmetric two coupled lines. Results: The proposed dual-band filter is designed and simulated on a Rogers RO3210 substrate for WLAN applications. Dimension of the proposed filter is 11.22 mm × 13.04 mm. The electromagnetic (EM) simulation is carried out by Momentum EM (ADS) software. Simulation results show that the proposed dual-band bandpass filter has two pass-bands at 2.4 GHz and 5.15 GHz with a loss of less than 1 dB for two pass-bands. Conclusion: Among the advantages of this filter, low loss, small size, and high attenuation between the two pass-bands can be mentioned.
A dual-band bandpass filter with wide and highly attenuated stopbands is designed using parallel coupled microstrip line (PCML) and stepped-impedance-resonators (SIRs). The proposed filter is composed of a pair of highly coupled PCML-SIR structure and a central resonator using a low impedance rectangular microstrip. Initially, the wide dual-band performance is achieved by creating a transmission zero between those two bands using a tightly coupled PCML-SIR with a suitable impedance ratio. Then, a low impedance resonator is placed between the pair of PCML-SIR to generate multiple resonant frequencies for a broadband performance. The simulated and measured results of those filters agree very well. The bandwidth of the first band in the developed filters extends from 1.75 GHz to 3.75 GHz with less than 0.3 dB insertion loss at the center of the band. The second band has a bandwidth that extends from 6.95 GHz to 8.75 GHz with less than 0.5 dB insertion loss at the center of that band. The stopband separating those two passband has more than 30 dB attenuation with transmission zero at 5.85 GHz.
A Novel Microstrip Dual-band Bandpass Filter Using Dual-Mode Square Patch Resonators
Dual-mode square patch resonator is well known in the design of a single band quasi-elliptic bandpass filter response. Here, the dual-mode square patch resonator is employed to achieve a dualband bandpass filter. A 6 pole dual-band bandpass filter response with 3 poles at each passband will be presented. The dual-band filter also exhibits a transmission zero between the two passbands. A detailed discussion on the design procedure together with the simulation and experimental results will be presented.
Design of High Performance Microstrip Dual-Band Bandpass Filter
Radioengineering, 2015
This paper presents a new design of dual-band bandpass filters using coupled stepped-impedance resonators for wireless systems. This architecture uses multiple couple stubs to tune the passband frequencies and the filter characteristics are improved using defected ground structure (DGS) technique. Measurement results show insertion losses of 0.93 dB and 1.13 dB for the central frequencies of 2.35 GHz and 3.61 GHz, respectively. This filter is designed, fabricated and measured and the results of the simulation and measurement are in good agreement.
A dual-mode dual-band bandpass filter using a single ring resonator
2009
A dual-mode dual-band bandpass filter is designed using a single stub-loaded slot ring resonator. This resonator is coupled to the two external feed lines at two positions spaced at 135 • along the slot ring through a pair of microstrip-slotline T-junctions. With a proper choice of the degree of external coupling, the first-order degenerate modes are split to make up the first passband with two transmission poles. The second passband is realized by the second-order degenerate modes, which are stimulated by symmetrically attaching four identical stubs along the slotring. The center frequency ratio of the two operating passbands is controlled by the nature and strength of the external coupling, which is determined by the characteristics of the microstrip open-circuited stubs. Finally, a dualband filter with center frequencies at 2.4 and 5.2 GHz is designed and fabricated. Measured results verify the design principle and predicted dual-passband performance. Benefiting from an additional transmission zero brought by the transitions,the upper stopband is expanded up to 12.75 GHz with at least 13 dB of rejection.
International Journal of Microwave and Wireless Technologies, 2011
In this paper a dual-band bandpass filter with sharp rejection is proposed. The filter is realized by using two half-wavelength stepped impedance resonators to operate at the passbands 2.5 and 3.5 GHz. To increase the band width further to about 45 MHz at the lower passband and 115 MHz at the higher passband, interdigital capacitors are introduced between resonator and input and output combining network. Measured insertion loss is about 1.45 and 1.7 dB at first and second passbands, respectively. A finite transmission zero in between two passbands at 2.84 GHz is realized to improve the selectivity of the filter. The design procedure to get highly selective response of the proposed filter is explicitly explained. An equivalent circuit model of proposed filter is developed that matches well with measured results.
A Novel Dual-Mode Wideband Band Pass Filter
─ A novel Wideband (WB) Bandpass Filter (BPF) with improved passband performance using a Defected Ground Structure (DGS) is presented in this paper. The proposed BPF is composed of two novel basic WB resonators and six Dumbbell-Shaped (DS) DGSs. By cascading resonators we can achieve better skirt characteristics, and by using DS-DGSs under interdigital coupled I/O lines we can improve the return loss within the passband. The simulated and measured results are found in good agreement with each other showing a wide passband from 4.93 to 11.62 GHz, a wide upper stopband with around 25 dB attenuation up to 20 GHz, and sharp roll-offs around 0.03 in lower and upper edges.
New Dual-Mode Ring Bandpass Filter Using Symmetrical Left-Handed Transmission Line
2007 Asia-Pacific Microwave Conference, 2007
ABSTRACT This paper presents a new dual-mode microstrip ring bandpass filter (BPF) based on the left-handed transmission line (LH-TL). To achieve dual-mode response, a high impedance LH-TL can easily be realized to perturb a pair of degenerate modes, which difficulty is realized in the conventional dual-mode ring filter. The proposed BPF is designed and fabricated on an FR-4 substrate to suit the 2.45 GHz ISM band application with a fractional bandwidth of 16.2 percentages. Across the bandwidth, the measured insertion loss is less than 1.5 dB, whereas the input and output return losses are better than 20 dB from 2.37 to 2.59 GHz. The measured results are in good agreement with the simulated results.
Design and Analysis of a Wide Stopband Microstrip Dual-band Bandpass Filter
ARO-THE SCIENTIFIC JOURNAL OF KOYA UNIVERSITY, 2021
A novel configuration of a dual-band bandpass filter (DB-BPF) working as a harmonic attenuator is introduced and fabricated. The proposed filter operates at 3 GHz, for ultrahigh-frequency and super high-frequency applications, and 6.3 GHz, for wireless applications. The presented layout has a symmetric structure, which consists of coupled resonators. The designing of the proposed resonator is performed by introducing a new LC equivalent model of coupled lines. To verify the LC model of the coupled lines, the lumped elements are calculated. The introduced filter has a wide stopband up to 85 GHz with 28 th harmonic suppression, for the first channel, and 13 th harmonic suppression, for the second channel. The harmonics are attenuated using a novel structure. Furthermore, the proposed BPF has a compact size of 0.056 λ g 2. Having several transmission zeros that improve the performance of the presented BPF are another feature. The proposed DB-BPF is fabricated and measured to verify the design method, where the measurement results confirm the simulations.
Dual-band dual-mode bandpass filter using seriescoupled ring resonators
2012 IEEE Asia-Pacific Conference on Applied Electromagnetics, APACE 2012 - Proceedings, 2012
This paper proposed a dual-band ring filter using two identical microstrip dual-mode ring resonators. The rings are cascaded in series side-by-side via a single quarter wavelength coupled-line forming two transmission poles which are distributed in each passband. Meanwhile, the coupled-line positioned in between the two rings help to create the center transmission zero which can be used to control the rejection level of the in-between isolation. The characteristics of the dual-band filter in terms of bandwidth, passband and out-of-band responses are controlled by the line impedances of the rings and the oddand even-mode impedances of the coupled-line. Finally, to verify the concept, a prototype of a dual-band dual-mode filter is designed using EM simulator, fabricated on 1.63-mm-thick Tachonic substrate and measured. The resonant frequencies of the two passbands are found at 1.73 GHz and 2.37 GHz while the center transmission zero is found at 2.04 GHz.
DESIGN OF NOVEL DUAL-BAND BANDPASS FILTER WITH MICROSTRIP MEANDER-LOOP RESONATOR AND CSRR DGS
Progress in Electromagnetics Research-pier, 2008
A novel dual-band bandpass filter with meander-loop resonator and complement split-ring resonator (CSRR) defected ground structure (DGS) is proposed in this letter. Microstrip meanderloop resonator and CSRR DGS are operated for respective passbands. Several finite attenuation poles in stopbands are realized to improve the selectivity of the proposed bandpass filter and isolation between the two passbands. Compact size, dual band and high selectivity characteristics are realized by this type of filter structure. The filter is evaluated by experiment and simulation with very good agreement.
An Enhanced Miniature Dual-Mode, Band Microstrip Bandpass Filter Based Single CSRR
2020
Article history: Received 29 October 2019 Received in revised form 1 December 2019 Accepted 9 December 2019 Available online 10 December 2019 An Enhanced miniature dual-band dual-mode microstrip bandpass filter (BPF) based on Complementary Split Ring Resonator (CSRR) graved on the ground plane of selected microstrip structure was proposed. This project consisted of two components have been combined in one item, this item has acceptable characteristics in terms of size and output result. A dual band square loop resonator with a small patch designed at one corner to degenerate dual mode properties has been printed on the top layer of the utilized substrate. On the other hand, a complementary split ring resonator has been graved on the bottom layer of the referred substrate to enhance the results of suggested structure. The proposed microstrip filter was utilized for Industrial Scientific and Medical (ISM) applications (2.45 GHz) with -25 dB with twice transmission zeroes as a first ba...
A compact narrow-band microstrip bandpass filter with a complementary split-ring resonator
Microwave and Optical Technology Letters, 2006
location and transmission performances are similar to the filter proposed in the precious section. 5. EXPERIMENTAL RESULTS The proposed dual-mode bandpass filter is fabricated and its photograph is given in Figure 9. According to the smallest resolution of PCB manufacturing process, the dimensions of the spur-lines are adjusted. l 1 ϭ 0.3 mm, l 2 ϭ 0.4 mm, g 1 ϭ 0.2 mm are chosen in Figure 9. Figure 10 shows the simulated and measured results. The filer has a return loss better than Ϫ15 dB within 9.8-10.6 GHz and the insertion loss is less than 0.9 dB within 9.9-10.8 GHz. The maximum return loss in 44.6 dB at 10.6 GHz. The measurement was completed using Agilent 8720ES. 6. CONCLUSIONS New microstrip dual-mode triangular-patch bandpass filters with low insertion loss and one transmission zero are presented in this article. Without any perturbations on the surface of the patch resonator or orthogonal feed lines, the degenerate modes can be excited by the use of the input/output microstrip lines with spurlines. It has been verified by simulation and measurement. In addition, the proposed filter is compact, simple, and attractive in modern communication applications.
Dual-Mode Dual-Band Bandpass Filter with Asymmetrical Transmission Zeros
Progress In Electromagnetics Research M, 2019
This paper presents a high-selectivity dual-mode dual-band bandpass filter with good cutoff signal rejection. The high-selectivity dual-mode dual-band bandpass filter is designed by an asymmetrical transmission zero (TZ). The asymmetrical transmission zeros next to the upper sideband of the first resonant filter and the TZ at the lower sideband of the second passband filter are combined to form a dual-mode dual-band filter. The locations of the TZ are designed at the side passbands of the filters in order to filter out unwanted signals, obtain good cutoff rate in the stopband, and give much improved signal selectivity for the dual-band bandpass filter. One dual-mode filter is designed at the center frequency of 1.8 GHz and the other's desired performance at 2.4 GHz. The two filters can be combined using the coupled feed lines in which these coupled feed lines present a simple structure of dualmode dual-band bandpass filter. The insertion loss of the dual-mode dual-band bandpass filter is less than 1.2 dB, and the rejection between two transmission bands is about 18 dB from 1.9 to 2.35 GHz. This high-performance dual-mode dual-band bandpass filter can be used in many wireless communication systems. 1. INTRODUCTION Nowadays, filter is an important and essential component in the RF front ends of both the receiver and transmitter in modern wireless and mobile communication systems. It can be designed and fabricated on various materials. Particularly, popular filter structures are planar filters because they can be fabricated using printed circuit technology and are suitable for commercial applications due to their compact size, light weight, and low-cost integration [1]. In modern multi-service and multi-band communication systems, multiband bandpass filter (BPF) is an important and essential component in the RF/microwave front ends of both the receiver and transmitter. Dual-band filters have been proposed and exploited extensively as a key circuit block in dual-band wireless communication systems [2-7]. Recently, various design approaches have been reported to develop dual-band BPFs for multi-band communication systems [8-13]. However, due to limited degrees of freedom in design parameters, the design of dual-band BPFs is still challenging to the designers [14]. Based on the single-mode open-loop resonator such as in [15, 16] this single-mode resonator structure focuses only on the odd mode resonance. Although an even mode resonance is present, this is approximately at twice the fundamental resonant frequency and therefore is of little use in single band filter synthesis. Consequently, the even mode will appear as the first spurious harmonic, which degrades the filter response. Dual-mode filters also make use of the even-mode and therefore behave as a doubly tuned circuit. These filters are not only more compact but also offer significantly less insertion loss [17, 18].
Journal of Telecommunication, Electronic and Computer Engineering, 2017
This paper presented a design to realize a compact dual-band bandpass filter using a pair of coupled symmetric stepped impedance resonator (SIRs) and U-shaped microstrip structure for wireless communication applications. To obtain its compact size, the symmetric SIR was bent like an L-shape. The U-shaped microstrip structure was designed and integrated into the SIR to achieve notch bandstop response so as to produce the specified dual-band bandpass filter. For the resonant frequency and attenuation, the U-shaped microstrip structure was designed at 3GHz and greater than 60dB respectively. Based on the simulation and experimental results, it was verified that this proposed design produced two passbands centered at 2.5GHz and 3.5GHz with the fractional bandwidth of more than 16%. The return loss and insertion loss are better than 15dB and 1dB respectively. The simulated and measured results are both presented and showed a good agreement. This proposed dualband bandpass filter is benef...
Combination of a one-wavelength ring and coupled-lines for compact and selective bandpass filter
Wireless Technology and Applications (ISWTA), 2012 IEEE Symposium on, 2012
This paper presents a wideband bandpass filter topology which is based on a combination of a one-wavelength ring and two identical quarter-wavelength coupled-lines. The 3rd order bandpass response can be controlled by varying the line impedance of the ring and the even-and odd-mode impedances of the coupled lines. A simplified equivalent circuit diagram of the topology is also proposed to open for further analysis of the filter. A realization of the filter is performed using microstrip technology on FR4 epoxy glass substrate and the measurement results are found to be in good agreement with the simulation results.
Investigation of dual-mode microstrip bandpass filter based on SIR technique
PLoS ONE, 2016
In this paper, a new bandpass filter design has been presented using simple topology of stepped impedance square loop resonator. The proposed bandpass filter has been simulated and fabricated using a substrate with an insulation constant of 10.8, thickness of 1.27mm and loss tangent of 0.0023 at center frequency of 5.8 GHz. The simulation results have been evaluated using Sonnet simulator that is extensively adopted in microwave analysis and implementation. The output frequency results demonstrated that the proposed filter has high-quality frequency responses in addition to isolated second harmonic frequency. Besides, this filter has very small surface area and perceptible narrow band response features that represent the conditions of recent wireless communication systems. Various filter specifications have been compared with different magnitudes of perturbation element dimension. Furthermore, phase scattering response and current intensity distribution of the proposed filter have been discussed. The simulated and experimental results are well-matched. Lastly, the features of the proposed filter have been compared with other designed microstrip filters in the literature. © 2016 Mezaal, Ali.This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.