Design Of Ultra-wideband Bandpass Filter Research Articles

An On-Chip Ultra-Wideband Bandpass Filter in 0.18-μm SiGe BiCMOS Technology

This letter presents an on-chip ultra-wideband (UWB) bandpass filter (BPF) in 0.18- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> SiGe BiCMOS Process. The proposed UWB BPF is constituted by cascaded quasi-elliptic response high-pass filter (HPF) and low-pass filter (LPF). A series <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">LC</i> circuit is introduced in the classical fifth-order lumped-element HPF, so that a transmission zero (TZ) is generated to form quasi-elliptic response. The microstrip line LPF with two series of open stubs can generate another two TZs, which also result in quasi-elliptic response. Step-to-step design procedure is given to guide the UWB BPF design. The measured result shows that the fabricated UWB BPF covers the frequency range of 10 – 50 GHz with the in-band return loss better than 13.5 dB, and the minimum in-band insertion loss is 1.99 dB. The core size of fabricated UWB BPF is 382 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu \text{m}\,\,\times 428\,\,\mu \text{m}$ </tex-math></inline-formula> excluding testing pads.

Wide stopband single layerquasi‐elliptic ultra‐widebandbandpass filter

This paper presents the design of a microstrip ultra-wideband (UWB) bandpass filter that exhibits desirable characteristics of low-loss, high selectivity, wide stopband and high out-of-band rejection at room temperature. These characteristics are normally achieved with high temperature superconductor filters that require cryogenic cooling. The design of the proposed filter was realized by exciting multiple resonant modes in a unique Z-shaped microstrip resonator. The admittance of the filter configuration can be tuned prior to fabrication to adjust its center frequency by about 11.5% without affecting the profile of the bandpass response however this can have an impact of the loss. The proposed configuration allows adjustment of the upper and lower transmission zeros defining the bandpass response by 20.5% and 11.4%, respectively, without degrading the overall filter response. The low-loss quasi-elliptic function UWB bandpass filter design was fabricated on a commercially available dielectric substrate using standard PCB technology and its performance verified. The fabricated filter exhibits insertion-loss of 0.68 dB and return-loss better than 17 dB.

Two Decades of UWB Filter Technology: Advances and Emerging Challenges in the Design of UWB Bandpass Filters

The past two decades have witnessed an unprecedented growth in the study and implementation of different short-range wireless services. However, the deployment of multiple short-range communication techniques has led to an overpopulation of the radio spectrum. Ultrawide-band (UWB) technology aims to offer an alternative to this spectrum scarcity as it can coexist with other radio technologies [Bluetooth, Worldwide Interoperability for Microwave Access (WiMAX), and Wireless Local Area Network (WLAN)] while causing minimal interference. The prospects of UWB technology allowing high data rate (up to 500 Mb/s) with low power consumption (<;0.5 mW) up to a typical range of 10 m have escalated their demands over other short-range communication systems.

A 10–50-GHz UWB BPF With GSG Probe Transition Using Micromachined Rectangular Microcoaxial Line

This article presents a millimeter-wave (mmW) ultrawideband (UWB) bandpass filter (BPF) using micromachined rectangular microcoaxial line ( \textRμCL). The tightly coupled stepped-impedance stub loaded resonator (TC-SISLR) exhibiting multiple-mode resonator (MMR) property, which has nine controllable transmission poles (TPs) and two controllable transmission zeros (TZs), is proposed to achieve the design goal. Nine controllable TPs of TC-SISLR can support a 10-50-GHz UWB passband, while two controllable TZs of TC-SISLR can provide a sharp rejection passband. Step-to-step design process is given to guide the 10-50-GHz UWB BPF design, and the vertical broadside coupling configuration and the defected ground structure (DGS) are introduced to strengthen the tight coupling. Moreover, the \textRμCL-to-ground-signal-ground (GSG) probe transition is also proposed and designed for on-chip measurement. As examples, the back-to-back GSG probe transition is fabricated, which has a low loss of 0.19 dB within 10-50-GHz passband, and a low loss of 0.6 dB up to 110 GHz. A 10-50-GHz UWB BPF with GSG probe transition is also fabricated, which has a minimum insertion loss of 0.44 dB within 10-50-GHz passband.

Uwb Bpf using Quad Section Stepped Impedance Resonator

Ultra wide band (UWB) frequency range is from 3.1 to 10.6 GHz with a bandwidth of 7.5 GHz. UWB bandpass filter(BPF) is an essential component of any UWB communication system. Design of UWB BPF with extremely high bandwidth is a challenge task. In this paper a simple method is developed for the design of UWB BPF. A quad section stepped impedance resonator (QSSIR) is used as the basic element of the filter. QSSIR has four impedance sections connected in cascade. Ultra wide bandwidth is realized by appropriately selecting impedance ratio and electrical length ratio of the SIR. Two transmission zeros are introduced in the insertion loss response by folding the QSSIR. Designed filter has bandwidth extending from 3.73 to 9.93 GHz with a fractional band width (FBW) of 91% and center frequency 6.83 GHz. There are five transmission poles in the obtained frequency response. Simulation is performed using ANSOFT HFSS. Designed filter was fabricated using FR4 substrate. Test results are found to be in good agreement with simulations. Proposed filter has a simple planar structure. Fabrication is easy. It can be used in UWB systems as band pass filter

Design of UWB Bandpass Filter with Notched Band Using Distributed CRLH Transmission Lines

This study presents an Ultra-Wideband (UWB) filter with a notched band. The filter adopts novel Composite Right/Left-Handed (CRLH) Transmission Lines (TLs), the unit cell of which is theoretically analyzed to derive the design formulas. A model of the CRLH TLs is composed with distributed elements rather than lumped elements. Based on the results of the analysis, it is confirmed that the proposed structures are CRLH TLs. A UWB bandpass filter with a notched band is designed and fabricated using the induced formulas. The measurement results show that the fabricated UWB bandpass filter has an insertion loss of less than 3 dB, a bandwidth of 2.8-10.5 GHz and a rejection of greater than 27 dB at 5.75 GHz.

Synthesis design of UWB bandpass filter using multiple resonance resonator (MRR)

An ultra-wideband (UWB) bandpass filter synthesis and design, using a multiple resonance resonator (MRR), is presented. Mixed-mode coupling is used to introduce a finite transmission zero to increase the filter selectivity. The equivalent circuit of the design is used to find the filtering function using even–odd mode analysis. The synthesis procedure is done on an extracted filtering function in order to realise the quasi-Chebyshev filtering response. Finally, a compact filter prototype has been fabricated to validate the synthesis theory and simulated design. The measured and simulated results show good agreement.

Compact tri-notched ultrawideband bandpass filter design using CSRR, DGS, and FMRR configurations

The folded multiple-mode resonators with complementary split ring resonator (CSRR), and defected ground structures (DGS) are introduced for notched ultrawideband (UWB) bandpass filter (BPF) design in this article. Using the CSRR, FMRR, notched wide-band BPF, a notch response can exist in the UWB passband for blocking the interference. Adjusting the size factor of CSRR, the wide tuning ranges of notch frequencies included the desired frequencies of 5.2/5.8 GHz are achieved. The lower insertion loss (0.31 dB), higher rejection level (−48.40 dB), wider bandwidth (FBW 75%), and wider stopband (extended to 2.01 f0 below −20 dB rejection level) of UWB band at the central frequency f0 = 4.58 GHz are obtained. Second, design a CSRR, DGS, FMRR, tri-notched UWB filter, the wider bandwidth (3.1–9.8 GHz) with FBW = 126%, lower insertion loss (0.26 dB), and higher rejection level (−44 dB) of UWB band at central frequency f0 = 5.6 GHz are presented. Using the CSRR and interdigital couple, three notch responses can exist in the UWB passband for blocking the interference signals. Adjusting the size factor of CSRR and interdigital couple, the wide tuning ranges of notch frequencies included the desired frequencies of 5.18/6.10/8.08 GHz are achieved. The wide tuning ranges of three notched frequencies cover from 5.0 to 8.4 GHz. It is a simple way to control the notch responses. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:571–579, 2014.

Tri-notched Ultra-wideband Bandpass Filter Design Using FMMR, CSRR, DGS and Inter-Digital Couples

A folded multiple-mode resonator (FMMR) with complementary split ring resonator (CSRR), defected ground structures (DGS) and inter-digital couple is introduced for ultra-wideband bandpass filter design in this paper. The wider bandwidth (3.1 to 9.8 GHz) with FBW = 126 %, lower insertion loss (0.26 dB), and higher rejection level (-44 dB) of UWB band at central frequency f0 = 5.6 GHz are presented. By using the CSRR and inter-digital couple, three notch responses can exist in the UWB passband for blocking the interference signals. Adjusting the size factor of CSRR and inter-digital couple, the wide tuning ranges of notch frequencies included the desired frequencies of 5.18/6.10/8.08 GHz are achieved. The wide tuning ranges of two notch frequencies cover from 5.0 GHz to 8.4 GHz. It is a simple way to control the notch response.

Design of Ultra-Wideband Bandpass Filters With Fixed and Reconfigurable Notch Bands Using Terminated Cross-Shaped Resonators

In this paper, a novel terminated cross-shaped resonator (TCSR) is analyzed and used to design ultra-wideband (UWB) bandpass filters (BPFs) with fixed and reconfigurable notch bands. It is found that the TCSR can exhibit a maximum three poles and two zeros when open and short terminations are applied. The intrinsic zero is simply used for the implementation of notch bands offering systematic design and flexible tuning capabilities. Bandwidth can also be kept unchanged when tuning a notch within the UWB passband. In contrast to common band-notched UWB BPFs using additional notch resonators, only a single TCSR is required to realize band-notched UWB filters. Three UWB BPF prototypes, including a four-pole filter with 94.7% fractional bandwidth (FBW) and a notch band at 5.8 GHz, a five-pole filter with 111% FBW and dual notch bands at 4.3/9.1 GHz, and a four-pole filter with 82.4% FBW and reconfigurable notch band from 4.6 to 6.5 GHz are designed and experimentally characterized. Their experimental characterizations are in good agreement with theoretical analysis validating a simple approach of band-notched UWB BPF design.

Compact Microstrip UWB Bandpass Filter With Dual Notched Bands Using E-Shaped Resonator

A new microstrip ultra-wideband (UWB) bandpass filter (BPF) with two sharp notches using E-shaped resonator is proposed in this letter. The circuit topology and its corresponding electrical parameters of the initial microstrip UWB BPF are achieved by a variation of genetic algorithm (GA). Then, the resonance properties of the E-shaped resonator are studied. Results reveal that the multiple-mode property of the E-shaped resonator can be utilized in the UWB BPF design to achieve dual band-notched performance. To validate the design concept, a microstrip UWB BPF with two notched bands respectively centered at frequencies of 5.9 GHz and 8.0 GHz is designed and fabricated. Both simulation and experimental results are provided with good agreement.

UWB bandpass filter with novel structure and super compact size

An ultra-wideband (UWB) bandpass filter (BPF) with a novel structure and super compact size is presented. This UWB BPF is designed based on a three-line coupled resonator (TLCR), which was used as feedlines in the past. The TLCR has the characteristics of simple structure and wide passband, thus it is very suitable for compact UWB BPF design. Then, four bent stubs are loaded to improve the performance of this filter. Both the simulated and measured results show that this filter has good performance and the size is miniaturised by more than 70% compared with most reported UWB BPFs.

Design of UWB bandpass filter with dual notched bands

An ultra-wideband (UWB) bandpass filter (BPF) with dual sharply rejected notch-bands to eliminate the interference from coexisting radio systems is presented in this paper. The characteristics of the proposed notched structure are investigated using simulations to demonstrate the design flexibility of the notchband performance. After integrating the proposed notched structure into the basic UWB BPF based on a stepped-impedance stub loaded resonator (SISLR), a UWB BPF with dual sharply rejected notched bands at 5.2 and 5.8 GHz is constructed. Finally, the designed filter is built and tested. The simulated and measured results are found to be in good agreement to verify the proposed design.

Compact microstrip ultra-wideband double/single notch-band band-pass filter based on wave's cancellation theory

A novel approach with a new configuration is introduced to design an ultra-wideband (UWB) band-pass filter (BPF) that demonstrates double/single notch-bands using micro-strip transmission lines without using any via-hole. The proposed approach is established using two parallel stepped-impedance resonators (SIR) that provide two paths with different electrical lengths. The mechanism of realising notch-bands within the pass-band of the UWB BPF is developed based on the waves’ cancellation theory. To realise single or double notch-bands (DNBs) within the pass-band of a UWB BPF, the conventional tri-section stepped-impedance resonator (TSSIR) is adopted and its fundamental and first spurious resonance frequencies are chosen either to be suppressed or supported. New parallel dual-section T-shaped and TSSIRs are proposed, optimised and fabricated to provide single and DNBss, respectively. The proposed concept avoids using via holes, which is conventionally used in notch filters. In addition, a size reduction of about 75% is reported in comparison with the conventional BPF with a single notch-band accompanied by two transmission zeroes at the lower and upper stop-bands. Moreover, our proposed DNBs BPF demonstrates a comparable performance while being smaller in size (up to a 12.6% size reduction) to that of the latest UWB BPF design that used complicated and expensive multilayer liquid crystal polymer (LCP) technology.

Application of Cross-Shaped Resonator to the Ultra Wideband Bandpass Filter Design

An ultra-wideband (UWB) bandpass filter (BPF) with two cascaded cross-shaped resonators is proposed and implemented. As the starting work of this letter, a cross-shaped resonator with wide passband is introduced. With the use of even- and odd-mode approach, this initial resonator is characterized and designed to build up a UWB BPF. And then, a cascaded UWB BPF is fabricated to satisfy Federal Communications Commission indoor mask.

Design of UWB Bandpass Filter Using Stepped-Impedance Stub-Loaded Resonator

In this letter, an ultra-wideband (UWB) bandpass filter (BPF) using stepped-impedance stub-loaded resonator (SISLR) is presented. Characterized by theoretical analysis, the proposed SISLR is found to have the advantage of providing more degrees of freedom to adjust the resonant frequencies. Besides, two transmission zeros can be created at both lower and upper sides of the passband. Benefiting from these features, a UWB BPF is then investigated by incorporating this SISLR and two aperture-backed interdigital coupled-lines. Finally, this filter is built and tested. The simulated and measured results are in good agreement with each other, showing good wideband filtering performance with sharp rejection skirts outside the passband.

Band-Notched UWB BPF Design Using Parasitic Coupled Line

A compact microstrip ultrawideband (UWB) bandpass filter (BPF) with a narrow notched band in the UWB passband is presented. The narrow notched band was introduced by using a new technique that involves embedding a parasitic coupled line to the UWB BPF in order to reject any undesired existing radio signal that may interfere with the determined UWB passband. The notched band can be easily generated and set at any desired frequency by varying the structural parameters of parasitic coupled line. The design is successfully realized in theory and verified by electromagnetic (EM) simulation and the experiment. This filter can be integrated in UWB radio systems and efficiently enhance the interference immunity from undesired signals such as wireless local area network (WLAN).

Synthesis Design of Ultra-Wideband Bandpass Filters With Composite Series and Shunt Stubs

This paper presents a direct synthesis procedure for efficient design of a class of ultra-wideband bandpass filters with composite series and shunt transmission-line stubs. The proposed single-stage bandpass prototype is formed by cascading two sets of series open-ended and shunt short-ended stubs through a multisection nonuniform transmission line. All the stubs are set with an identical electrical length, i.e., thetasc , at lower cutoff frequency fc and the middle connecting line is composed of stepped-impedance transmission line with i sections, and each section has an electrical length thetasc. The proposed filter topology aims to construct an ultra-wide bandpass filter with Chebyshev equal-ripple responses and (i + 3) in-band transmission poles. Based on the derivation of the transfer function, a synthesis approach is established and systematically described to design this type of filters according to the specifications such as lower/upper cutoff frequencies. Next, a multistage bandpass filter prototype is proposed and the synthesis design procedure is also presented. The implementation is achieved by using hybrid microstrip line and slotline sections. Compared with traditional stub filters, the proposed filters achieve higher order transmission zeros and thus provide higher selectivity. As design examples, two single-stage and one three-stage bandpass filters are designed and fabricated to confirm the theoretical predictions.

Band-notched ultra-wideband bandpass filter design using combined modified quarter-wavelength tri-section stepped-impedance resonator

This study presents a new band-notched ultra-wideband (UWB) bandpass filter (BPF) that is designed using a new structure-shared multi-mode resonator (MMR). The MMR is formed by combining two quarter-wavelength ( lambda /4) tri-section stepped-impedance resonators (TSSIRs) in a proper fashion to exhibit both lambda /4 and half-wavelength ( lambda /2) types of resonance. With the first two resonant frequencies of the inherent lambda /4 TSSIR, the first two of the parasitic lambda /2 SIR and the coupling peaks of the input/output interdigital parallel-coupled lines properly located in the UWB passband, a six-transmission-pole UWB BPF can be realised. In this filter design, besides obtaining a uniform in-band transmission response, a notched band centred around 5.5 GHz is created by embedding L-shaped open-end slots in the TSSIR and loading the TSSIR with closely coupled winding-type resonators (WTRs) to filter out the 5-GHz wireless local-area network radio signal interferences. In addition, spur-lines are embedded in the TSSIR to sharpen the passband skirts for selectivity improvement.

MMR-based Band-notched UWB Bandpass Filter Design

A new band-notched ultra-wideband (UWB) bandpass filter (BPF) with an improved upper stopband is designed using a multi-mode resonator (MMR). The MMR, being a modified version of a common tri-section stepped-impedance resonator (TSSIR), is split at its two open ends with the input/output feed lines sandwiched in between to form an interdigital parallel-coupled configuration that results in stronger coupling. In addition, an extended coupling length in the second section of the TSSIR is featured to provide further coupling and impedance-matching tuning. With such a design strategy, coupling gaps of no smaller than 0.1 mm was achieved to obtain the required UWB response. In this design, the first five resonant modes of the MMR and the coupling peaks of the input/output parallel-coupled lines are properly located in the UWB passband to achieve a uniform in-band transmission response. Also, the spur lines and open-circuited stubs are implemented in the MMR to create a 5-GHz notched band and to broaden the upper stopband, respectively. The designed UWB BPF, which being verified by measurement, shows a very good UWB performance. The measured in-band minimum insertion loss and maximum group delay variation except those in the notched band are 0.45 dB and 0.05 ns, respectively, and the upper-end −20-dB stopband bandwidth is about 5.35 GHz. The created notched band is centered at 5.69 GHz with a maximum insertion loss of 37.2 dB and a 3-dB notch bandwidth of 18%.