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Passband

About: Passband is a research topic. Over the lifetime, 14563 publications have been published within this topic receiving 170583 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: In this article, a method of coupling of modes in time was proposed to simplify both the analysis and filter synthesis aspects of these devices, and the response of filters comprised of an arbitrarily large dumber of resonators may be written down by inspection, as a continued fraction.
Abstract: Microring resonators side coupled to signal waveguides provide compact, narrow band, and large free spectral range optical channel dropping filters. Higher order filters with improved passband characteristics and larger out-of-band signal rejection are realized through the coupling of multiple rings. The analysis of these devices is approached by the novel method of coupling of modes in time. The response of filters comprised of an arbitrarily large dumber of resonators may be written down by inspection, as a continued fraction. This approach simplifies both the analysis and filter synthesis aspects of these devices.

1,733 citations

Journal ArticleDOI
TL;DR: In this article, a microstrip-line ultra-wideband (UWB) bandpass filter is proposed and implemented using a multiplemode resonator (MMR), aiming at transmitting the signals in the whole UWB passband of 3.1-10.6GHz.
Abstract: A novel microstrip-line ultra-wideband (UWB) bandpass filter is proposed and implemented using a multiple-mode resonator (MMR), aiming at transmitting the signals in the whole UWB passband of 3.1-10.6GHz. In the design, the first three resonant frequencies of this MMR are properly adjusted to be placed quasiequally within the UWB. Then, the parallel-coupled lines at the two sides are longitudinally stretched so as to raise the frequency-dispersive coupling degree with the coupling peak near the center of the UWB. After optimization of this filter, a good UWB bandpass behavior with five transmission poles is theoretically realized and experimentally confirmed. Within the whole UWB passband, the return loss is found higher than 10dB, and the group delay variation is less than 0.23ns.

990 citations

Journal ArticleDOI
TL;DR: In this article, a cross-coupled planar microwave filter using coupled microstrip square open-loop resonators is proposed, and a method for the rigorous calculation of the coupling coefficients of three basic coupling structures encountered in this type of filter is developed.
Abstract: A new type of cross-coupled planar microwave filter using coupled microstrip square open-loop resonators is proposed. A method for the rigorous calculation of the coupling coefficients of three basic coupling structures encountered in this type of filter is developed. Simple empirical models are derived for estimation of the coupling coefficients. Experiments are performed to verify the theory. A four-pole elliptic function filter of this type is designed and fabricated. Both the theoretical and experimental performance is presented.

874 citations

Journal ArticleDOI
TL;DR: In this article, the photonic bandgap (PBG) structure for microwave integrated circuits is presented, which is a two-dimensional square lattice with each element consisting of a metal pad and four connecting branches.
Abstract: This paper presents a novel photonic bandgap (PBG) structure for microwave integrated circuits. This new PBG structure is a two-dimensional square lattice with each element consisting of a metal pad and four connecting branches. Experimental results of a microstrip on a substrate with the PEG ground plane displays a broad stopband, as predicted by finite-difference time-domain simulations. Due to the slow-wave effect generated by this unique structure, the period of the PBG lattice is only 0.1/spl lambda//sub 0/ at the cutoff frequency, resulting in the most compact PEG lattice ever achieved. In the passband, the measured slow-wave factor (/spl beta//k/sub 0/) is 1.2-2.4 times higher and insertion loss is at the same level compared to a conventional 50-/spl Omega/ line. This uniplanar compact PBG (UC-PBG) structure can be built using standard planar fabrication techniques without any modification. Several application examples have also been demonstrated, including a nonleaky conductor-backed coplanar waveguide and a compact spurious-free bandpass filter. This UC-PBG structure should find wide applications for high-performance and compact circuit components in microwave and millimeter-wave integrated circuits.

831 citations

Proceedings ArticleDOI
James D. Johnston1
09 Apr 1980
TL;DR: This paper discusses a family of filters that have been designed for Quadrature Mirror Filter (QMF) Banks that provide a significant improvement over conventional optimal equiripple and window designs when used in QMF banks.
Abstract: This paper discusses a family of filters that have been designed for Quadrature Mirror Filter (QMF) Banks. These filters provide a significant improvement over conventional optimal equiripple and window designs when used in QMF banks. The performance criterion for these filters differ from those usually used for filter design in a way which makes the usual filter design techniques difficult to apply. Two filters are actually designed simultaneously, with constraints on the stop band rejection, transition band width, and pass and transition band performance of the QMF filter structure made from those filters. Unlike most filter design problems, the behavior of the transition band is constrained, which places unusual requirements on the design algorithm. The requirement that the overall passband behavior of the QMF bank be constrained (which is a function of the passband and stop band behavior of the filter) also places very unusual requirements on the filter design. The filters were designed using a Hooke and Jeaves optimization routine with a Hanning window prototype. Theoretical results suggest that exactly flat frequency designs cannot be created for filter lengths greater than 2, however, using the discussed procedure, one can obtain QMF banks with as little as ±.0015dB ripple in their frequency response. Due to the nature of QMF filter applications, a small set of filters can be derived which will fit most applications.

724 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
20241
2023250
2022647
2021448
2020687
2019809