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Butterworth filter

About: Butterworth filter is a research topic. Over the lifetime, 6187 publications have been published within this topic receiving 69070 citations.


Papers
More filters
Journal ArticleDOI
TL;DR: The analysis established the relationship between the attenuation rates of the movement artifact and the sEMG signal as a function of the filter band pass, and a Butterworth filter with a corner frequency of 20 Hz and a slope of 12 dB/oct is recommended for general use.

937 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

Journal ArticleDOI
TL;DR: This paper presents a 3rd order low-pass continuous-time filter with 4 MHz cut-off frequency, integrated in a 3 μm CMOS process, based on the direct simulation of a doubly-terminated LC ladder using capacitors and fully-balanced, current-controlled transconductance amplifiers with extended linear range.
Abstract: A third-order elliptic low-pass continuous-time filter with a 4-MHz cutoff frequency, integrated in a 3- mu m p-well CMOS process, is presented. The design procedure is based on the direct simulation of a doubly terminated LC ladder filter by capacitors and fully balanced, current-controlled transconductance amplifiers with extended linear range. The on-chip automatic tuning circuit uses a phase-locked loop implemented with an 8.5-MHz controlled oscillator that matches a specific two-integrator loop of the filter. The complete circuit features 70-dB dynamic range (THD >

652 citations

Journal ArticleDOI
TL;DR: If the frequency responses of the original ( M + 1) -band filter and its complementary filter are properly masked and recombined, narrow transition-band filter can be obtained and this technique can be used to design sharp low-pass, high- pass, bandpass, and bandstop filters with arbitrary passband bandwidth.
Abstract: If each delay element of a linear phase low-pass digital filter is replaced by M delay elements, an (M + 1) -band filter is produced. The transition-width of this (M + 1) -band filter is 1/M that of the prototype low-pass filter. A complementary filter can be obtained by subtracting the output of the (M + 1) -band filter from a suitably delayed version of the input. The complementary filter is an (M + 1) -band filter whose passbands and stopbands are the stopbands and passbands, respectively, of the original (M + 1) -band filter. If the frequency responses of the original ( M + 1) -band filter and its complementary filter are properly masked and recombined, narrow transition-band filter can be obtained. This technique can be used to design sharp low-pass, high-pass, bandpass, and bandstop filters with arbitrary passband bandwidth.

488 citations

Journal ArticleDOI
TL;DR: In this paper, a dual-band filter consisting of a bandstop filter and a wide-band bandpass filter in a cascade connection is presented, wherein the transfer functions of both the bandpass filters and bandstop filters are expressed in the Z domain.
Abstract: A synthesizing method is presented to design and implement digital dual-band filters in the microwave frequency range. A dual-band filter consists of a bandstop filter and a wide-band bandpass filter in a cascade connection, wherein the transfer functions of both the bandpass filter and bandstop filter are expressed in the Z domain. The bandstop filter is implemented by using a coupled-serial-shunted line structure, while the wide-band bandpass filter is constructed by using a serial-shunted line configuration. In particular, the bandwidth of each passband of the dual-band filter is controllable by adjusting the characteristics of both the bandpass filter and bandstop filter. By neglecting the dispersion effect between microstrip lines of different widths over a wide bandwidth, a dual-band filter is realized in the form of microstrip lines and its frequency responses are measured to validate this method.

422 citations


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Performance
Metrics
No. of papers in the topic in previous years
YearPapers
202322
202282
202140
202059
201941
201864