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Showing papers on "Bessel filter published in 2009"


Journal ArticleDOI
TL;DR: The Bessel filter, the newly introduced BL3 filter, and the Gaussian filter are the most suitable filter functions to be used in FSD, based on the modification of the Blackmann filter.
Abstract: Overlapped bands often appear in applications of infrared spectroscopy, for instance in the analysis of the amide I band of proteins. Fourier self-deconvolution (FSD) is a popular band-narrowing mathematical method, allowing for the resolution of overlapped bands. The filter function used in FSD plays a significant role in the factor by which the deconvolved bands are actually narrowed (the effective narrowing), as well as in the final signal-to-noise degradation induced by FSD. Moreover, the filter function determines, to a good extent, the band-shape of the deconvolved bands. For instance, the intensity of the harmful side-lobule oscillations that appear in over-deconvolution depends importantly on the filter function used. In the present paper we characterized the resulting band shape, effective narrowing, and signal-to-noise degradation in infra-, self-, and over-deconvolution conditions for several filter functions: Triangle, Bessel, Hanning, Gaussian, Sinc2, and Triangle2. We also introduced and characterized new filters based on the modification of the Blackmann filter. Our conclusion is that the Bessel filter (in infra-, self-, and mild over-deconvolution), the newly introduced BL3 filter (in self- and mild/moderate over-deconvolution), and the Gaussian filter (in moderate/strong over-deconvolution) are the most suitable filter functions to be used in FSD.

35 citations


Journal ArticleDOI
TL;DR: In this article, a two-stage pseudo-differential operational transconductance amplifier (OTA) and its application in low-frequency continuous time filters was presented. But the OTA was designed in a 0.18 μm, 0.45 V V T CMOS process and consumes only 28 μW of power.
Abstract: This paper presents the design of a two-stage pseudo-differential operational transconductance amplifier (OTA) and its application in low-frequency continuous time filters. The OTA was designed in a 0.18 μm, 0.45 V V T CMOS process. An improved bulk-mode common-mode feedback (CMFB) circuit has been designed which does not load the OTA compared to prior art. A self cascode load structure and partial positive feedback provide higher gain. The bulk terminals of all transistors have been biased to lower their threshold voltages (VT) and maximize signal swing. The OTA operates at a supply voltage of 0.5 V and consumes only 28 μW of power. Rail-to-rail input is made possible by using the transistor's bulk terminal as the input. For a load of 20 pF the OTA has a measured DC gain of 63 dB and a gain-bandwidth product of 570 kHz. To demonstrate the use of the OTA in practical circuits, three active RC filters were designed: a 10 kHz Butterworth filter, a 10 kHz Bessel filter, and a 2.5 kHz Tschebycheff filter.

34 citations


Journal ArticleDOI
TL;DR: It is shown that the generalized Bessel function can be evaluated, in a numerically stable way, by utilizing a recurrence relation and a normalization condition only, without having to compute any initial value.
Abstract: In the relativistic and the nonrelativistic theoretical treatment of moderate and high-power laser-matter interaction, the generalized Bessel function occurs naturally when a Schrodinger-Volkov and Dirac-Volkov solution is expanded into plane waves. For the evaluation of cross sections of quantum electrodynamic processes in a linearly polarized laser field, it is often necessary to evaluate large arrays of generalized Bessel functions, of arbitrary index but with fixed arguments. We show that the generalized Bessel function can be evaluated, in a numerically stable way, by utilizing a recurrence relation and a normalization condition only, without having to compute any initial value. We demonstrate the utility of the method by illustrating the quantum-classical correspondence of the Dirac-Volkov solutions via numerical calculations.

28 citations


Journal ArticleDOI
TL;DR: In this paper, the authors presented a method for computing the incomplete Bessel functions arising when Gaussian-type orbitals are used for systems periodic in one spatial dimension, with an accuracy of ± 1 × 10−10.
Abstract: Presented here are detailed methods for evaluating the incomplete Bessel functions arising when Gaussian-type orbitals are used for systems periodic in one spatial dimension. The scheme is designed to yield these incomplete Bessel functions with an absolute accuracy of ±1 × 10−10, for the range of integer orders 0 ≤ n ≤ 12 [a range sufficient for a basis whose members have angular momenta of up to three units (s, p, d, or f atomic functions)]. To reach this accuracy level within acceptable computation times, new rational approximations were developed to compute the special functions involved, namely, the exponential integral E1(x) and the modified Bessel functions K0(x) and K1(x), to absolute accuracy ±1 × 10−15. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2009

22 citations


Book ChapterDOI
Nizar Demni1
TL;DR: In this article, the semi-group density and the generalized Bessel function and the W-invariant generalized Hermite polynomials were derived for dihedral systems.
Abstract: We are interested in radial Dunkl processes associated with dihedral systems. We write down the semi-group density and as a by-product the generalized Bessel function and the W-invariant generalized Hermite polynomials. Then, a skew product decomposition, involving only independent Bessel processes, is given and the tail distribution of the first hitting time of boundary of the Weyl chamber is computed.

21 citations


Journal ArticleDOI
TL;DR: In this article, the authors examined some recent results of Bownik on density and connectivity of the wavelet frames and obtained an asymptotically tight approximation result for wavelet frame.
Abstract: We examine some recent results of Bownik on density and connectivity of the wavelet frames. We use orthogonality (strong disjointness) properties of frame and Bessel sequences, and also properties of Bessel multipliers (operators that map wavelet Bessel functions to wavelet Bessel functions). In addition we obtain an asymptotically tight approximation result for wavelet frames.

20 citations


Journal ArticleDOI
TL;DR: This paper focuses on the problem of delay-range-dependent L2–L∞ filter design for stochastic systems with time-varying delay, and a sufficient condition is formulated in terms of linear matrix inequalities (LMIs), which guarantees the existence of a linear filter.
Abstract: This paper focuses on the problem of delay-range-dependent L 2---L ? filter design for stochastic systems with time-varying delay. The time delay varies in an interval. A delay-range-dependent sufficient condition is formulated in terms of linear matrix inequalities (LMIs), which guarantees the existence of a linear filter. The proposed filter ensures that the filtering error system is stochastically asymptotically stable and that its L 2---L ? performance satisfies a prescribed level. The corresponding filter design is cast into a convex optimization problem which can be efficiently handled by using standard numerical algorithms. Finally, a numerical example is given to illustrate the effectiveness of the proposed method.

17 citations


Proceedings ArticleDOI
01 Dec 2009
TL;DR: This paper investigates in detail the performance of a 3rd-order Sinh CMOS 8Hz low-pass filter of Bessel approximation suitable for ECG processing and presents the transistorlevel synthesis of this filter.
Abstract: Hyperbolic sine (Sinh) CMOS filters are of inherent class-AB nature and offer high dynamic range at half the total capacitance value when compared against their pseudodifferential class-AB log-domain counterparts. This characteristic renders their theoretical and practical study valuable. Only a very limited number of CMOS Sinh filter topologies have been reported in the literature to date mostly due to the considerably increased mathematical complexity associated with their design. This paper presents the transistorlevel synthesis and investigates in detail the performance of a 3rd-order Sinh CMOS 8Hz low-pass filter of Bessel approximation suitable for ECG processing. The filter is based on recent progress made and has been designed in the commercially available 0.35µm AMS process. Its static power consumption amounts to 0.1µW while its dynamic range exceeds 110dBs. The new filter exhibits a flat group delay of less than 1% error up to 6Hz and good variability performance verified by means of Monte Carlo simulations. The suitability of the filter as part of an ECG front-end is confirmed by the processing of artificially generated ECG signals contaminated by various simulated noise sources and fed as signal inputs into the Cadence Design Framework.

14 citations


Journal ArticleDOI
TL;DR: Measured results from the 19nW, 8-200Hz, 940@mm^2 Bessel filter chip confirm the validity of the proposed approach, and the filter reported here is particularly useful for biomedical instruments such as portable ECG devices and Pulse-oximeters.

9 citations


Proceedings ArticleDOI
24 Nov 2009
TL;DR: This paper presents an investigation into the effect on the performance of an optical network based on OADM by changing different filters at the receiver side by calculating the average BER and analyzing the response of the filter and comparing the results with ideal filter in O ADM based environment.
Abstract: This paper present an investigation into the effect on the performance of an optical network based on OADM by changing different filters at the receiver side. The calculated average BER and with the help of eye diagrams analyze the response of the filter Bessel, Butterworth and chebyshev filter and compare the results of the three filters responses in OADM based environment. With the help of OADM network resources are efficiently used, provide protection to network and routing features for add and drop channel. For analyzing of a OADM based network four nodes have been designed transmitting at 10 Gbps data rate connected with four fiber span of 10 Km long of type non linear single mode fiber with average power per channel is −9dBm.

8 citations


01 Jan 2009
TL;DR: A new amplitude envelope equalizing filter for the spectral delay filter is proposed and the properties of structures utilizing feedback and/or time-varying filter coefficients are discussed.
Abstract: Arecentlyintroducedstructuretoimplementacontinuouslysmooth spectral delay, based on a cascade of first-order allpass filters and an equalizing filter, is described and the properties of this spectral delay filter are reviewed. A new amplitude envelope equalizing filter for the spectral delay filter is proposed and the properties of structures utilizing feedback and/or time-varying filter coefficients are discussed. In addition, the stability conditions for the feedback and the time-varying structures are derived. A spectral delay filter can be used for synthesizing chirp-like sounds or for modifying the timbre of arbitrary audio signals. Sound examples on the use of the spectral delay filters utilizing the structures discussed in this paper can be found at http://www.acoustics.hut. fi/publications/papers/dafx09-sdf/.

Patent
01 Jul 2009
TL;DR: In this paper, a high speed sensor data transfer interface is described, which combines a bridge circuit, carrier voltage source, first order RC high pass filter, reference power supply, Bessel filter, and high speed analog to digital converter on a single Smart Transducer Interface Module board (STIM) to receive data from sensors.
Abstract: A high speed sensor data transfer interface is described. The interface combines a bridge circuit, carrier voltage source, first order RC high pass filter, reference power supply, Bessel filter, and high-speed analog to digital converter on a single Smart Transducer Interface Module board (STIM) to receive data from sensors. Data from the STIM is transferred to a Network Capable Application Processor (NCAP) having a microprocessor and either a Field Programmable Gate Array or a Complex Programmable Logic Device. The NCAP transfers data to a data exchange network.

Proceedings ArticleDOI
24 May 2009
TL;DR: A seventh order Bessel filter is realized using the proposed technique in a 0.18µm CMOS process and exhibits an undershoot of 1.3% and provides a stopband attenuation of 37 dB.
Abstract: Compact passive LC ladder lowpass filters for pulse shaping are realized using a single inductor with multiple taps. Mutual coupling between different inductors in a ladder results in zeros on the real and imaginary axis and can cause an undershoot in the step response and reduced attenuation in the stopband. Techniques to mitigate these effects are described. A seventh order Bessel filter is realized using the proposed technique in a 0.18µm CMOS process. This filter exhibits an undershoot of 1.3% and provides a stopband attenuation of 37 dB. It occupies 0.048 mm2, which is at least 15% smaller than a realization with separate spirals for each inductor.

Patent
24 Dec 2009
TL;DR: In this article, the authors proposed a method to prevent a waveform distortion from being generated, and outputting versine waveforms having various chord lengths in real-time using a Bessel filter.
Abstract: PROBLEM TO BE SOLVED: To provide a track deviation inspecting/measuring technology for preventing a waveform distortion from being generated, and outputting versine waveforms having various chord lengths in real time. SOLUTION: When a vehicle horizontal location as the path deviation quantity is calculated by a second order integration of a vehicle horizontal acceleration, a gain and a cutoff frequency of a Bessel filter are adjusted in response to a vehicle running speed. A waveform distortion is prevented from being generated since the Bessel filer does not change a phase characteristic of the vehicle horizontal acceleration after the adjustment. When a vehicle vertical location as the vertical deviation quantity is calculated by a second order integration of a vehicle vertical acceleration, the gain and the cutoff frequency of the Bessel filter are adjusted in response to the vehicle running speed. The waveform distortion is prevented from being generated since the Bessel filer does not change a phase characteristic of the vehicle vertical acceleration after the adjustment. The versine waveforms having various chord lengths can be output in real time. COPYRIGHT: (C)2010,JPO&INPIT

Proceedings ArticleDOI
01 Dec 2009
TL;DR: A 40mW 0.059mm2 analog video pre-processing is presented and an AGC with two gain characteristics are implemented which achieves 51dB SNDR for a 60MHz input and a filter corner frequency of 78MHz.
Abstract: A 40mW 0.059mm2 analog video pre-processing is presented. Pseudo differential inputs and an AGC with two gain characteristics are implemented. These gain characteristics are realized by simply adding one resistor to the existing topology. Two single ended low noise input buffers are used in unity gain configuration to operate the AGC. The ADC is driven by a binary weighted 4th order Bessel filter which is optimized for power and area. It is fabricated in a 90nm 1.2V CMOS process and achieves 51dB SNDR for a 60MHz input and a filter corner frequency of 78MHz.

Proceedings ArticleDOI
15 Mar 2009
TL;DR: A method is presented for generating a maximally-flat chirp signal whose effective duration is controllable by a single parameter and is demonstrated by their application to the spectral analysis of audio systems including multimedia sound cards and a cassette tape recorder.
Abstract: A method is presented for generating a maximally-flat chirp signal whose effective duration is controllable by a single parameter. A sequence of discrete sample values is calculated, each of which is equal to the nth-order Bessel function at a fixed argument. The effective duration of this sequence is approximately twice the value of the argument. Standard analog-to-digital conversion methods can be used to produce a time-varying analog signal for system test and evaluation. The utility of these signals is demonstrated by their application to the spectral analysis of audio systems including multimedia sound cards and a cassette tape recorder.