Showing papers on "Bessel filter published in 2013"
TL;DR: This study investigated the effect of various standard filters on the morphology and measurement of extracellular gastric slow waves.
Abstract: Background Extracellular recordings are used to define gastric slow wave propagation. Signal filtering is a key step in the analysis and interpretation of extracellular slow wave data; however, there is controversy and uncertainty regarding the appropriate filtering settings. This study investigated the effect of various standard filters on the morphology and measurement of extracellular gastric slow waves.
Methods Experimental extracellular gastric slow waves were recorded from the serosal surface of the stomach from pigs and humans. Four digital filters: finite impulse response filter (0.05–1 Hz); Savitzky-Golay filter (0–1.98 Hz); Bessel filter (2–100 Hz); and Butterworth filter (5–100 Hz); were applied on extracellular gastric slow wave signals to compare the changes temporally (morphology of the signal) and spectrally (signals in the frequency domain).
Key Results The extracellular slow wave activity is represented in the frequency domain by a dominant frequency and its associated harmonics in diminishing power. Optimal filters apply cutoff frequencies consistent with the dominant slow wave frequency (3–5 cpm) and main harmonics (up to ∼2 Hz). Applying filters with cutoff frequencies above or below the dominant and harmonic frequencies was found to distort or eliminate slow wave signal content.
Conclusions & Inferences Investigators must be cognizant of these optimal filtering practices when detecting, analyzing, and interpreting extracellular slow wave recordings. The use of frequency domain analysis is important for identifying the dominant and harmonics of the signal of interest. Capturing the dominant frequency and major harmonics of slow wave is crucial for accurate representation of slow wave activity in the time domain. Standardized filter settings should be determined.
64 citations
TL;DR: The modified Bessel collocation method is presented to obtain the approximate solutions of the linear Lane-Emden differential equations using the improvement of the Bessel polynomial solutions with the aid of the residual error function.
41 citations
TL;DR: The main object of as mentioned in this paper is to give sufficient conditions for certain families of integral operators which are defined by means of the normalized form of the generalized Bessel functions to be convex of given order in the open unit disk.
Abstract: The main object of this paper is to give sufficient conditions for certain families of integral operators which are defined by means of the normalized form of the generalized Bessel functions to be convex of given order in the open unit disk. In particular cases, we find the corresponding simple conditions for integral operators involving the Bessel function, the modified Bessel function and the spherical Bessel function.
32 citations
TL;DR: A revitalization effort towards exploiting multilevel polybinary signals for spectral efficient data links by proper coding to avoid error propagation and degeneracy of the bit error rate performance is presented.
Abstract: This paper presents a revitalization effort towards exploiting multilevel polybinary signals for spectral efficient data links. Specifically, we present five level polybinary signaling for 10 Gbps signals. By proper coding to avoid error propagation and degeneracy of the bit error rate performance, a 10Gbps polybinary signal is successfully generated employing a 1.8 GHz Bessel filter with an electrical spectral efficiency of 5.5 bit/s/Hz. The experimental results show bit error rate performances below FEC level for transmission in singlemode and dispersion shifted fibers up to 20 km length.
28 citations
TL;DR: The integrals are transformed into the problems involving the complex exponential functions, which can be efficiently computed by using the complex integration method, and the entirely different asymptotic expansions from the references are obtained.
25 citations
TL;DR: In this paper, the authors studied the application of the fractional Hankel transformation (FrHT) in solving generalized n th order linear nonhomogeneous ordinary differential equations and the continuous fractional Bessel wavelet transformation.
Abstract: The main objective of this paper is to study the fractional Hankel transformation and the continuous fractional Bessel wavelet transformation and some of their basic properties. Applications of the fractional Hankel transformation (FrHT) in solving generalized n th order linear nonhomogeneous ordinary differential equations are given. The continuous fractional Bessel wavelet transformation, its inversion formula and Parseval’s relation for the continuous fractional Bessel wavelet transformation are also studied. MSC:46F12, 26A33.
17 citations
TL;DR: In this article, a pyramidal scheme using the interlacing property of the cross-product of Bessel functions is proposed to find the roots of the zeroth order using an auxiliary function that exhibits the same roots as the original cross-products.
Abstract: This paper describes an algorithm to calculate a large number of roots of the cross-product of Bessel functions and of their first derivatives. The algorithm initially finds the roots of the zeroth order using an auxiliary function that exhibits the same roots as the original cross-products but with better behavior for numerical root search with the Newton–Raphson algorithm. In order to find the roots for higher orders, the algorithm follows a pyramidal scheme using the interlacing property of the cross-product of Bessel functions. The algorithm shows globally convergent behavior for a large range of values of the argument and of the order of the Bessel functions. The roots can be computed to any precision, limited only by the computer implementation, and the convergence is attained in six iterations per root in average, showing a much better performance than previous works for the calculation of these roots.
12 citations
TL;DR: Using a generalized translation operator, this article obtained an analog of Theorem 5.2 in Younis (1986) for the Bessel transform for functions satisfying the -Bessel Lipschitz condition in.
Abstract: Using a generalized translation operator, we obtain an analog of Theorem 5.2 in Younis (1986) for the Bessel transform for functions satisfying the -Bessel Lipschitz condition in .
11 citations
TL;DR: This article shows that this can be accomplished through phase-only shaping of the wavefront in the far field where the beam has an annular ring structure with a Gaussian cross section and optimized the axial intensity with a Gerchberg-Saxton algorithm.
Abstract: Gaussian-apodized Bessel beams can be used to create a Bessel-like axial line focus at a distance from the focusing lens. For many applications it is desirable to create an axial intensity profile that is uniform along the Bessel zone. In this article, we show that this can be accomplished through phase-only shaping of the wavefront in the far field where the beam has an annular ring structure with a Gaussian cross section. We use a one-dimensional transform to map the radial input field to the axial Bessel field and then optimized the axial intensity with a Gerchberg-Saxton algorithm. By separating out the quadratic portion of the shaping phase the algorithm converges more rapidly.
11 citations
TL;DR: The proposed approach for the detection of the VOT using the Bessel expansion is shown to perform better than the conventional Fourier representation and the proposed GCI detection method is compared against some of the existing methods for various noise environments and signal-to-noise ratios.
Abstract: In this paper, we propose an approach for the analysis and detection of acoustic events in speech signals using the Bessel series expansion. The acoustic events analyzed are the voice onset time (VOT) and the glottal closure instants (GCIs). The hypothesis is that the Bessel functions with their damped sinusoid-like basis functions are better suited for representing the speech signals than the sinusoidal basis functions used in the conventional Fourier representation. The speech signal is band-pass filtered by choosing the appropriate range of Bessel coefficients to obtain a narrow-band signal, which is decomposed further into amplitude modulated (AM) and frequency modulated (FM) components. The discrete energy separation algorithm (DESA) is used to compute the amplitude envelope (AE) of the narrow-band AM-FM signal. Events such as the consonant and vowel beginnings in an unvoiced stop consonant vowel (SCV) and the GCIs are derived by processing the AE of the signal. The proposed approach for the detection of the VOT using the Bessel expansion is shown to perform better than the conventional Fourier representation. The performance of the proposed GCI detection method using the Bessel series expansion is compared against some of the existing methods for various noise environments and signal-to-noise ratios.
9 citations
23 May 2013
TL;DR: The main aim of this article is to establish summation formulae in form of sampling expansion series for Bessel functions Yv, Iv; and Kv, and obtain sharp truncation error upper bounds occurring in the Y-Bessel sampling series approximation.
Abstract: The main aim of this article is to establish summation formulae in form of sampling expansion series for Bessel functions Yv, Iv; and Kv, and obtain sharp truncation error upper bounds occurring in the Y-Bessel sampling series approximation. The principal derivation tools are the famous sampling theorem by Kramer and various properties of Bessel and modified Bessel functions which lead to the so-called Bessel sampling when the sampling nodes of the initial signal function coincide with a set of zeros of different cylinder functions.
12 Dec 2013
TL;DR: A novel circuit architecture for implementing the Bessel low-pass filter with an ultra-low corner frequency and negligible interferences from the ground is presented, based on the transconductance-capacitor (Gm-C) architecture.
Abstract: Active filters with a very low corner frequency (of only a few hertz or below) are usually demanded at the frontend circuitry of biomedical instruments. This paper presents a novel circuit architecture for implementing the Bessel low-pass filter with an ultra-low corner frequency and negligible interferences from the ground. Basing on the transconductance-capacitor (Gm-C) architecture, the proposed filter incorporates a differential amplifier into the negative feedback loop to scale down the corner frequency, as well as to eliminate noise coupling from the ground. To demonstrate the design concept, a second-order Bessel filter is fabricated with the 0.35μm CMOS technology. With a corner frequency of around 1Hz, the filter consumes only 1.2μW and a chip area of 0.089mm2. Moreover, the 60-Hz interference from the ground is proved to be attenuated by more than 36dB.
TL;DR: In this article, a Green's function based solver for the modified Bessel equation has been developed with the primary motivation of solving the Poisson and biharmonic equations in cylindrical geometries.
Abstract: A Green’s function based solver for the modified Bessel equation has been developed with the primary motivation of solving the Poisson and biharmonic equations in cylindrical geometries. The method is implemented using a Discrete Hankel Transform and a Green’s function based on the modified Bessel functions of the first and second kind. The computation of these Bessel functions has been implemented to avoid scaling problems due to their exponential and singular behaviour, allowing the method to be used for large order problems, as would arise in solving the Poisson equation with a dense azimuthal grid. The method has been tested on monotonically decaying and oscillatory inputs, checking for errors due to interpolation and/or aliasing. The error has been found to reach machine precision and to have computational time linearly proportional to the number of nodes.
TL;DR: In this article, a beam forming approach capable of synthesizing versatile, pre-specified beam shapes using concentric excitations satisfying multiple weighted sinc or Bessel function distribution is proposed.
Abstract: In this paper, we propose a beam forming approach capable of synthesizing versatile, pre-specified beam shapes using concentric excitations satisfying multiple weighted sinc or Bessel function distribution. We show by both theoretical calculation and full wave simulation that by tuning different weights of a sinc or Bessel function distribution, not only radiation beams with pencil, flat-topped and bimodal shapes can be synthesized, but also the beam-width and the side lobe level can be independently adjusted. An example is provided to demonstrate how an isoflux beam aiming at a better coverage of the earth surface is synthesized, and how an optimized continuous distribution is properly discretized for a physical realization of a satellite aperture array antenna. The approach proposed in this paper can be applied to a wide range of applications that require performance optimization of concentric ring array antennas.
TL;DR: The pole extraction and regularization of singular Hankel series is performed, for integer Gaussian power-law densities as well as for the special case of Kummer averages and the singular @e residuals are used to derive combinatorial identities for the rational Hankel coefficients, which serve as consistency checks in precision calculations of the integrals.
01 Jan 2013
TL;DR: In this paper, a generalization of Theorem 2.2 in (3) for the Bessel transform for functions satisfying the ( ;; )-Bessel Lipschitz condition in the space L 2; (R + ).
Abstract: Using a Bessel translation operator, we obtain a generalization of Theorem 2.2 in (3) for the Bessel transform for functions satisfying the ( ;; )- Bessel Lipschitz condition in the space L2; (R + ).
Book•
12 Mar 2013TL;DR: In this article, the effect of pulse shaping QPSK on bandwidth efficiency over a non-linear channel was investigated using software simulations and the hardware implementation, and a significant improvement in the bandwidth utilization for the filtered data compared to unfiltered data through the nonlinear channel is shown in the results.
Abstract: This research investigates the effect of pulse shaping QPSK on bandwidth efficiency over a non-linear channel. This investigation will include software simulations and the hardware implementation. Three kinds of filters: the 5th order Butterworth filter, the 3rd order Bessel filter and the Square Root Raised Cosine filter with a roll off factor (alpha) of 0.25,0.5 and 1, have been investigated as pulse shaping filters. Two different high power amplifiers, one a Traveling Wave Tube Amplifier (TWTA) and the other a Solid State Power Amplifier (SSPA) have been investigated in the hardware implementation. A significant improvement in the bandwidth utilization (rho) for the filtered data compared to unfiltered data through the non-linear channel is shown in the results. This method promises strong performance gains in a bandlimited channel when compared to unfiltered systems. This work was conducted at NMSU in the Center for Space Telemetering, and Telecommunications Systems in the Klipsch School of Electrical and Computer Engineering Department and is supported by a grant from the National Aeronautics and Space Administration (NASA) NAG5-1491.
TL;DR: In this paper, a peak current control with extended-state tracking compensator is introduced to deal with the stability of hybrid energy storage system (HESS) application. But the gains of the control algorithm are selected based on pole locations formulated from the Bessel filter.
Abstract: Because variations of ultra-capacitor voltage and battery voltage generate subharmonic and chaotic behaviors in hybrid energy storage system (HESS) application when a DC-DC converter is under the peak current control, a novel digital control strategy, i.e., peak current control with extended-state tracking compensator, is introduced to deal with the stability. The gains of the control algorithm are selected based on pole locations formulated from the Bessel filter. The simulation results validate that under the peak current control strategy with compensator, the DC-DC converter does not have the subharmonic and chaotic behaviors. The response time under the peak current control with compensator is the same as that under the peak current control. The ripple voltage and ripple current of battery are less. The tracking error of inductor current tends to zero.
Proceedings Article•
01 Sep 2013TL;DR: A novel discrete-time FIR fractional delay special filter is investigated, a Nyquist filter which has the ability to compensate for subsample transmission delay involved, for example, in multipath propagation channel.
Abstract: In the paper a novel discrete-time FIR fractional delay special filter is investigated. This is a Nyquist filter which, besides the traditional its attribute (intersymbol interference (ISI) free property), has the ability to compensate for subsample transmission delay involved, for example, in multipath propagation channel. The performance of the filter is analysed and illustrated.
TL;DR: In this article, the step response is good and fast, and no excess, while the feedback gain is obtained according to the analysis of Bessel filter, and the design of state feedback is proved fast and no overshoot.
Abstract: The feedback gain is gotten according to the analysis of Bessel filter .The step response is good and fast, and no excess. Appling to the design of state feedback, it is proved fast and no overshoot. It is a good correct method.
11 Apr 2013
TL;DR: This paper presents the design of the three-way crossover network by using Bernstein polynomial which has the best characteristics with more advantages and is converted into the digital filter by using the bilinear transformation.
Abstract: This paper presents the design of the three-way crossover network by using Bernstein polynomial. The Bernstein polynomial is applied to the Bernstein filter which has the best characteristics with more advantages. For example, it has a maximally flat magnitude, a linear-phase and a maximally flat delay with parameters of n , K ande . For this reason, the three-way crossover network is designed by Bernstein filter. Moreover, the analog filter is converted into the digital filter by using the bilinear transformation. Both analog filter and digital filter have better performance for designing the three-way crossover network. In addition, the experimental results at the real time of the three-way crossover network can realize via FiO Board and RapidSTM32.