Showing papers on "Bessel filter published in 1990"
01 May 1990
TL;DR: The transconductance-C filter is unique in its dual emphasis on magnitude and constant group delay characteristics and shows great promise for other future applications, potentially up to 100 MHz.
Abstract: Design and experimental verification of a fully differential monolithic bipolar seventh-order Bessel lowpass filter are presented. The transconductance-C filter is unique in its dual emphasis on magnitude and constant group delay characteristics. Its pole frequency f/sub c/ is current tunable between 5 and 15 MHz. The circuit also incorporates user programmable equalization. Measured group delay variation with and without equalization is less than 1 ns between DC and 1.5 f/sub c/. With 5-V operation and 2-V/sub pp/ input signal, the total harmonic distortion is less than 1%. The filter is primarily targeted at high-performance disk drives and constant density recording applications. Its design generality and excellent high-frequency performance show great promise for other future applications, potentially up to 100 MHz. >
33 citations
01 Feb 1990
TL;DR: In this paper, an elementary Sturm technique is used to provide an alternative and simpler proof of the result that the known monotonicity of the zeros of fixed rank of the Bessel function of the first kind implies monotoneness for the zero of its derivative for orders between -1 and 0.
Abstract: An elementary Sturm technique is shown to provide an alternative and simpler proof of the result that the known monotonicity of the zeros of fixed rank of the Bessel function of the first kind implies monotonicity for the zeros of its derivative for orders between -1 and 0. The reasoning applies to other Bessel functions.
5 citations
3 citations
01 Jan 1990
TL;DR: In this article, Laforgia and Muldoon studied monotonicity of aafc and (a + 2) aak in the generalized Airy equation and showed that the monotoneness of the Bessel function is monotonically characterized by the fc-th positive zero of a solution of the generalized airy equation.
Abstract: TJie &-th positive zero of a solution of the generalized Airy equation y" + x?t = 0, <*ak = [cykl(2v)], where cVk is the fc-th positive zero of the Bessel function Cv(x) and v = l/(a 42)» Laforgia and Muldoon [ZAMP, 39, 1988, 267-271] have studied monotonicity in « of aafc and (a + 2) aak. Additional such properties are presented here.
1 citations
TL;DR: In this paper, a gaussian quadrature method is used to obtain precise values of important Bessel function integrals, where the function is characterized in terms of the number of quadratures points that are required to obtain a specified precision.
22 Jan 1990
TL;DR: In this paper, a linear time invariant filter was designed to generate a prescribed delay using minimum mean square error criteria. But the performance of the filter was evaluated by comparing the correlation of the signal with the doppler shifted signal.
Abstract: Time companding of broad band signals or doppler shifts of sinusoidal signals can be interpreted as linearly time varying delay. For any stationary signal, a linear time invariant filter can always be designed to generate a prescribed delay using minimum mean square error criteria . A FIR filter of order 2m is sufficient to generate any delay with zero mean square error for signal consisting of m sinusoidals. The coefficients of such a filter are derived by solving normal equations. By using time varying delay parameter for estimation the solution of normal equation generates time varying filter coefficients. This fiIter produces appropriate doppler shifts. Here an expression is derived for the filter coefficients. The performance of the filter is evaluated by comparing the correlation of the signal with the doppler shifted signal.