Showing papers on "Bessel filter published in 1987"
38 citations
TL;DR: In this paper, a method for generating Bessel functions J n (z)Y n(z) and their derivatives, where z is complex and n an integer, is presented.
Abstract: Algorithms have been presented for generating the Bessel functions J n (z)Y n (z) and their derivatives, where z is complex and n an integer. The values of the functions generated by the proposed method are accurate to almost as many significant places as are available on the computer. Also, the ranges of n and z for which the functions can be generated to this accuracy are limited only by the overflow and underflow limits of the machine. The methods and the numerical aspects of the problem have been discussed in detail. The computed results of the functions for real and complex arguments have been checked against standard tables wherever possible. Some sample tables for specific values of n and z have also been presented.
2 citations
Patent•
24 Aug 1987
TL;DR: In this article, a subtraction circuit was proposed to cancel noise generated in a low frequency area by previously reducing the noise generated by the pre-stage of a limiter and canceling the noises generated in the limiter.
Abstract: PURPOSE:To cancel noise generated in a low frequency area by previously reducing the noise generated in the second signal band by the prestage of a limiter and canceling the noise generated in the limiter. CONSTITUTION:A subtraction circuit 8 subtracts the output of the second Bessel filter from the output of the first Bessel filter to separate only the noise component of the second signal band. The noise component is adjusted in its level in the second gain control circuit 9 and conducted out, while a delay circuit 10 delays an addition output by a prescribed time in order to set the addition output to the quantity of the delay of such a noise component. Accordingly, the second subtraction circuit 11 subtracts the noise component to be generated in a succeeding time from the addition output. The negative noise component in the second subtraction output cancels the noise component generated by the second limiter 12. The second slice level adjusting circuit 13 adjusts the slice level similarly to the first lice level adjusting circuit 13 so as to induce no asymmetrical noise from the second limiter 12.