function res = kaiserBessel(m,alpha,a,r) %------------------------------------------------------------------------ % res = kaiserBessel(m,alpha,a,r) % % Calculates the Kaiser windowing function % % a: length of the sequence. % m: order. % alpha: determines shape of window. % r: input values for which to compute window value. % res: the window values. %------------------------------------------------------------------------ %------------------------------------------------------------------------ % This file is part of the ASTRA Toolbox % % Copyright: 2010-2018, imec Vision Lab, University of Antwerp % 2014-2018, CWI, Amsterdam % License: Open Source under GPLv3 % Contact: astra@astra-toolbox.com % Website: http://www.astra-toolbox.com/ %------------------------------------------------------------------------ sq = sqrt(1 - (r./a).^2); res1 = 1 ./ besseli(m, alpha); res2 = sq .^ m; res3 = besseli(m, alpha .* sq); res = res1 .* res2 .* res3;