--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/m-toolbox/classes/@specwin/kaiser_w3db.m	Wed Nov 23 19:22:13 2011 +0100
@@ -0,0 +1,26 @@
+function w3db = kaiser_w3db(alpha)
+
+% KAISER_W3DB returns the 3dB bandwidth in bins of a kaiser window with
+% parameter alpha.
+% 
+% Taken from C code of Gerhard Heinzel:
+% 
+%    Compute the 3dB bandwidth (W3db) [bins]
+%    of Kaiser windows from the parameter alpha.
+%    Best-fit polynomial was obtained from 180 data 
+%    points between alpha=1 and alpha=9.95.
+%    Maximum error is 0.006 bins.
+% 
+% M Hewitson 19-05-07
+% 
+% $Id: kaiser_w3db.m,v 1.2 2011/04/08 08:56:35 hewitson Exp $
+% 
+
+a0   = 0.757185;
+a1   = 0.377847;
+a2   = -0.0238342;
+a3   = 0.00086012;
+x    = alpha;
+w3db = (((((a3 * x) + a2) * x) + a1) * x + a0);
+
+% END