init

FOTF Toolbox/ousta_fod.m

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+function G=ousta_fod(gam,N,wb,wh)
+% ousta_fod - design of an Oustaloup filter
+%
+%    G=ousta_fod(r,N,wb,wh)
+%
+%   r - the fractional order
+%   wb, wh, N - the interested frequency interval (wb,wh) and the order
+%   G - the designed Oustaloup filter, as a TF object
+   
+% Copyright (c) Dingyu Xue, Northeastern University, China
+% Last modified 28 March, 2017 
+% Last modified 18 May, 2022 
+   arguments
+      gam(1,1) double, N(1,1){mustBePositiveInteger}=9
+      wb(1,1) double=1e-4; wh(1,1){mustBeGreaterThan(wh,wb)}=1e4;
+   end
+   if round(gam)==gam, G=tf('s')^gam;
+   else
+      k=1:N; wu=sqrt(wh/wb);
+      wkp=wb*wu.^((2*k-1-gam)/N); wk=wu^(2*gam/N)*wkp;
+      G=zpk(-wkp,-wk,wh^gam);
+end, end