function y=anastep(N,ti);%ANASTEP Analytic projection of unit step signal.%	Y=ANASTEP(N,TI) generates the analytic projection of a%	unit step signal.%	%	N  : number of points.%	TI : starting position of the unit step.%	%	Examples :%	 signal=anastep(256,128);plot(real(signal));%	 signal=-2.5*anastep(512,301);plot(real(signal));%%	See also ANASING, ANAFSK, ANABPSK, ANAQPSK, ANAASK.%	O. Lemoine - June 1995, F. Auger, August 1995.%	Copyright (c) 1996 by CNRS (France).%%	------------------- CONFIDENTIAL PROGRAM -------------------- %	This program can not be used without the authorization of its%	author(s). For any comment or bug report, please send e-mail to %			    lemoine@alto.unice.fr if (nargin==0), error('at least one parameter required');elseif (nargin==1), ti=round(N/2);end;if (N<=0), error('N must be greater than zero');else t=(1:N)'; y=hilbert(t>=ti);end;