i2r.m

blind 多径信道中盲信道均衡的恒模算法

function y=i2r(x)
% y = i2r(x)
%    Takes a frequency signal and prepares it for IFFT
%    (IFFT of original signal would be imaginary.  "Doubling"
%    of signal provides symmetry to make IFFT output real.)
%
%    This version taken from FRODO/MERRY files on 05/20/2002
%    Written by Rick Martin, last updated on 05/20/2002
%    Cornell University Blind Equalization Research Group
%
%     Copyright 2002 Cornell University, All Rights Reserved
%
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%     ("CRF") Docket D-3006.  SOFTWARE is made available to allow
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%     the use or results of SOFTWARE with respect to its
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y = [sqrt(2)*real(x(1)) x(2:length(x)) ...
     sqrt(2)*imag(x(1)) conj(fliplr(x(2:length(x))))];

% The factors of sqrt(2) make E[y y^h] = constant * eye(N)