OTFS_modulation.m

%
% Copyright (c) 2018, Raviteja Patchava, Yi Hong, and Emanuele Viterbo, Monash University
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%    - Latest version of this code may be downloaded from: https://ecse.monash.edu/staff/eviterbo/
%    - Freely distributed for educational and research purposes
%%
function s = OTFS_modulation(M,N,x) % x in MxN
%% OTFS Modulation: 1. ISFFT, 2. Heisenberg transform
X = fft(ifft(x.').')/sqrt(M/N); %%%ISFFT
s = ifft(X)*sqrt(M); % Heisenberg transform
% s = s(:);
end