close all;
N=10000;
data=(round(rand(1,N)));
N_dane=2000;
bitrate=250;
UF=N_dane/bitrate;
% tu se odkomentuj cos co ci trzeba (bi = manchester)
% nrz=upsample(data,UF);
% nrz=conv(nrz,ones(1,UF));
%
% rz=upsample(data,UF);
% rz=conv(rz,ones(1,UF/2));

bi=upsample(data-0.5, UF);
bi=conv(bi, [ones(1,UF/2)  -ones(1,UF/2)]);

s=1;
ami=zeros(1,N);

for n=1:N
    if(data(n)==1)
        s=s*(-1);
        ami(n)=s;
    elseif(data(n)==0)
        ami(n)=0;
    end
end

ami=upsample(ami,UF);
ami=conv(ami,ones(1,UF));

%s=ami;
s=bi-0.5;
%s=rz-0.25;
figure
plot(s(1:200))

figure
per=periodogram(s,hamming(length(s)));
plot(per)
title('periodogram');

figure
WIN=200;
%pwelch - estymator welcha(sygna l, okno,ilosc probek overalp, wymiar fft)
pw=pwelch(s,hann(WIN), 0, WIN);
plot(pw)
title('Bartletta');

figure
WIN=200;
%pwelch - estymator welcha(sygna l, okno,ilosc probek overalp, wymiar fft)
pw=pwelch(s,hann(WIN),UF/2, WIN);
plot(pw)
title('Welcha');