-numSymbs = 5e5;
+numSymbs = 2^16;
M = 4;
Rsym = 2.5e10; % symbol rate (sym/sec)
rolloff = 0.25;
span = 6; % filter span
-sps = 2; % samples per symbol
+sps = 8; % samples per symbol
fs = Rsym * sps; % sampling freq (Hz)
Tsamp = 1 / fs;
t = (0 : 1 / fs : numSymbs / Rsym + (1.5 * span * sps - 1) / fs).';
-EbN0_db = 0:0.2:14;
+EbN0_db = 0:0.5:14;
EbN0 = 10 .^ (EbN0_db ./ 10);
Es = 1;
%% Simulate chromatic dispersion
D = 17; % ps / (nm km)
lambda = 1550; % nm
-z = 60;%000; % km
+z = 3000; % km
-usingFFT = 1
-xCD = chromaticDispersion_FFT(x, D, lambda, z, Tsamp);
-%%xCD = normalizeEnergy(xCD, numSymbs, 1);
-%%xCD = x;
+
+[xCD, xCDkstart] = chromaticDispersion(x, D, lambda, z, Tsamp);
+
+TsampOrig = Tsamp;
for i = 1:plotlen
+ sps = 8;
+
snr = EbN0_db(i) + 10 * log10(log2(M)) - 10 * log10(sps);
- noiseEnergy = 10 ^ (-snr / 10);
y = awgn(xCD, snr, 'measured');
- %%y = xCD;
r = rxFilter(y, rolloff, span, sps);
- rCDComp = CDCompensation(r, D, lambda, z, Tsamp);
+
+ sps = 2;
+ Tsamp = TsampOrig * 4;
+
+ [rCDComp, CDCompkstart] = CDCompensation(r, D, lambda, z, Tsamp);
rCDComp = normalizeEnergy(rCDComp, numSymbs*sps, 1);
- rSampled = rCDComp(sps*span/2+1:sps:(numSymbs+span/2)*sps);
- rNoCompSampled = r(sps*span/2+1:sps:(numSymbs+span/2)*sps);
+ rSampled = rCDComp(2:2:end);
+ rNoCompSampled = r(2:2:end);
%% rotate rNoCompSampled to match original data
theta = angle(-sum(rNoCompSampled .^ M)) / M;