X-Git-Url: https://adrianiainlam.tk/git/?a=blobdiff_plain;f=CD_AWGN.m;h=241d22a66839a16e93452f377593fd4aeedeaca7;hb=934d76babd9beed87a3ef60a075b556a63899fed;hp=4db7aad3c0dffa66d2a0c434aac9e988963a9bee;hpb=f9a73e9e2254af8edeb8a34185e98cd8c809ac0e;p=4yp.git

diff --git a/CD_AWGN.m b/CD_AWGN.m
index 4db7aad..241d22a 100644
--- a/CD_AWGN.m
+++ b/CD_AWGN.m
@@ -1,18 +1,18 @@
-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;
@@ -36,26 +36,30 @@ x = txFilter(modData, rolloff, span, sps);
 %% 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;