Added presentation; DE-QPSK; CD with FFT; split-step Fourier

[4yp.git] / CDCompensation.m

diff --git a/CDCompensation.m b/CDCompensation.m
index 0fec7c8..1f3cc2c 100644 (file)
--- a/CDCompensation.m
+++ b/CDCompensation.m
@@ -1,4 +1,4 @@
-function yCDComp = CDCompensation(y, D, lambda, z, Tsamp)
+function [yCDComp, kstart] = CDCompensation(y, D, lambda, z, Tsamp)
   %% Chromatic dispersion compensation.
   %% Params:
   %%  - y: received waveform with CD
@@ -18,6 +18,7 @@ function yCDComp = CDCompensation(y, D, lambda, z, Tsamp)
   %% Implementing Eq. (9) in [1].
   N = 2 * floor(abs(D) * lambda^2 * z / (2 * c * Tsamp^2)) + 1;
   k = -floor(N / 2) : floor(N / 2);
+  kstart = -floor(N/2);
 
   % h: FIR filter
   h = sqrt(j * c * Tsamp^2 / (D * lambda^2 * z)) * ...