Novel 2-D Wavelength Hopping/Time Spreading OCDM System using Heterodyne Detection Receiver and PPM Signaling

We propose and theoretically analyze the performance of two-dimensional wavelength hopping/time spreading optical code division multiplexing (2-D WH/TS OCDM) systems using heterodyne detection receiver and pulse-position modulation (PPM) signaling The analysis is carried out taking into account various kinds of noise and interference, including multiple access interference (MAI), optical beating interference (OBI), crosstalk and receiver´s noise. We compare the performance of the proposed system with the one using OOK signaling. Numerical results show the improvement in both number of users and optical power gain. In particular, when the PPM signaling with M = 4 is used, we can achieve a more than 6 times increase in the number of users and an optical power gain of 15 dB in comparison with the conventional system.