Performance analysis of Spectral Amplitude Coding-Optical Code Division Multiple Access (SAC-OCDMA) in free space optical networks with a multi-wavelength laser source

We present spectral amplitude coding, optical code division multiple access technique in free space optical network utilizing multi-wavelength laser source. Using the simulation software, the system performance is analysed while the impact of the turbulence is also considered. The simulation is implemented using modified double weight (MDW) code and for three users. The results show that using receiver aperture diameter, D, of 4 cm and beam divergence, θ, of 1 mrad, transmission distance 2.8, 2.45 and 2.25 km is achievable for weak, moderate and strong turbulence, respectively. This distance can be improved if bigger D or smaller θ were utilized; moreover, it is shown that the increment of turbulence increases jitter, which downgrades system performance.