Impact of Atmospheric Turbulence on the Performance of 2-D WH/TS OCDMA with APD-based Receiver

The performance of two-dimensional wavelength-hopping/time-spreading optical code division multiple access (2-D WH/TS OCDMA) system is investigated analytically in the presence of atmospheric turbulence and adverse atmospheric conditions. The analysis is carried out over free space optic (FSO) channel with different system parameters operating at a wavelength of 1550 nm. The gamma-gamma model is studied for the analysis of strong atmospheric turbulence. Avalanche photodiode (APD) is employed for functioning the optoelectronic conversion. The 2-D prime code is used as user code address. The bit error rate (BER) performance is demonstrated in terms of proposed system parameters. It is observed that the BER is immensely subjected to strong atmospheric turbulence. It can be found that the system performance is poor to sustain an increased number of simultaneous users over a strong atmospheric channel.