Performance evaluation of underwater wireless optical CDMA system for different water types

In this paper, an analytical approach is presented to investigate the bit error rate (BER) performance of underwater wireless optical code division multiple access system for different water types. Optical orthogonal codes (OOC) are used as the user-specific address sequence to encode and decode the user's data. LED with an operating wavelength of 532 nm is used as the optical source, and silicon avalanche photodiode is used as the optical detector. The system BER performance is analyzed on account of transmission distance, transmitted power, number of simultaneous users, and other system parameters where different water types (i.e., pure sea water, clear ocean water, and coastal ocean water) are considered as the communication channel qualities. It is found that the BER performance of this system significantly depends on the water types. However, the best overall system performance is achieved in pure sea water where clear ocean water provided better results than coastal ocean water.