Performance bounds for Turbo-coded SC-PSK/FSO communications over strong turbulence channels

This paper comprehensively investigates the performance of the Turbo-coded free-space optical (FSO) system using subcarrier phase shift keying (SC-PSK) signaling. We obtain theoretical bounds for the system's bit-error rate (BER) and channel capacity over the gamma-gamma strong turbulence channels in both uncoded and Turbo-coded cases. We quantitatively show that the BER and channel capacity are considerably affected by the strong turbulence. In Turbo-coded systems, a coding gain of about 4 dB and 5% channel capacity increase can be achieved in the strong turbulence regime.