Fig. 1. 10 Gb/s 2D FSO-CDMA wiretap channel.

Fig. 2. Optical encoder and decoder based on WSS and ODLs.

Fig. 3. Received signal waveforms: (a) middle turbulence and (b) weak turbulence.

Fig. 4. Eye diagrams of middle turbulence: (a) diversity and (b) no diversity.

Fig. 5. BERs in weak and middle turbulence conditions.

Fig. 6. Eve’s eye diagrams with an extract ratio of 1%: (a) encoded and (b) uncoded.

Fig. 7. Eve’s BER with an extract ratio of 1%.