Dear Kinzah
First of all be clear about FSO channel and Optical-Wireless Terrestrial channel as both are different.You are advised to study literature over it.Secondly, the simulation setup you pasted over MS Word file is that FSO channel.In one of the eye diagram your BER is maximum while in other its 0.Both the cases are far away from real simulations. You are again advised to simulate smaller and simpler FSO system e.g like OOK transmission over FSO channel of some hunderds of meter like and then go for complex ones
hope this will work