thank you Dhananjay. actually i am weighing up the option of upgrading my 12 license to 13. but i am not sure what is the advantage of OFDM in 13. can you advice me on that matter.
also the attenuation value is not what i am gonna use in my project. my real project would be convert rain rate to attenuation using Matlab then use the attenuation to run simulation. the FSO component block in Optisystem is rather too simple as we can only manipulate the attenuation in fact there are too many aspect that can affect the propagation. i think Optiwave should consider this in future upgrade.