Serial fiber over WIFI howe?


I want to send serial data from fiber optic over WIFI with
ZNET2.5 Xbee,s.
I wil cut the fiber, connect to a adapter with optical send diode or lazer and transmit with Xbee and read with Xbee and proces data with ? and put on fiber again. Just transparant operation one way.
Of course we must know the bit rate etc, But I can,t find lazer diode, chips to proces the data etc. Wil UART do the job? I have experience with wifi with Xbee
Who has a clou?