Enhancement of free space optical communication system modulation using DDM technique

Many FSO communication systems are using a conventional technique that is OOK technique in the system. Some enhancement of technique is explained in this paper to decrease the error rate that occurs in the system. The comparison between OOK technique and DDM technique is investigated in order to compare the error rate and power received. The result shows that the performance of DDM technique generates improvement as much as 21% magnitude of BER in the system.