Journal of Theoretical and Applied Information Technology
In the past two decades, wireless communications has attracted vast popularity in which Radio Frequency (RF) and Optical Wireless (OW) have been applied for transferring data. OW has the potential to be an alternative to RF and fiber optic communication systems. WDM technique can be easily integrated with outdoor OWC systems and it can significantly increase the bitrate in OWC systems. This paper describes reviews of the current state of the art WDM-based OWC systems. Then, challenges of WDM-based OWC are clustered.