What is Free Space Optics (FSO)?

Free space optics (FSO) is a line-of-site technology that uses lasers to provide optical bandwidth connections and is capable of 2.5 Gbps of data, voice and video communications. The use of lasers is a simple concept similar to optical transmissions using fiber-optic cables;the only difference is the medium.

FSO Technology

FSO technology is based on connectitvity between FSO units, each consisting of an optical transceiver with a laser transmitter and a receiver to provide full duplex(bi-directional) capability. It requires no spectrum licensing and it is easily upgradeable, which helps service providers protect their investment in embedded telecommunications infrastructures.

How it works

FSO involves the optical transmission of voice, video, and data using air as the medium of transmission as opposed to fiber optic cable. It involves two systems each consisting of an optical trasnsceiver which consist of a laser transmitter and a receiver to provide full duplex (bi -directional) capability.

Wireless or optical

FSO is clearly an optical technology and not a wireless technology for two primary reasons:

• It enables optical transmission at speeds of up to 2.5 Gbps and in the future 10 Gbps u using WDM.
• Also, it obviates the need to buy expensive spectrum, which distinguishes it clearly from fixed wireless technologies.

Challenges

FSO is also a line-of-site technology and interconnecting points must br free from physical obstruction and able “see” each other. Rain and snow have little effect on FSO, however, the major challenge to FSO communication is fog. The primary way to counter fog when deploying FSO is through a network design that shortens FSO link distances and adds network redundancies.

Safety

With FSO, safety is often a concern because the technology uses lasers for transmission.
Two of the major concerns include human exposure to laser beams (which present much more danger to the eyes than any other part of the human body) and high voltages within the laser systems and their power supplies. Standards have been set for laser safety and performance. FSO systems comply with these standards