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Free Space Optics
What is FSO?
Free-Space Optics (FSO) is a line-of-sight technology that uses lasers to provide optical bandwidth connections. Currently, FSO is capable of up to 2.5 Gbps of data, voice and video communications through the air, allowing optical connectivity without requiring fiber-optic cable or securing spectrum licenses. FSO requires light, which can be focused by using either light emitting diodes (LEDs) or lasers (light amplification by stimulated emission of radiation). The use of lasers is a simple concept similar to optical transmissions using fiber-optic cables; the only difference is the medium. Light travels through air faster than it does through glass, so it is fair to classify FSO as optical communications at the speed of light.
FSO technology is relatively simple. It's based on connectivity between FSO units, each consisting of an optical transceiver with a laser transmitter and a receiver to provide full duplex (bi-directional) capability. Each FSO unit uses a high-power optical source (i.e. laser), plus a lens that transmits light through the atmosphere to another lens receiving the information. The receiving lens connects to a high-sensitivity receiver via optical fiber. FSO technology requires no spectrum licensing. FSO is easily upgradeable, and its open interfaces support equipment from a variety of vendors, which helps service providers protect their investment in embedded telecommunications infrastructures.