FREE SPACE OPTICS

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ABSTRACT

This paper deals with communication through optics using one of the latest technologies called the free space optics (FSO).FSO may sound new and experimental but in fact it predates optical fiber and has its roots in wartime efforts to develop secure communication systems that did not require cable and could withstand radio jamming.As a commercial communications technology, FSO has been around for more than a decade, but it is only recently that interest in this technology has started to grow. It was only recently developed for use in metropolitan area networks. The technology has its roots in military applications that reach back as far as the 1940s.

It was not until the 1960s, however, that the first significant FSO technology advancements began to occur in the United States, Europe and Middle East, where military researchers, engineers and technicians applied the use of infrared lasers in communications devices with the aim of providing secure data and voice transmission that would not be susceptible to “jamming” of radio frequency-based communications systems.

These early FSO systems were capable of transmitting merely a handful of kilobits over the air, but the advent of the Internet and its impact on telecommunications was decades away. In fact, European researchers of FSO systems in the 1960s experimented with ways to send FSO signals through both underground and underwater pipes, seeking to bend the invisible light beams with mirrors where a straight line-of-site could not be established.