NASHUA, NH-Developed in the 1960s for military and aerospace applications, free-space optics (FSO) has had limited success in the commercial sector. Potential users have had a hard time overcoming the perception that technical issues-primarily range limitations and atmospheric interruptions such as fog-make FSO unreliable or overly expensive.
But this scenario is changing. The technology has matured, safety standards are in place, and the push for greater broadband access by consumers and better network security for government applications is spurring broader adoption of FSO. Applications and markets for the technology, along with the technology itself, are continuing to develop, as evidenced in the variety of market and technology approaches taken by different system vendors.
Bob Preston, senior vice president and chief marketing officer at Lightpointe (San Diego, CA), points out that for point-to-point communications in general, whether wireless or wired, users ultimately need to find an optimal three-way tradeoff among distance, bandwidth, and availability to suit any given application. FSO offers high bandwidth of course, and earlier this month, Lightpointe moved to boost availability in its product line for the enterprise market by introducing an integrated FSO-radio frequency (RF) system.
The size of the enterprise market (outdoor point-to-point connections over 500- to 1500-meter distances) was about $100 million in 2004 and is projected to hit $165 million this year, according to Preston. By boosting availability (uptime percentage) from 99.9% with FSO alone to 99.999% with a combination of FSO and RF, the company hopes to extend the enterprise market potential out to what they call a short haul-high capacity market segment, estimated at $352 million last year and projected to climb through $439 million this year to reach $669 million by 2007.
The recently introduced Lightpointe system (FlightStrata 100 XA) uses a series of algorithms to monitor performance thresholds automatically and to transfer traffic instantaneously from the primary FSO to the active-standby secondary path (a license-free 5.8-GHz RF transmitter) to maintain network availability, when thick fog, for instance, obstructs the FSO line of sight.
New strategic initiatives at fSONA (Washington, DC) this year include a physical move into fuller engagement with the US military and federal market and a broadening of market offerings through a distribution agreement with LaserBit (Budapest, Hungary). CEO Sunny Taylor, former VP of North American sales at fSONA with a particular focus on US military and federal accounts, moved into the CEO position about a month before announcing a relocation of corporate headquarters from British Columbia, Canada, to Northern Virginia, and the appointment of defense sector veteran, Samuel D. Wyman III to chair the fSONA Board of Directors at the end of April.
“We feel there is a great opportunity for fSONA to serve the military and homeland security efforts,” Taylor said. “For military customers, our SONAbeam systems are ideal for distributing bandwidth throughout a base or campus at a fraction of the cost of fiber. For federal customers, SONAbeam can aggregate real-time digital video surveillance feeds to a central point for monitoring and processing.”
Taylor emphasized that fSONA is not moving away from its commercial customer base, however, and the company announced a bilateral distribution agreement early last month with LaserBit (Hungary) that allows both companies to sell their complete combined product portfolio globally. The products offered by the two companies will range from LaserBit’s low-cost Power over Ethernet (PoE) Pluto solutions to fSONA’s military-grade, high-performance SONAbeam M Series.
fSONA’s product-line tends toward the higher-end of the market because of the use of 1550-nm wavelength lasers, yielding a significant eye-safety benefit over commonly used 750 to 900-nm lasers according to product development manager Pablo Bandera (Lightpointe lasers operate at 400 to 700 nm). Since 1550-nm signals tend not to pass through the cornea to cause retinal damage, the systems can be operated at much higher (~50x) power levels, thereby providing advantages in penetrating poor visibility conditions such as fog and thus boosting FSO system availability percentages, as well as potentially longer distances and higher data rates.
Both fSONA and Lightpointe use multiple beams in their high-end systems to average out the effects of atmospheric scintillation due to heated air rising from the earth or man-made devices such as heating ducts, which can create temperature variations among different air pockets and cause fluctuations in signal amplitude. Aoptix (Campbell, CA) uses adaptive optics technology to control this problem in an FSO product intended to provide a seamless extension of the military Global Information Grid that connects military or government assets directly into a battle space. Ongoing research at a number of sites is focused on bringing the cost of adaptive optics technology more into line with commercial needs, and if and when that is accomplished, adaptive optics may eventually become a preferred mode of scintillation control for commercial FSO systems.
-Hassaun A. Jones-Bey