Optical Wireless Solutions Based on Free Space Optical (FSO) Technology

Written by Lightpointe Communications


Amidrepparttar pervasive talk aboutrepparttar 139079 promises ofrepparttar 139080 information economy, it’s easy to overlookrepparttar 139081 logistical challenges of deliveringrepparttar 139082 necessary infrastructure to ensure everyone who wants connectivity is connected—regardless of where they live. Projected growth in customer demand for bandwidth will go wanting without connectivity, andrepparttar 139083 real challenge for fully realized networks is to create connections despiterepparttar 139084 very real physical and economic obstacles presented by today’s modern cities. The rewards for providing these connections arerepparttar 139085 likelihood of recouping previous investments inrepparttar 139086 fiber-optics network core/backbone—and establishing customer reliance on high-bandwidth networks for continued economic growth.

At one point, many telecommunications industry leaders and technology observers dreamed of all-fiber networks. But this vision is impractical for several reasons. The process of laying fiber in cities is time-consuming and often prohibitively expensive. Ongoing preservation and restoration of fiber-optic systems inrepparttar 139087 event of accidental disruptions or natural disasters is also time-consuming and technically challenging, as service providers must addressrepparttar 139088 concerns of bandwidth dependent customers frustrated with every hour of lost network access.

That having been said, all-optical fiber-optic networks—with their high-bandwidth capacities—are promising. Still, a world complete with fiber connections for all is decades from reality.

Deciding how best to complete high-bandwidth connections across networks is one ofrepparttar 139089 great quandaries ofrepparttar 139090 information age, and choosing which technologies to deploy to complete network connections will depend on costs and reliability(1) A combination of high-capacity access technologies providesrepparttar 139091 most cost efficient and reliable solutions for addressing both primary connections and backhaul. For all-optical networks, fiber optics and optical wireless solutions arerepparttar 139092 only two technology choices.

(1) Source: Free Space Optics, Merrill Lynch Global Securities and Economics Group, 15 May 2001

Parallel Histories

It may seem to telecommunications carriers and industry analysts that FSO technology only recently appeared, like a beam of light, torepparttar 139093 optical communications landscape. But FSO is only new in one respect: as a market proven technology for optical wireless solutions that provide customer connectivity in private and public networks spanning more than 60 countries.

FSO technology itself is older than fiber optics. Technically, optical communications includes all forms of communications using light, including mirror signals and lighthouses, offering a rich and storied history.

The electrically powered optical technologies referred to byrepparttar 139094 term “optical” or “electro-optical” began withrepparttar 139095 introduction ofrepparttar 139096 laser in 1960, which enabledrepparttar 139097 transmission of digital information as pulses of light.


Recent developments in FSO technology target telecommunications improvements for Metropolitan Area Networks (MANs), butrepparttar 139098 technology has its roots in government applications dating back to World War I when military units and covert agencies needed secure communication systems that did not require cable and could withstand intentional interference, also known as “radio jamming”. Portability of these early FSO devices was a hallmark and made them particularly valuable to military personnel who needed secure communications equipment that was simple to set up, transmit information and move from location to location. Additional optical communications developments occurred during World War II, and post-war economic restructuring led to further telecommunications technology progress. While electronics innovations such asrepparttar 139099 transistor and integrated circuits enabled post-war telecommunications progress,repparttar 139100 laser’s launching of electro-optical communication fueled research and development of advanced optical communications usingrepparttar 139101 only medium for laser transmission available then to military and aerospace industry physicists:repparttar 139102 atmosphere, or “free space,” hencerepparttar 139103 term free-space optics. Research and application of free-space optics continues to thrive inrepparttar 139104 aerospace industry to this day for applications beyond commercial and private telecommunications networks. Today’s commercially deployed optical wireless solutions arerepparttar 139105 result of a culmination of FSO technology advancements.


After 1970,repparttar 139106 introduction ofrepparttar 139107 fiber-optic cable as optical transmitter—along withrepparttar 139108 establishment of digital technology—combined to usher in a worldwide telecommunications revolution. Key among fiber’s attributes is its immunity to electrical interference (no electricity is run throughrepparttar 139109 fibers, so fiber signals do not interfere with each other); therefore, fiber can be run in areas without regard to interference from electrical equipment. Other benefits of fiber are:

• Security. It is resistant to taps and doesn’t emit electromagnetic signals.

• Compact size. Less duct space is required for these hair-strand sized fibers.

• High-bandwidth capabilities and low attenuation. Less fading or weakening of signals occur over long distances, which means fewer amplifiers are needed to boostrepparttar 139110 optical signals.

Given these advantages, fiber-optic cable heldrepparttar 139111 promise of revolutionizingrepparttar 139112 telecommunications sector, which was eager to buildrepparttar 139113 initial fiber networks.2 The first practical fiber systems were deployed byrepparttar 139114 telephone industry in 1977 and consisted of multimode fiber. Single-mode fiber, a more recent development, was first installed by MCI in a long-haul network system that went into service in 1983.3 The result of fiber-optic cable deployment is an extensive network of fiber crisscrossingrepparttar 139115 land. Duringrepparttar 139116 1990s,repparttar 139117 telecommunications network capacities grew nearly 10 times as much asrepparttar 139118 traffic itself, with most ofrepparttar 139119 bandwidth concentrated in dark fibers alongrepparttar 139120 network backbone often inaccessible torepparttar 139121 end-user.5 The massive investment to put optical capacity inrepparttar 139122 long-haul telecommunications network backbone looks relatively simple compared with today’s metropolitan network challenges.

Beginning in 2000, carriers intensified their focus to building fiber-optic cable connections betweenrepparttar 139123 United States’ 25 largest metropolitan areas torepparttar 139124 nation’s long haul backbone networks. This network gap is often calledrepparttar 139125 “last mile,” where only 7 percent to 10 percent of end-users have access to fiber. “Routes in cities typically run to incumbent telephone company central offices and carrier hotels, which often are clustered together inrepparttar 139126 same areas, frequently near AT&T’s switches.

From there, they have runs to customers, data centers, Internet service providers and application service providers.”5 While this network configuration sounds relatively simple,repparttar 139127 logistics of laying fiber connections in metropolitan areas are quite complicated and time-consuming. The expense of construction and right-of-way permits for laying fiber often amounts to 20 percent ofrepparttar 139128 cost of building fiber routes for networks. Moreover,repparttar 139129 convoluted process of obtaining permits can delay projects for 12 months to 16 months or longer. Metropolitan landscapes, with their busy streets, politically powerful neighborhoods, historic districts, and public works bureaucracies makerepparttar 139130 permit process more complex to navigate than those in suburban and rural long-haul network routes.6 Time delays can be created by municipal public works departments whose staff members feel a responsibility to protect public investments in road surfaces, water mains and gas lines, plus quality of life concerns regarding noise, dust and traffic disruption during construction projects to lay fiber.

Digital Signage - Choosing the Best Video Distribution Technology

Written by Minicom Advanced Systems

Digital Signage: An Overview Digital signage isrepparttar use of digitally powered signs (such as plasma display panels, liquid crystal displays (LCDs), kiosk stations, computer monitors and normal televisions) to replace and enhance traditional media. Digital signage is revolutionizingrepparttar 139078 media and information industries by allowingrepparttar 139079 central and rapid update of content and its immediate delivery to specific audiences in specific locations.

Components of Digital Signage The components needed for a digital signage system include:

An authoring console, equipped with content management software, allowingrepparttar 139080 definition of content in a variety of playback formats.

A server, to which finished content is uploaded and from where it is distributed to different displays inrepparttar 139081 network.

A distribution infrastructure, consisting of a data network or fiber optic or CAT5 cable, which broadcasts media fromrepparttar 139082 server torepparttar 139083 displays.

Digital signage displays, which can be plasma displays, LCD monitors, CRT monitors, or kiosk stations.

Benefits of Digital Signage Digital signs have already brought significant benefits to businesses and media vendors alike:

Attention grabbing advertising A digital sign brings innovation and movement to previously static media locations, and hasrepparttar 139084 power to get customers' attention, making it a particularly effective form of advertising.

Real-time advertising and information Digital signage allows advertising and information to be updated onrepparttar 139085 fly from one remote authoring station and broadcast immediately to audiences regardless of location.

Relevant audiences With digital signage, advertising focuses onrepparttar 139086 best potential customer: an existing one. Supermarkets have already found that current customers are more likely to purchase products advertised on their digital signs. Cost savings Every time digital signage users change their message or campaign, they save on printing costs and processing time. Profit center opportunities Businesses can create instant profit centers by selling advertising time on their digital signs to customers or suppliers.

DIGITAL SIGNAGE Uses of Digital Signage It is not surprising that, with allrepparttar 139087 benefits of digital signage, there are so many uses for it worldwide. They include: Advertising networks In-store advertising Interactive kiosks Tradeshow displays Corporate identity branding Electronic menus and lobby displays Branch office communication Campus bulletin boards Community bulletin boards Arrival and departure schedules Franchise communication systems Emergency announcement systems Corporate communication systems Back office employee training

Digital Signage Distribution Technology: “What Lies Beneath” When considering a digital signage project, users usually focus on display types and content management software. Forrepparttar 139088 integrator, however, there is an important component thatrepparttar 139089 user rarely considers:repparttar 139090 distribution technology and platform. This infrastructure transmitsrepparttar 139091 digital video and audio fromrepparttar 139092 server torepparttar 139093 appropriate displays, and is a key contributor to actual digital signage performance. In addition, asrepparttar 139094 connecting component for all displays,repparttar 139095 distribution technology can be a significant part ofrepparttar 139096 project budget. That’s why choosingrepparttar 139097 correct distribution technology is vital in ensuring a successful digital signage installation. Options for Digital Signage Distribution

There are three main options for digital signage distribution:

Data network Fiber-optic cable CAT5 cable

In this paper, these options will be presented together withrepparttar 139098 core considerations in choosing a distribution technology:

Cost Performance Existing infrastructure

Digital Signage Distribution Options: Platforms & Combinations

Each platform has its own benefits and drawbacks. When harnessing more than one platform. There are a number of interesting combinations as discussed below.

Data Network Platform A data network platform uses a computer network infrastructure in order to transmit content inrepparttar 139099 form of compressed multi-media files (such as MPEG files) fromrepparttar 139100 management station torepparttar 139101 central server and from there torepparttar 139102 computer connected torepparttar 139103 display device. The central server handles distribution to multiple displays, andrepparttar 139104 display-end computer decompressesrepparttar 139105 file for display onrepparttar 139106 display device. Alternatively, if only one display is required,repparttar 139107 network can transmitrepparttar 139108 compressed file directly fromrepparttar 139109 management station torepparttar 139110 display-end computer, which then decompresses and displaysrepparttar 139111 file.

Benefits & Drawbacks The advisability of data networks depends largely on existing infrastructure. If there is an existing computer network infrastructure, using a data network platform for digital signage can save costs significantly. However, if no computer network already exists,repparttar 139112 need to implement such an infrastructure will increase costs considerably.

An additional cost related to data networks is caused byrepparttar 139113 need for display devices to be connected to local computers or equipped with embedded CPUs, resulting in extra investment in hardware, an important factor when costingrepparttar 139114 project as a whole.

In addition, from a performance standpoint, using a data network platform has several disadvantages. A data network platform limitsrepparttar 139115 user torepparttar 139116 compression technologies available onrepparttar 139117 market today, technologies that significantly downgraderepparttar 139118 quality ofrepparttar 139119 multimedia content andrepparttar 139120 displays’ dependence onrepparttar 139121 network is another major consideration for 24x7 locales that cannot tolerate display downtime.

Fiber Optic Extenders Fiber optic cable is a transmission medium favored for applications that need high bandwidth, long distances, and complete immunity to electrical interference. That makes it ideal for digital signage, which requires high resolution and transmission over long distances. Unlike network platforms, fiber optic cable does not require CPUs or special software atrepparttar 139122 display end. All that is required is a transmitter and receiving unit for each display.

There are two options for fiber-optic cable: single mode or multi-mode. Single-mode fiber provides a higher transmission rate and up to fifty times more distance than multimode, but it also costs more. In general,repparttar 139123 decision between different types of fiber should berepparttar 139124 result of a simple cost-benefit evaluation:repparttar 139125 distance and level of resolution or performance required versusrepparttar 139126 acceptable investment in distribution technology.

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