The Transporter - AvNetwork.com

The Transporter

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The demand for bandwidth continues to increase in our industry. Fiber optic systems provide a method for transporting multiple channels of bi-directional video, voice, and data with broadcast quality and fidelity over extremely long distances. Videoconferencing systems utilize various techniques for transmitting and receiving video, audio, and data. Traditional systems incorporate copper solutions that have provided adequate performance but can have significant limitations in both video and audio quality-particularly as the demand for higher resolution, real-time video continues to increase. As more information was added to the system, so to was video compression. The result is that the quality of the signals continued to deteriorate.

Fiber transmission systems, on the other hand, offer exceptional real-time video and audio quality whether the signals are standard composite or extend out to high resolution RGBHV, HDMI 1.3, and high performance HDSDI video signals. Corporate, government, military, and educational institutions are using more and more fiber for transporting multiple, bi-directional real-time video, audio, and data signals over a single fiber-ideal for high-quality videoconferencing applications.

Unlike copper, whose bandwidth decreases linearly with distance and has very limited distance capability at high data rates, the bandwidth of fiber provides an almost limitless capacity for transmitting many high-quality signals an almost unlimited distance. The norm for telecommunications is now 40Gbps systems. In fact, last November, Verizon reported transmitting live, real-time video in a 100Gbps system over a distance of 504 km (315 miles) between Miami and Tampa, FL. While still not commercially available, it does demonstrate the capability of fiber. This is equivalent to simultaneously transmitting 67 HDSDI, or 12,500 composite, real-time bi-directional video channels on one fiber. Needless to say, our videoconferencing bandwidth requirements fit very well into the capabilities of fiber.

Copper's saving grace is that of video compression. Video signals can be compressed to minimize bandwidth requirements and allow for more video and audio to be sent over longer distances. As we all know, compression results in lower video and audio quality. Traditional webcasts, for example, take advantage of this compression technique to provide adequate videoconferencing capabilities. However, as the demand for higher quality video continues to grow, these compression techniques become a limiting factor as the quality degrades and latency becomes an issue.

Wavelength multiplexing allows the user to combine literally hundreds of different types of bi-directional, real-time signals on one singlemode fiber. These signals can be a combination of composite, RGBHV, DVI, HDMI, HDSDI video, audio, and data. Only fiber provides this level of flexibility and versatility.

Just as different types of copper cables yield different bandwidths and, therefore, distance capabilities, multimode and singlemode fiber will provide different signal and distance characteristics. While distance for high bandwidth video transmission over copper is measured in feet or meters, distances over fiber are measured in kilometers for multimode fiber and tens of kilometers on singlemode fiber. Unlike copper, whose signal quality degrades linearly with distance, the signal quality over fiber stays high and constant over the entire length of fiber.

It's important to keep in mind that, unlike copper, fiber allows for a large variety of low and high performance signals to be sent simultaneously over one fiber in two directions. Other fiber system architectures yet to be discussed include routing, protection switching, and distribution of signals. As the demand for higher quality, more complex, longer distance videoconferencing systems continues to grow, fiber will be an important factor in providing the transport gateway for these signals as well as versatile system architectures-thus "future-proofing" your infrastructure investment.

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