Modular Multiformat Interfacing: The Building Blocks Of An Efficient Fibre Infrastructure

As video-distribution systems become more complex and the number of potential interfaces continues to grow, system designers need easier, more affordable ways to create all manner of fibre connections and topographies, writes by Paul McCann, Bluebell Opticom Managing Director.

In the ideal scenario, a few basic cards would serve as the foundation for a versatile, scalable infrastructure that could morph, expand, and contract to suit the application.

Bluebell Opticom products are designed to do just that. Bluebell offers a standard series of cards that can be used as the building blocks for scalable networks of any size and degree of complexity – from simple point-to-point links to large-scale fibre infrastructures. All of the cards do similar jobs, but they have varying degrees of flexibility. By adding components such as switches, splitters, and distribution amplifiers, system designers can create different topographies that change the size and capabilities of the network. At the same time, swappable SFP modules make it easy to accommodate various interfaces.

Bluebell's BC Series cards are compact, rack-mountable multiformat converters for use with a wide range of broadcast video and audio signals. They can perform an array of functions, from distribution and format conversion to monitoring and wavelength management (including CWDM). Such a wide range of functionality makes each card both a toolkit for systems engineers and a high-quality converter for any fixed installation.

The cards are designed to work with SFP modules, which provide a relatively inexpensive, universal way to make the card serve whatever function is needed in a given situation. You can adapt the functionality of the unit to suit different applications simply by switching to a different SFP converter module. This feature enables flexibility in both system design and on-site reconfiguration. Signal input and output formats are defined by selecting appropriate standard SFPs that can perform optical and/or electrical format conversions.

Multiformat SFPs can convert to and from composite, HDMI, DVI, optical, and 3G-SDI. They can also be used to convert optical signals from multimode to single-mode, repeat optical signals, or remap wavelengths within existing fibre systems. These cards accommodate MSA and non-MSA SFPs and, unlike cards from some other manufacturers, are not limited to transceivers. Figure 1 depicts how one Bluebell card, the BC363, can support any of five different input types and seven different output types simply by changing the SFPs.

By mixing and matching Bluebell's multiformat converter cards with other Bluebell components, system designers can accommodate an almost unlimited number of scenarios. Here are a few examples:

Ethernet Fibre Solutions
In one application, a London postproduction house uses a system of BC368 cards and SFPs to link Ethernet switches by converting optical signals between multimode and singlemode, thereby equalizing the fibre mis-match and ensuring everything can operate harmoniously on the same fibre infrastructure. At the same time, the combination of cards and SFPs increases the company's Ethernet data rates up to 10 gigabits per second.

Distribution
In another use case, BC364 and BC363 cards are used to generate a monitoring and distribution solution. Using the cards in combination with Bluebell splitters, optical switches, and distribution amplifiers creates diverse routing and switching capabilities. The distribution amplifier automatically senses the incoming signal and equalizes it before driving it into five available outputs, while optical switches sense the light levels of the inputs and automatically switch from a main to a backup path if the signal is lost. Such capabilities are critical for failover in the event of a breakdown in the transmission path.

Optimising Fibres
In its capacity as a CWDM manager, the BC364 takes in multiple optical signals and retransmits them at a wavelength that can be inserted into a CWDM mux. On the other end of the link, the signals are returned to their individual state. This functionality, coupled with the ShaxX technology, is what makes camera multiplexing possible. The BC364 becomes a multiplexer that can join up to 16 cameras and CCUs with ShaxX units over one pair of fibres.

Conclusion
A modular, multiformat interfacing approach goes a long way when it comes to creating flexible, cost-effective video distribution infrastructures. Individual cards might seem insignificant on their own, but the ability to mix and match them can make them the bedrock of a large and powerful system. Instead of an expensive conglomeration of external boxes and other single-purpose technology, media organizations get a versatile system that ensures harmony in the fibre network while saving money, time, and space.

Image: BC364 card

www.bluebellcomms.co.uk