SEPTEMBER 24, 2008 By Meghan Fuller Hanna -- This week at the European Conference on Optical Communications (ECOC) in Brussels, JDSU (search for JDSU) announced its photonic integrated amplifier (PIA) platform, which brings both photonic integration and reconfigurability to the optical amplifier space.
On the photonic integration side, JDSU says it can take up to 50 discrete, passive components and integrate them all on a single chip. "By doing that, we get all the benefits of functional integration," explains Craig Iwata, senior director of marketing and business operations at JDSU. "It's easier for us to manufacture, it's lower in cost, and it's actually higher in performance because we don't have to deal with multiple splices of fiber and individual components."
However, not all the components can be integrated onto the chip. Isolators, for example, must be discrete, but JDSU says it has taken the six individual, discrete isolators found on a typical amplifier and combined them into a single integrated isolator that acts as one component. The company then takes this integrated isolator and edge mounts it onto the PLC chip within the PIA platform; as a result, it functions seamlessly with the integrated optical amplifier elements on the chip. Performance is improved because the signal does not have to travel on and off the chip through separate isolators.
In addition, new waveguide technology simplifies the routing, splitting, and recombining of light signals within the PIA, says the company. Typical PLCs support only one wavelength of light, but amplifiers require two: The 1550-nm signal itself and the 980-nm light that is used to boost the 1550-nm signal. JDSU has developed a new waveguide technology that enables a single PLC to support both the 980- and 1550-nm signals.
That said, photonic integration is only half the story. According to JDSU, the PIA platform is also the industry's first reconfigurable optical amplifier. In other words, the same PIA could be software-configured for use as a pre-amplifier at receiver sites, as a booster amplifier at transmit locations, and as an inline amplifier between locations that transmit and receive optical signals with a network. As a result, service providers or network equipment manufacturers (NEMs) will require fewer products in inventory, and they will have more flexibility in their deployment options.
"The reconfigurability aspect allows us to fine tune the performance, which means our amplifier would have a better noise figure--essentially, it would have less noise," Iwata explains. "The benefit that less noise has to a network would be longer reach. We believe it's up to 15% to 35% longer distance before you would have to do a regen[eration]," Iwata explains. "And in a DWDM network, that regen[eration] or OEO is a cost."
The company says the reconfigurability of its amplifier is the result of three components:
• Variable pump splitter. This component provides improved noise performance over a wider dynamic range by allowing a single amplifier to be tuned to accommodate both low and high input applications, greatly improving the noise figure at low input conditions.
• Tunable gain flattening filter. When used with an optical channel monitor, it can actively compensate for common system link impairments, such as unequal channel power levelsÂ caused by transmission fiber and by other components. This allows the amplifier to provide output with consistent power levels for each channel amplified.
• Tilt filter. The tilt filter provides more predictability in amplifier performance with an active tilt adjustment when a channel load or total signal power changes. It is more linear than current alternatives, says the company, and more closely matches typical network characteristics.
"Until now, the basic technology for optical amplifiers hadn't changed significantly over the past decade," notes Jy Bhardwaj, vice president and general manager of agile optical networks in JDSU's Optical Communications Business Segment. "JDSU has leveraged its functional integration approach at the photonic level to create the new PIA platform. It opens the door for JDSU and its customers to think of new ways to apply the solution and add even more functionality."
The PIA platform, which JDSU says will be sold as an amplifier module as well as an integrated function within its AON Super Transport Blade, is currently sampling with customers and will be available in 2009.