With core network traffic increasing at about 40% per year, service providers need a long haul transmission technology that will deliver scalable, cost-effective capacity without compromising on optical reach. The DWDM industry is now aligned on the fact that multi-carrier super-channels are the way to quickly access the spectral capacity that coherent transmission delivers in a way that will scale WDM without scaling operations.
Building super-channel line modules requires both electronics and optical technology functions. Infinera’s FlexCoherent Processor provides the electronics function, delivering the industry’s first shipping coherent electronic ASIC featuring software selectable modulation. Infinera’s third generation 500 Gb/s Photonic Integrated Circuit provides the optical technology in the super-channel implementation, integrating over 600 optical functions into a pair of small fingernail-sized chips.
Implementing Super-channels Without Large Scale PICsFor companies who do not have access to large scale photonic integration IP (intellectual property) they must use off the shelf optical components which consume more space and power than PICs – limiting single line card capacity to one long reach 100G channel using QPSK modulation. In order to get more throughput they must use higher order 16QAM modulation in order to increase that to 200 Gb/s on a single line card. Two of these optical circuits (on the same line card or separate line cards) are then combined together to create a 400 Gb/s, 16QAM super-channel. 16QAM has higher spectral efficiency but provides a dramatically shorter optical reach compared to QPSK limiting applicability to shorter metro networks.
Implementing Super-channels With Large Scale PICs
By implementing super-channel technology using large scale (i.e. multi-wavelength) photonic integrated circuit (PIC) technology, Infinera can deliver a range of benefits to our customers. The most obvious is that a single line card that is brought into service in a single operational cycle can now deliver five times the capacity compared to a typical 100Gb/s transponder, while still delivering exceptional long haul performance.
And with the reduction in complexity, implementing over 600 optical functions into one pair of transmit and receive PICs, systems become dramatically more reliable, with Infinera customers accumulating over 1.5 billion failure-free hours of PIC operation over the past ten years.
Finally, PIC economics allows Infinera to deliver super-channel capacity in a cash flow-efficient way using our unique Instant Bandwidth technology, by which a network operator can light up the entire super-channel with one set of wavelength planning, but can activate 100Gb/s slices using a software licensing mechanism.
|Type||Technology||Data Rate||Reach||No. of cards||Shipping|
|Alternate||Dual-card 16QAM||Discretes, Off-the-shelf||400Gb/s||~100s of km (typical ~1000 km)||2||2015|
|Infinera||Single-card QPSK||PICs||500Gb/s||~1000s of km (typical ~4000 km)||1||Since 2012|
Reach is estimated for terrestrial application based on real-world fiber and standard operational margins, not on labs conditions using specialized fiber.