fibresystems.org blog

« Carrier Ethernet grows up | Main | An inconvenient technology »

ECOC: From the show floor

Components vendors are out to prove that Infinera is not the only game in town when it comes to photonic integrated circuits (PICs). At the European Conference on Optical Communications (ECOC) there are a couple of demos worth pointing out.

First up, tunable laser maker Santur is showing a 100 Gbit/s PIC made out of indium phosphide. The device is a variation on the company’s tunable laser technology, which contains an array of 10 lasers with a MEMS device to select the output from one of them. In the 100 Gbit/s PIC, the MEMS device has been replaced by a passive multiplexer, which combines the light from all the 10 Gbit/s lasers (running at the same time) onto a single fibre.

The company claims that its device offers a simple solution for distances up to 10 km, in access networks and short reach interconnects. It could potentially be cheaper than the 4x25 Gbit/s or parallel optics schemes that are also being considered for 100 Gbit/s applications.

But Centre for Integrated Photonics (CIP), the former research activity of BT, has gone one better with a demonstration of a 32-channel PIC.

CIP’s photonic integration technology, which was unveiled here at the show is based on hybrid integration platform called HyBoard. Indium phosphide active components are mounted onto silicon “daughterboards”, which are then flip-chip mounted onto a silica-on-silicon motherboard containing optical waveguides to connect all the components. The platform is self-aligning, and has been designed so that it can be outsourced to a contract manufacturer if volumes require it.

CIP’s demonstration, which contains continuous-wave (CW) lasers, showed how the channels could be turned on and off individually, how the power could be balanced across the channels, or tilted to suit the input to an optical amplifer. Inside the package are two monolithically-integrated arrays of 16 lasers each, mounted side-by-side on the HyBoard platform.

The PIC in its current form is intended for WDM-PON, where it could provide a colourless solution for customer premise equipment (CPE). In this application, an array of CW lasers located at the headend sends light down the fibre to the CPE, which contains a reflective SOA that puts the data onto the wavelength, and reflects it back up the fibre to the optical line terminal.

CIP says that the concept could be extended to create a 160 Gbit/s PIC, containing 16 channels at 10 Gbit/s, simply by adding modulators to the package.

Posted by Pauline Rigby on September 24, 2008 5:59 PM | Permalink