Neophotonics introduces passive PIC-based products

The company expects the products to become key enablers of the emerging 'coherent' optical network transmission systems for 40Gbps and 100Gbps networks.

Coherent signalling technology allows the first 40Gbps and then the 100Gbps to be transmitted over DWDM channels currently transmitting 10Gbps.

The Neophotonics coherent mixer and differential quatenary phase shift key (DQPSK) demodulator products provide for transparent-phase decoding within each of the two major branches of coherent transmission systems emerging for 40GBps and 100Gbps.

The Neophotonics coherent mixer is an optical demodulator providing advanced demodulation to analyse the state of polarisation and the optical phase of a phase-modulated signal relative to an externally supplied optical reference.

This is claimed to enable recovery of the phase-polarisation constellation for dual-polarisation quatenary phase shift keyed (DP-QPSK) data transmission.

The Neophotonics coherent mixer requires no power, operates across the C or L band and is based on planar integration, utilising lower-cost, high-volume semiconductor production methodologies.

At the same time, Neophotonics announced the release of an additional demodulator product for DQPSK data transmission.

DQPSK systems utilise delay-line interferometers (DLIs) to coherently mix the incoming signal with a delayed sample, thereby avoiding the need for an external optical reference.

Neophotonics's DQPSK demodulator consists of two DLIs, providing in-phase and quadrature analysis of the phase-encoded signal.

To accommodate the unpredictable and varying nature of the received signal polarisation, the DQPSK demodulator has been optimised so that the performance exhibits extremely low sensitivity to polarisation variations, according to the company.

Tim Jenks, chairman and chief executive officer of Neophotonics, said: 'The rapid uptake of 40Gbps transmission on the line side and the anticipated move to 100Gbps in the next couple of years enable significantly greater utilisation of already-deployed DWDM channels, but at the same time places stringent requirements on the necessary optical components.' Ferris Lipscomb, vice-president of marketing for Neophotonics, said: 'These demodulators are precision assemblies of passive optical components and, since they are used on each channel rather than on each fibre, will be required in fairly large volumes with tightly maintained specifications.

'As such, they are ideal candidates for photonic integration and especially planar waveguide integration,' he added.

Neophotonics is showcasing its products at the OFC/NFOEC exhibition (Booth 1,126).

These include its portfolio of MEMS- and photonic integrated circuit (PIC)-based optical components, its line of telecom transceiver products in SFF, SFP and XFP form factors and its 40Gbps and 100Gbps coherent optical transmission systems.