The Optical Internetworking Forum (OIF) says it will launch a program to develop specifications for what it calls an Integrated Dual Polarization Quadrature Modulated Transmitter Assembly (ITXA). The ITXA effort aims to define a common electrical interface that allows the inclusion of other modulator technology that could enable lower cost and smaller transmitter assembly size.
The effort responds to concerns that transmission technology based on the current dual-polarization quadrature phase-shift keying (DP-QPSK) with coherent detection specifications within the OIF’s long-haul DWDM implementation agreements may be too costly for metro and high-density applications. In fact, some systems houses have already announced their intention to pursue other 100-Gbps modulation schemes for such applications (see “ADVA Optical Networking offers cost-reduced 100-Gbps for metro networks”).
“Our existing Polarization Multiplexed Quadrature Modulated Transmitter has been successfully adopted in ultra long haul and metro markets,” said Karl Gass, the OIF’s Physical and Link Layer Working Group vice-chair and a consultant of TriQuint Semiconductor. “This companion project will address cost and performance trade-offs necessary to open higher volume applications.”