Cost-effective optical transponders for deployed metropolitan area networks

Improving the performance of electronic and optoelectronic components has enabled the investigation of transmitting optical channels with data rates greater than 40 Gb/s, over infrastructures that were initially supporting 10 Gb/s transport. However, for transporting high capacity channels, over long distances, considerable signal processing is necessary, with current emphasis being on digital techniques. Meanwhile in the context of optical networking where spectrally adjacent channels may cross different routes to interconnect the same source destination nodes, adaptive transmission systems become vital. This paper will suggest, compare and develop the necessary transponder technologies that enable transportation of 40 Gb/s channels over deployed Metropolitan Area optical Networks (MAN) infrastructure with emphasis on the interplay between realistic performance, feasibility and complexity/cost. Specifically it will investigate utilizing deployed optical infrastructure for transporting 40 Gb/s DQPSK channels in conjunction with various high performance, low complexity electronic equalizers that can compensate the corresponding linear impairment enhancement that accompanies this upgrade, namely Chromatic Dispersion and Polarization Mode Dispersion while they can be implemented in a single FPGA. It is shown that resource constraint performance evaluation is vital and the exact technology choice is related to the deployed infrastructure.