Sayyad, P.; Rivas-Moscoso, J.; Klonidis, D.; Tomkos, I.; Shariati, M.; Comellas, J. IEEE International Conference on Communications p. 5192-5197 DOI: 10.1109/ICC.2015.7249148 Data de presentació: 2015-06-11 Presentació treball a congrés
Elastic optical network (EON) technology arises as a promising solution for future high-speed optical transport networks, inasmuch as it can provide superior flexibility and scalability in the spectrum allocation for seamlessly supporting a disparity of services, while coping with the rapid growth of Internet traffic. Spectrally efficient lightpath establishment in EONs is enabled by recent developments in flex-grid transceivers and wavelength selective switches (WSS), which are the key players in determining the amount of spectrum that needs to be reserved for a connection as well as the guard band (GB) required between adjacent channels, since the imperfect shape of the filters degrades the spectrum utilization efficiency of the network. In this paper, we focus on the impact of the filter sharpness on the performance of EONs from the networking perspective. In this regard, we initially quantify the effect of the sharpness of a transmitter Nyquist shaping filter and an LCoSbased WSS filter on the amount of spectrum required for efficient connection establishment. Subsequently, we investigate the practicality of moving to finer frequency slot sizes and, based on extensive simulation results, evaluate the improvement in terms of network blocking probability that can be obtained by using sharper filters.
A heterodyne envelope (HE) receiver (RX) is investigated in the context of orthogonal frequency division multiplexing (OFDM) passive optical networks (PONs). Impacts of limited roll-off factor of shaping filter and required guard-band (GB) are studied through numerical simulations, showing that the Carrier to Signal Power Ratio (CSPR) value plays a significant role in the systems performance. For a QPSK system with 10 Gbps bitrate and for a bit error ratio (BER) quality threshold of 10-3 we show an improvement of 10.8 dB in sensitivity and 25% in spectral efficiency by using an optimum CSPR value as compared to unity CSPR.