Abstract-Architectural changes are required at the underlying networks to support the expected Internet data traffic volume growth caused by the popularization of cloud services, 5G-based services, and social networks, whereas providing a highly dynamic connectivity. Cost-effective and energy efficient solutions for flexible network subsystems are required in order to provide future sustainable networks. In this paper, we present a cost-effective DWDM ROADM design enabling optical Metro-Access networks convergence. The cost-effective DWDM ROADM capabilities have been also assessed in an ultra-Dense Wavelength Multiplexing (u-DWDM) Ring Network scenario. In particular, the achievable network throughput has been considered. Index Terms-DWDM; ROADM; Throughput. I. INTRODUCTIONhe ICT eco-system has been rapidly and dramatically changing in the last years. New multimedia and cloud services, the deployment of the Internet of Things (IoT) and the convergence between optical and wireless communications at the 5G paradigm [1] are requiring changes to the networks in order to enable scalable growth in traffic volume, while supporting a high level of dynamic connectivity, full flexibility and increased energy-efficiency. These features can be achieved by considering the cooperation between the network control and data planes. On the one hand, the management and control of networks are evolving towards a Software Defined Networking (SDN)-based centralized architecture (see Fig. 1 accomplished by the subdivision of a DWDM channel into smaller channels called frequency slots (FS) wherein the uplink (U) and the down-link (D) for each user can be established (see Fig. 1). This paper is divided into five sections. Section II presents the proposed cost-effective DWDM Reconfigurable Optical Add-Drop Multiplexer (ROADM) node design, its operation modes and the main advantages of the proposed ROADM architecture. Section III presents the insertion loss, sensitivity and crosstalk measurements and their experimental set-up used for the ROADM characterization. Section IV presents the considered u-DWDM network scenario for proving the cost-effective DWDM ROADM capabilities; an iterative process to design each costeffective DWDM ROADM is proposed in order to obtain the achievable network throughput.Finally, Section V completes the paper with the main conclusions. II. DWDM ROADM NODE ARCHITECTUREThe ROADM design for future Metro-Access converged Networks is basically driven by new network-level requirements, such as full flexibility, adaptability, scalability, resilience and increased energy-efficiency [5]. In order to reach all those features, a new cost-effective

The current constant growth in mobile networks' traffic demands caused by the popularisation of cloud and streaming services on personal devices, requires architectural changes so as to fulfil all new 5G mobile network requirements. Cloud access radio network (C-RAN) architecture in combination with the massive deployment of small cell antenna sites have recently been proposed as a promising solution but will be demanding for high capacity mobile fronthaul links. An efficient way for performing that connectivity is to make use of the dense wavelength multiplexing passive optical network (DWDM-PON) infrastructure. In this context, OFDM has been extensively explored as a potential candidate. Nevertheless, the main drawback of OFDM is its high out-of-band radiation. In order to overcome that drawback, new 5G multicarrier waveforms (FBMC, UFMC and GFDM) have recently been proposed. In this paper, we experimentally assess and compare 10Gbps 32-QAM-OFDM/FBMC/UFMC/GFDM system performance for high-layer split ultra-DWDM-PON-based fronthaul using a radio-over-fiber technique. The performance has been done in terms of spectral efficiency, peak-to-average power ratio, spectral density and receiver sensitivity. In particular, intensity-modulation with direct-detection and quasi-coherent-detection have been considered. In order to improve the multicarrier system energy efficiency, the effect of using a hard clipping technique over transmitted signals is also studied. Finally, we evaluated the crosstalk interference between two adjacent channels of the same modulation scheme, as a function of their electrical frequency span for downlink application.Index Terms-Filter-bank based multi-carrier, fronthaul, generalised frequency division multiplexing, orthogonal frequency division multiplexing, radio-over-fiber, universal filtered multicarrier.

No abstract

No abstract

No abstract