121 research outputs found

    Long Wavelength VCSELs Exploitation for Low-Cost and Low-Power Consumption Metro and Access Networks

    Get PDF
    Long wavelength VCSELs are demonstrated to be able to support metro and access networks in order to achieve low-cost and low-power consumption transceivers. In particular, the exploitation of discrete multitone (DMT) direct modulation allows to achieve high transmission capacities and the availability of widely tuneable MEMS-VCSELs to sustain agility, reconfigurability and colourless features of networks

    Optical sensing in urban areas by deployed telecommunication fiber networks

    Get PDF
    The telecommunication fiber network already deployed in urban areas provides an added value to the optical asset itself, allowing a smart monitoring of our cities in a large scale. It is possible to use deployed PON infrastructures for structural vibration and local seismologic perturbations monitoring. On the other hand, surveillance of the embedded network and real-time safety diagnostic is also possible. The invited talk will present different experimental demonstrations to show the sensing performance by exploiting deployed fiber links, assessing the compatibility with the optical data telecom traffic at very high rate

    Radio-over-modes for C-RAN architecture with smart optical resources assignment

    Get PDF
    In this paper we consider a centralized radio access network (C-RAN) architecture with a fully analog fronthaul link between remote radio heads (RRHs) and baseband units (BBUs) based on the radio over fiber (RoF) paradigm. Mode division multiplexing (MDM) and frequency division multiplexing (FDM) are employed to provide an additional multiplexing signal dimension to meet the huge bandwidth requirements of next generation (5G) wireless mobile systems. The main contribution of the paper is to prove that a smart resource assignment between the radio antennas and the mode/frequency dimensions allows the communication over the RRH-BBU link at rates that are comparable to those achieved by an ideal fronthauling where BBU and RRH are assumed to be co-located, even without any complex and costly optical equalization technique. Validation is on the radio-link capabilities employing multiple antennas to meet the demand for massive MIMO technology

    Transceivers and Spectrum Usage Minimization in Few-Mode Optical Networks

    Get PDF
    Metro-area networks are likely to create the right conditions for the deployment of few-mode transmission (FMT) due to limited metro distances and rapidly increasing metro traffic. To address the new network design problems arising with the adoption of FMT, integer linear programming (ILP) formulations have already been developed to optimally assign modulation formats, baud rates, and transmission modes to lightpaths, but these formulations lack scalability, especially when they incorporate accurate constraints to capture inter-modal coupling. In this paper, we propose a heuristic approach for the routing, modulation format, baud rate and spectrum allocation in FMT networks with arbitrary topology, accounting for inter-modal coupling and for distance-adaptive reaches of few-mode (specifically, up to five modes) signals generated by either full multi-in multi-out (MIMO) or low-complexity MIMO transceivers and for two different switching scenarios (i.e., spatial full-joint and fractional-joint switching). In our illustrative numerical analysis, we first confirm the quasi-optimality of our heuristic by comparing it to the optimal ILP solutions, and then we use our heuristic to identify which switching scenario and FMT transceiver technology minimize spectrum occupation and transceiver costs, depending on the relative costs of transceiver equipment and dark fiber leasing

    Beyond 25 Gb/s Directly-Modulated Widely Tunable VCSEL for Next Generation Access Network

    Get PDF
    We demonstrate capacities beyond 25Gb/s up to 40 km in the whole C-band range without any dispersion compensation by DMT direct modulation and direct detection exploiting widely tuneable MEMS-VCSELs for future low-cost high-capacity access networks

    DEMONSTRATION OF STRUCTURAL VIBRATION SENSING OVER A DEPLOYED PON INFRASTRUCTURE

    Get PDF
    We demonstrate the possibility of using a deployed Passive Optical Network (PON) infrastructure for structural vibration monitoring for smart city applications and simultaneously downstream 10Gbit NRZ transmission. The impact of PON trunk fibre backscattering noise on sensing system performance is experimentally assessed

    Impact of SOA-Based Add-Drop Switch Nodes on High-Capacity Multicarrier Transmission for Metro-Access Networks

    Get PDF
    Internet-generated traffic growth is forcing the development of new low-cost solutions in metropolitan area networks (MANs), in particular in the transceiver and network node architectures. Semiconductor optical amplifier (SOA)-based wavelength blockers can be used as fundamental building blocks to add and drop optical channels in the node architecture of several network hierarchical levels. Even if its employment is advantageous in terms of costs and amplification bandwidth, the SOA can operate in a nonlinear regime. This work analyzes the impact of SOA-based node crossing on high-capacity discrete multitone (DMT) signals. In order to properly evaluate the interplay between optical channels and SOA self-gain modulation, both external and direct modulations are considered. Dual-sideband (DSB) and single-sideband (SSB) DMT variants are taken into account, showing no significant difference in the impact of SOA crossing for external modulation of a DFB laser. On the other hand, an important effect of subcarrier suppression arises on DSB DMT direct modulation of a vertical cavity surface emitting laser (VCSEL), less consistent for SSB DMT direct modulation. The analysis allowed to properly choose the bias current for the SOA employed in an experimental setup used to evaluate the transmission performance in a MAN scenario including add-drop lossless switch nodes. The experimental results demonstrate that a target capacity of more than 50 Gb/s per channel can be achieved in a 116-km MAN network composed of an SOA-based metro-access node and two metro-core aggregators, considering the transmission of three 25-GHzspaced DMT channels.</p

    Impact of SOA-Based Add-Drop Switch Nodes on High-Capacity Multicarrier Transmission for Metro-Access Networks

    Get PDF
    Internet-generated traffic growth is forcing the development of new low-cost solutions in metropolitan area networks (MANs), in particular in the transceiver and network node architectures. Semiconductor optical amplifier (SOA)-based wavelength blockers can be used as fundamental building blocks to add and drop optical channels in the node architecture of several network hierarchical levels. Even if its employment is advantageous in terms of costs and amplification bandwidth, the SOA can operate in a nonlinear regime. This work analyzes the impact of SOA-based node crossing on high-capacity discrete multitone (DMT) signals. In order to properly evaluate the interplay between optical channels and SOA self-gain modulation, both external and direct modulations are considered. Dual-sideband (DSB) and single-sideband (SSB) DMT variants are taken into account, showing no significant difference in the impact of SOA crossing for external modulation of a DFB laser. On the other hand, an important effect of subcarrier suppression arises on DSB DMT direct modulation of a vertical cavity surface emitting laser (VCSEL), less consistent for SSB DMT direct modulation. The analysis allowed to properly choose the bias current for the SOA employed in an experimental setup used to evaluate the transmission performance in a MAN scenario including add-drop lossless switch nodes. The experimental results demonstrate that a target capacity of more than 50 Gb/s per channel can be achieved in a 116-km MAN network composed of an SOA-based metro-access node and two metro-core aggregators, considering the transmission of three 25-GHzspaced DMT channels.</p
    • …
    corecore