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Access infrastructure combining fiber optic and wireless technologies can provide the necessary broadband access required by convergence of wireless and wired networks. Optical millimetter-wave generation using up-conversion is considered as a cost-effective solution in radio over fiber systems. In this paper we discuss and compare the robustness against dispersion of three millimetter-wave generation...
Adaptation to changing conditions in the transmission medium is a particularly desired property in optically-routed networks due to their heterogeneous nature. Toward this goal, we propose in this paper rate-adaptive polarization multiplexed coded multilevel modulation schemes based on non-binary quasi-cyclic low-density parity-check (LDPC) codes and coherent detection. The proposed scheme can support...
Passive optical networks (PONs) are considered as a promising solution for broadband access networks. Due to the growing demand for reliable service delivery, fault management in the network is becoming very significant. However, there is a trade off between the cost of protection and the level of service reliability. Since economical aspects are most critical in the access part of the networks, improving...
In transparent WDM networks, the optical signal crosses several equipments (cross-connect, amplifiers and subfibers) and while the signal is propagated, the optical components causes their degradation. Thus, paths with low signal quality should be avoided, especially when the application requires quality of service (QoS). In this context, an appropriate allocation of resources requires encompassing...
In transparent wavelength routed optical networks, the signal quality degrades due to physical layer impairments. Certain physical effects make routing decisions made for one lightpath affect and be affected by the decisions for other lightpaths. To safely establish a lightpath for a new connection two main approaches can be used. The most common approach is to select a lightpath that has acceptable...
This paper discusses hybrid fiber optic access network architectures combining baseband wireline and mm-wave channels. We focus on mm-wave radio over fiber (RoF) optical access network architectures which combine radio subcarrier multiplexing techniques to improve system efficiency with fiber dispersion mitigation provided by optical single sideband modulation techniques. Besides discussing the network...
A 40 Gb/s wavelength and return-to-zero (RZ) to non-RZ (NRZ) pulse format converter is experimentally demonstrated. The converter is based on wavelength conversion in a semiconductor optical amplifier (SOA) and detuned optical filtering. The ideal filter response is investigated, and approximated experimentally cascading two filters, for a 3 ps 40 Gb/s input RZ signal. An undistorted NRZ signal with...
The aim behind this work is to demonstrate that we can enhance the performances of a WDM system, with a symmetrical dispersion compensation scheme, by optimizing the channels power distribution. We will compare the performances in a 16 channels WDM system with a bit rate of 10 Gb/s/channel, in the case where the powers are uniformly distributed and when a binomial distribution is used. The idea behind...
The growing relevance of wireless communications has been driving the research and development of advanced network architectures to enable the cost-effective support of large numbers of users at very high data rates. In this context, the FUTON project aims to fulfil the objectives of the so-called 4th Generation (4G) through an innovative Distributed Antenna System (DAS) with centralized signal processing...
Fully-transparent DWDM networks working at 10 Gb/s or more have limited reach. At these high rates, only translucent networks able to fully regenerate the signal when needed can be used to implement long haul transport networks. Since signal regeneration and regenerator placement can be done in many ways, an effective design procedure will target the overall cost minimization. In this paper, we propose...
In Passive Optical Network (PON), which usually uses intensity modulated signals to convey information fiber nonlinearities are enhanced due to high input and pump powers, short channel spacing, high bit rates, high number of channels, etc. This paper proposes an optimization algorithm applied to PON based on wavelength division multiplexing (WDM) ring. The optimization consists in setting up initial...
In this paper, we study the performance of OFDM signals in frequency-interleaved WDM radio-over-fiber (RoF) links with optical channel selection made by a uniform Fiber Bragg grating (FBG). The frequency-interleaved signals, transported over 10 km of standard single mode fiber, were transmitted in optical double-sideband (ODSB) format and filtered in optical single-sideband (OSSB) format. The simulations...
This paper points out the benefit and scope of circuit switching in the future optical Internet. Given the increasingly excessive energy consumption by IP-based Internet routers which may lead to a constraint on Internet growth, the profile of Internet traffic and the high utilization achievable by dense wavelength division multiplexing, a conclusion can be made that efficient design of telecommunications...
In current optical switches, an entire wavelength is switched from a source node to a single destination node, thereby precluding fractional wavelength allocation. This limitation results in two major problems: (i) N(N-1) wavelengths are required to fully connect a network with N edge nodes; and (ii) traffic arriving at the core switch from multiple optical links cannot be groomed in the optical domain...
As an extension of the known light trail and light tree techniques, we explore the most possible general setting of time division multiplexing in circuit switched all optical networks. It will be shown that this technique improves the scalability and adaptability of all-optical networks without the need of expensive techniques like wavelength converters and burst switching or packet switching capable...
We have been witnessing a rapid transition to unified packet-based core/edge network architecture by major telecom carriers all around the globe. Core network architecture becomes a two-layer structure based on data packet transport over DWDM (Dense Wavelength Division Multiplex) bandwidth pipes, which is the most effective way of providing sharing network capacities, enabling efficient protection...
Wavelength division multiplexing systems use multiplexers and demultiplexers to increase network capacity by allowing several information channels to be placed into one fiber. Depending on the application multiplexers and demultiplexers can have wide, coarse or dense channel spacing as well as different number of channels that they process. There are many techniques available today for realization...
In this paper, a study on a fully passive WDM/PON ring architecture which reaches 19 km distance, while serving more than 1000 users with symmetric several hundred Mbit/s per user is presented. The design is based on SARDANA (Scalable Advanced Ring -based Passive Dense Access Network Architecture) and was generated as an alternative solution, with its novelty laying on the use of L-band in line remote...
The increasing demand for higher bit rates in access networks requires fibre deployment closer to the customer since bit rates in copper based access networks are strictly limited by the length of the copper cables. Besides higher access bit rates optical access network technologies enable extended distances between the network terminal at the customer premise and the line port at the access node...
We present experimental results on transmission of twenty 10 GE channels over 334 km long fibre link composed of 3 spans mixing 234 km of non-zero dispersion shifted (NZ DSF) and 100 km of standard single mode fibre (SSMF). Distributed Raman amplification in the 3 fibre spans is realized by counter-directional time division multiplexed pumping.
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