Duplexing methods for PON systems using multimode fiber with multicarrier transmission

Deploying a PON using multimode fiber in the access network is viewed as a costeffective solution. However, a multimode fiber link exhibits a time-dispersive nature. To cope with this problem, an OFDM transmission method is used. In this work, a comparison study on several duplexing methods for this system was performed to decide upon the recommended method for the system. The choices that were examined are: TDD, FDD, WDD and SDD (time-, frequency-, wavelength- and space- division duplexing). Based on the following criteria: channel characterization, flexible bandwidth proportion, crosstalk & beat noise impairment, components-saving and system capacity, it was concluded that SDD is the most feasible one among other choices, immediately followed by WDD

Novel optically transparent add/drop for use in high-speed packet-switched networks

We present a novel optically transparent add/drop node, which is able to drop data and simultaneously uses this encoded data for its add function. Hence, it does not need a local transmitter, it can process most modulation formats and can insert data at an equal or higher bit rate than the data that is dropped

Scalability of a packet-switched WDM MAN with support for optical multicasting

This paper addresses the scalability (in terms of the number of nodes) of a packetswitched WDM all-optical bi-directional ring for metropolitan area networks. The nodes enable adding/dropping packets to/from all WDM channels on the ring. The nodes are optically transparent to data packets that bypass them. At a linespeed of 2.5 Gbps using directly modulated DFB lasers separated by 400 GHz, EDFAs to compensate for optical power loss and Phasars for wavelength multiplexing/demultiplexing it has been experimentally observed that a single ring can support upto 8 transparent nodes

A Metropolitan Optical Network with Support for Multicasting in the Optical Domain

We present the FLAMINGO1 network architecture, an all-optical wavelength-and-timeslotted Metropolitan Optical Network based on a multiple-ring topology. A couple of important aspects of this architecture include all-optical packet switching at intermediate nodes on a ring and the ability to put IP packets directly over WDM channels. The rings of the network are interconnected with intelligent bridges, architecture of which is presented. The network also enables all-optical multicasting at intermediate nodes, the architecture of which is also presented. Power budget calculations have also been dealt with and discussed in detail

Scalability of an All-optical Multiwavelength Slottedring Metropolitan Area Network

In this paper simulation results of the bit error rate (BER) performance of an all-optical multiwavelength slotted-ring metropolitan area network (MAN) are presented. The simulation results provide insight into the signal-to-noise ratio (SNR) degradation as the optical ring is scaled up in terms of the number of access points on it. The results also enable us to understand the effect of inband crosstalk (generated by the adding and dropping of packets at the optically transparent access points) on the bit error rate. A few techniques to improve the BER performance, resulting from inband crosstalk, are proposed

Bitloading with reduced computational complexity order for a multicarrier multimode PON

Nowadays, multicarrier transmission technique, e.g., optical OFDM, receives quite intense attention in the optical communications and networking field due to its potential to provide dispersion compensation. Adaptive modulation level is commonly and naturally employed in relation to multicarrier transmission, provided (sub)channel state information is available. The modulation level adaptation is usually done by a bitloading mechanism. In our work, given some modulation formats that are to be used, we attempt to reduce the computational complexity order of the bitloading algorithm from the one that has been presented in the literature. The bitloading algorithm is applied to a multicarrier multimode PON