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The current generation of light wave systems benefit from increased transmission distance by using optical amplification and increased capacity by using dense wavelength division multiplexing (DWDM) technology. The reach of present systems is limited by the noise contributed by the used amplifiers, combined with nonlinear effects from transmission. This paper aims to address these issues.

The nature and extent of degradations in the optical DWDM systems due to these limiting factors have been discussed in this paper.

It has been learnt that stimulated Raman scattering (SRS), four wave mixing (FWM) and amplified spontaneous emission (ASE) are the important factors in optical DWDM systems. These factors limit the system capacity of the transmission systems drastically.

It can be concluded from the discussion that while designing an efficient DWDM system, an optimization of the channel separation and the amplifier separation is required to minimize the nonlinear effects (FWM and SRS) along with the ASE noise introduced by inline optical amplifications.

Fiber nonlinearities are anticipated to impose transmission limitations due to the enhanced total interaction length in long‐haul dense wavelength division multiplexing (DWDM) optical transmission systems. The purpose of this paper is to analytically study the combined effect of stimulated Raman scattering (SRS) and four‐wave mixing (FWM) in the presence of amplified spontaneous emission (ASE) noise generated by erbium‐doped fiber amplifiers (EDFAs).

The paper presents analytical analysis of DWDM optical transmission systems in the presence of two significant fiber nonlinearities (SRS and FWM).

Simple expressions are derived to study the dependence of signal‐to‐noise ratio (SNR) on the amplifier spacing between two consecutive amplifiers.

The authors have analytically studied the combined effect of SRS and FWM in the presence of ASE noise generated by EDFAs. The novelty of the work is that it has considered all the three factors simultaneously and the expressions are derived for calculation of SNR.

Fast iterative algorithms for designing birefringent filters with any specified spectral response are proposed. From the Jones formalism, we derive two polynomials representing the transmitted and rejected response of the filter, respectively. Once the coefficients of the filters are obtained, the orientation angle of each birefringent section and the phase shift introduced by each compensator can be determined by an iterative algorithm that gives an efficient solution to the birefringent filter design problem. Afterward, some design examples are presented to demonstrate the effectiveness of the proposed approach. In comparison with results reported in the literature, this approach provides the best performance in terms of accuracy and time complexity.

Based on work by Technology Task Group 1 (TTE‐1) for the IEEE‐USA/Cornell workshop on US telecommunications’ evolution. States the task group’s activity focused on local access Contains discussions on how fibre optics are used today and can be used in the future. Touches also on the technical and non‐technical challenges that a fibre to the home or fibre to the building network may face.

The writer of a review article in the IT area depends on a variety of information sources containing authoritative material, hyped‐up reports, or even partial or pure fiction. Sometimes articles are biased or the author has a particular axe to grind — for instance the person is associated with a company and the article is no more than a dressed up sales piece. Academics are usually reliable — although unlikely to damn themselves with faint praise if the next grant is round the corner. I will try to exercise good judgement when assessing my information sources, supressing my various prejudices if possible. But what is meant by the word new? For the purposes of this article ATM (Asynchronous Transfer Mode) protocol (rules) and ATM switches in broadband networks, and aspects of Cable‐TV and cable modems have received a lot of exposure. They will not be discussed here. However, there is much interest in the contest between fibreoptic systems to the home and the conversion of telephone lines to wideband lines. These topics will be discussed.

This paper aims to study the competition problems and market failures in the Canary Islands and propose an alternative management model for the telecommunication transmission network. This model is based on a wholesale-only open-access transmission network, available to all the retail service providers of this region, and managed by a unique entity subject to regulation with cost-based prices. The proposal hopefully will help to debate about the implementation of certain regulatory models in the network industries, concerning telecommunication submarine cables connecting archipelagos.

An empirical approach has been used, based on the observation and analysis of the regulatory policies applied to the wholesale transmission networks in the Canary Islands, Azores and Madeira archipelagos.

Results show a persistent margin squeeze situation on the retail broadband market in the Canary Islands, due to the pricing strategy on the Spanish mainland-Canaries wholesale market, which is, in turn, delaying the entry of alternatives and the level of development and efficiency of competition. The risk of duopoly collusion is also present on this wholesale market. Additionally, public aids will be needed to replace the systems connecting with the non-capital islands and to provide redundancy to El Hierro. The alternative proposal might help preventing the above. Eventually, several insights are considered for further investigation.

Little attention has been paid to this topic in the literature, regarding the analysis of regulatory policies applied over fiber optic submarine cable infrastructures in fragmented territories like archipelagos. Consequently, an empirical analysis has been accomplished to emphasize this research work, based on the regulatory policies adopted.