General concept of development of Russian regional telecommunication networks is considered. Conception is formed under taking into account world tendencies of telecommunications development based on optical networks.

Present article is devoted to study of a connection opportunity of erbium-doped fiber (amplifier EDFA), to the fiber-optic communication line (FOCL) by means of a unique fiber. As a result of it powerful pump radiation and information radiation are transferred in common on singlemode fiber. Such way of connection EDFA to FOCL is of interest at operation of a transfer line on explosive objects and etc., where entering electrical and electronic components into the certain zone is not supposed. The numerical ratings of nonlinear effects influence on an information signal are carried out for a case: an information at DWDM-signal in a range 1530 ... 1560 nm, pump on a wavelength 980 nm. As a making fiber was considered standard single mode fiber with a step structure of a refraction parameter change such as SF. Among nonlinear effects the following are considered: nonlinear attenuation and refraction, modulation instability, compelled_scatterion on acoustic waves and parametrical processes. Is shown, that the basic limiting factor on a pump is the self-focusing capacity, limiting at the end length of a supplying fiber in limits up to two kilometers. On such length the influence of nonlinear effects appears insignificant, that does not worsen appreciable quality of transfer.

The chain of kinetic equations for three-level macroscopic systems intersecting with an electromagnetic field on the basis of then method of elimination of the boson variables is obtained. On its basis the role of two-photon transitions is investigated.

Method of solution for electromagnet field computation in frequency domain for irregular dielectric waveguides with composite structure is represented. An algorithm for realization of mentioned method is proposed. Justification of method is represented.

Some quantum optical models possessing a transition from regular to chaotic dynamics and influence of 'quantum chaos' to photons statistics are investigated. Particular cases of semiclassical dynamics of a single atom and cooperative system of these atoms with (2j + 1) -- equidistant levels interacting with a quantized photon mode in an ideal cavity were considered. We take into account parametric pumping. Corresponding equations of motion are received without the rotation-wave approximation. It was demonstrated the scenario of transition to chaos, realized by doubling frequencies mechanism with growing of 'atom + field' coupling constant. Chaotic behavior and squeezing degree time dependence were obtained in computer simulations for coupling constant values of order of the atomic frequency, the calculation of the maximal Lyapunov coefficient for the dynamics of many two- level atoms interacting with photon cavity mode as function of 'atoms + field' interaction constant is performed. An influence of possible parametric instabilities of nonlinear media and effects of dissipation for atoms are discussed.

Nonlinear media properties influence greatly the trends of waves passage through various structures with the film of nonlinear materials. This paper considers the scope for the analytical inquiry into the passage of wave pulses through films of various nonlinear media in waveguide structures. The method under consideration can be taken into account when analyzing the passage of the pulses through the films with nonlinearly of different character, such as the films of paramagnetic, semiconductors including those with super lattice.

Approximation model, algorithm and results of statistical modeling of irregularity at fusion splice of conventional single-mode step index fibers are represented. Statistical characteristics have been obtained by the method of statistical modeling. At this step a probability distribution and its parameters were determined. An evaluation of probability of deviation from normative values based on investigation results was executed.

Existent methods of suppression of echo nuisance influence (methods of echo obstruction, echo compensation and self- balanced differential system) have their both advantages and disadvantages. For example widely used on USA and European networks echo compensator with higher subscriber transmission quality estimation then echo obstructer is not operable on significant part (20%) of Russian networks echo paths. Mentioned problem can be solved either by complication of echo suppressors technical realization under not guarantee of their 100% operability or by creation an echo suppressor of combined type. Combined echo suppressors must have positive properties of existent echo suppression methods. Methods of combined echo suppressor realization are considered. In addition an evaluation of their perspectives is done from the point of view of provided transmission quality.

The influence of multiray interference on a propagation pulsed signal in fiber-optic communication line (FOCL) is considered. The multiray interference appears for each place, where the defect on optical factor of refraction occurs. The problem of distortion pulsed signal becomes particularly actual with development high speed calculate optical networks, which have a high degree an structure, and appearance of transmit technology of information with a spectral compaction. This is explained increasing amount of components in a transmit tract. Such optical processes are like the processes, appearing in multiray Fabry-Perot interferometer (FPI). In approach to a propagation light wave is close to flat, the model of a segment FOCL is built on the base of an independent FPI elements composition. Such model has allowed to make the quantitative estimation of interference multiplicated hindrance parameters by means statistical description of many elements FPI in FOCL system. The studies have shown, that for reflect index from butt-end of fiber within 3...5% the typical peaks of intensity during increasing of a signal pulse front are appeared. This case the count threshold in a decisive device for pulse with garbled fronts is reached in other moment of time to not-garbled fronts. The time delay result in a phase delay between consequences of pulses, which increase the probability of reading errors the bits. For active components FOCL situation is danger, when all or part of interferometers leave maximum their own transmission and the reflected wave will appear. The estimation of its amplitude is carried out, the correlation function and the spectrum of many elements FPI in FOCL hindrances are putted.

We study the ability of optical fibers to resist the damaging effect of the electric discharge in relation with the power of optical emission transmitted via the fiber. A technique for testing optical fiber samples is discussed. The dependence of the damaging arc current on the power level of transmitted optical emission is considered. It is shown that the power of transmitted optical emission needs to be taken into account when estimating the resistance of the optical fiber to the effect of the electric discharge.

The fiber-optical cable installation on aerial high-voltage power lines is widely spread on the territory of Russia and has a huge perspective for development. Designing aerial fiber-optical communication lines there are some problems at choosing of suspension method and fiber-optical cable type. The calculation of aerial fiber-optical cable mechanical characteristics is most actual problem. The calculation should be made due to mechanical parameters of cable and electrical line towers. During service life aerial fiber-optic cable is subject to external influences under different environment conditions: temperature drops, wind pressure, ice loads. For constructing of reliable aerial fiber-optic communication line all those factors must be taken into account. For optical cable installation on towers should be calculated essential value of cable mounting sag and tension.

For fiber-optic links (FOL), the sufficient time of repairing (removing & reinstalling) fiber-optic cables (FOC) and the natural aging of optical fibers (OF) have been stipulating and propelling the problems of safe communication. The latters used to and are nowadays resolved by mean of either reserving line, cables, fibers, digital streams or improving quality of FOC grooming. In the latter case, the implementation of a prognostic control of FOC plays sufficient role in fault prediction on maintenance stage of FOL. The prognostic control is performed by mean of Remote Test Fiber Systems (RFTS) on the basis of both direct controlling OF parameters and indirect methods of FOC monitoring, including, being applied at Vol-gograd City Telephone Network, RLTP Method (Rate Loss Time Prediction) designed for copper/steel media. Thus for example a prediction method on the basis of protective sheath monitoring results of FOC. This method is very effective when applied for buried long-haul FOC and in widespread use in Russia. One of the problems of the method performance is how to maintenance satisfactory sheath condition of FOC. In general, the main trouble is how to localize faults on the protective sheath. There are however some classical techniques which are similar to the applied techniques in fault localization in copper media, but when applied for FOL, the techniques have specifics. The purpose of the paper is to analyze specifics of the classical technique implementation for fault localization of protective sheath of FOC.

The purpose of this article is to introduce the reader with the world of fiber optic media with its challenges and solutions, and also to present the Probable analysis method for conductive leak localization (PAMCLL) and to show how it works on fiber optic cable with armored sheath (FOCAS). One of the such challenges, considered in this article, for Russian fiber-optic links exploiting services is how to seek the 'ill- fated leak' (from the point of copper wire cylindroid, wrapped up with damaged polyethylene hose, into the ground) on buried long-haul FOCAS. It was PAMCLL that was selected to eliminate some typical problems occurring in process of localization. In abstract sense, PAMCLL is probable model describing the distribution of leak locations depending on the index of insulation of fantom pair, since the fault location is random variable.

A bursting character of telecommunication networks development has prompted the necessity to develop new technologies for installation of wire communication transmission lines. The main requirements associated with this technology are easy design, fast and economic installation, high capacity and security. In the light of these requirements this new technology for fiber-optic transmission line implementation presents interest for professionals in design, construction, installation and operation of primary telecommunication networks due to its feature concerned with suspension of optical cable over the towers of high-voltage aerial (electric) power lines (APL) instead of being buried into ground. The authors of this paper have given a scientific description of those main aspects of the new technology which were developed with their direct participation and the knowledge of which, will enable, as they believe, to provide a more extensive implementation of fiber-optic transmission lines utilizing APL.

Back scattering method is the most universal method applied to control fiber optic transmission line characteristics. This method is recommended by ICU-T and national standards of Russia. It is widely used during determination of regularity and attenuation of optical fibers, irregularity localization and its loss, evaluation of length of installed fiber optic lines, measurements of attenuation both individual sections and whole optical line, control of delivery length etc. Thus an error estimation of considered method during measurements of splice loss is necessary. Theoretical and experimental analysis of back scattering method error during splice loss measurements is represented.

Potential possibilities of Brillouin optical time domain reflectometers based on distributed fiber sensors measuring Landau-Placzec ratio are considered. Also perspectives of mentioned measurement device applications on optical networks are described.

During fiber optic communication lines restoration often appear optical cable short insert joint quality control needs. It is problem to measure of short cable insert fiber splice losses on long-haul optical communication lines. This problem is caused by limits of dynamic range and resolution of optical time domain reflectometer (OTDR). We present overview of ways of short cable insert optical power losses control on long- haul optical communication lines. Theoretical and experimental proof some of this methods is considered. Numerical results are represented. A good agreement of theoretically predicted and experimental values is demonstrated.

During realization of plan-prophylactic operations on fiber- optical transmission line (FOTL) at reflectometric measurements, with small duration of outgoing pulse, in a number of optical fiber fusion splicers the inhomogeneities as signals of return reflection were detected by one of the telecommunication operators in Volga region. In paper the results of a research the detected inhomogeneities with the help of full-scale measurements carried out during 1999 - 2000(Gamma) (Gamma) are given. The reasons, which could lead to appearance of return reflection signals on fusion splices, are analyzed, the recommendations on detection such fusion splices are made and the work package preventing appearance of fusion splices with reflections at a stage of FOTL building is offered.

Results of cycle temperature tests of optical fiber fusion splices are represented. An algorithm, method and object of investigation are described. Thermochamber providing temperature range from -- 60 degree(s)C to + 50 degree(s)C was used to carry out temperature tests. Whole delivery length of optical cable was tested. Fibers at the cable end were sequentially joined together. Two splice groups were investigated. First group consisted of splices with reflection attenuation less than 90 dB. Second group included splices with reflection attenuation more than 100 dB. One-half of each group splices was protected by sleeves, another -- by silicon gel. Splice parameters were measured by optical time domain reflectometer.

At present on the 'Rostelekom' communication network after three months service in various company branches, the trial operation of four monitoring systems have finished. Among them the special place is occupied by the Russian company 'Spectrum' remote fiber testing system (RFTS) 'Photon' having a number of essential differences from other analogues. During trial operation RFTS 'Foton' considerable material, which allows to evaluate quality of operation, was accumulated. For this purpose the results of automatic reflectograms comparison with standard (obtained on system installation step) are given in paper. Thus as a comparison test the value of attenuation deviation on supervising section by fiber length approximately 10 km was used. For finding the attenuation value on the analysis intervals (every reflectogram is divided into sections by length approximately 10 kms) the approximation by a method of two points is used. Results of measurements executed by Russian RFTS 'Photon' during 3 months experimental exploitation are represented.