Anna V. Andrianova

UWB-RoF optical signal relevant to state committee on radio frequency spectral mask and its chirping task

The article covers issues on optical pulses modeling for UWB-RoF transmission system and State Committee on Radio Frequency (SCRF) spectral mask. It is assumed that the whole range is covered only by a modulator (information source). The problem concerns pulse transmission received over a fiber optic line of 100 km in length. It was found that the output optical signal obtains significant chirping, which has a negative impact on the Radio-over-Fiber (RoF) transmission system. In this paper, it is proposed to select the optical pulses at a predetermined optical line, or use a chirped small amplitude Gaussian pulse on the input. This can significantly increase, more than twofold, the length of the optical line.

Experimental study of wireless part of laboratory bench, implementing IR-UWB radio-over-fiber system

Wireless part of the laboratory bench, implementing IR-UWB Radio-over-Fiber system, is described in the paper. Experimental prototype of fractal antenna radiating system (FARS) is considered, various transmission modes of the laboratory bench, which allow to investigate technical specifications, are described. Research results are presented and analyzed.

Experimental demonstration of high-speed data transmission based on Gaussian pulses for IR-UWB radio-over-fiber systems

Experimental bench, which provides high-speed data transmission for IR-UWB Radio-over-Fiber systems on the basis of Gaussian pulses, is presented in the paper. Experiment setup and results are described and discussed.

The fiber optic device for signal positive chirping by interferential method with tuning of chirp size

The device for positive chirping of a signal in a fiber optical line is offered. The device is based on two Fabry–Perot resonator with additional fiber optical cannels. If to execute the amalgamator from an erbium doped material, the device will supply amplification of a target signal, which is important for distribution access systems (for example, Radio-over- Fiber systems (RoF)). The device provides selectivity for spectral components of entrance radiation, that allows to operate of chirp. Built-in the converter of length provides in additional fiber optical cannels tuning the chirp under the given size.

Corrective chirp adding for minimizing distortion in Radio-over-Fiber System fiber optic line

Corrective chirp for distortion minimization in fiber optic line in Radio-over-Fiber systems is considered in the paper. It is suggested to use Mach-Zehnder modulator for corrective chirp adding. Corrective chirp is added by tapering the bias point of Mach-Zehnder modulator. Corrective chirp mathematical model is considered in the paper. Also mathematical model of the signal with corrective chirp that transmitted in Radio-over-Fiber systems is considered in the paper. Simulation model of suggested construction scheme of fiber optic section is considered. Experimental results of Radioover-Fiber system with corrective chirp is presented in the paper.

Constructive functional principles and control objectives executed with the device for optical signal splitting and chirping

This paper describes functional principles of a device for optical signal splitting and chirping. The offered device is to fulfill functions of such optical signal distortions compensation within FOCL RoF as linear attenuation (LA) and chromatic dispersion (CD); and it should also split optical signals for its feeding to radio emitting components, compounding aerial array (AA), and control radio emitting antenna lobe. In the meantime the device for optical signal splitting and chirping can inject losses into transferred signal, though they should be within tolerant values for conventional FOCL components.

Optical signal splitting and chirping device modeling

This article examines the devices for optical signal splitting and chirping device modeling. Models with splitting and switching functions are taken into consideration. The described device for optical signal splitting and chirping represents interferential splitter with profiled mixer which provides allocation of correspondent spectral component from ultra wide band frequency diapason, and signal phase shift for aerial array (AA) directive diagram control. This paper proposes modeling for two types of devices for optical signal splitting and chirping: the interference-type optical signal splitting and chirping device and the long-distance-type optical signal splitting and chirping device.

Interference fiber optic device for RoF antenna radiators control

Calculation of profiled optical element is described in the paper. This element is a part of fiber optic device intended to be used in Radio-over-Fiber systems. Calculation is based on Manakov equation system for forward and backward inter-group interference rays. Numerical integration of second order wave equation is used only for 50 microns element length. For 200 microns element length this calculation is diverged. 3D profile for element refractive index is obtained from calculations.

Application of the device based on chirping of optical impulses for management of software-defined networks in dynamic mode

The analysis of the influence of the physical layer concepts in optical networks on the performance of the whole network. It is concluded that the relevance of the search for new means of transmitting information on a physical level. It is proposed to use an optical chirp overhead transmission between controllers SDN. This article is devoted to research of a creation opportunity of optical neural switchboards controlled in addition by submitted optical radiation. It is supposed, that the managing radiation changes a parameter of refraction of optical environment of the device, and with it and length of a wave of information radiation. For the control by last is used multibeam interferometer. The brief estimation of technical aspects of construction of the device is carried out. The principle of using the device to an extensive network. Simulation of network performance parameters.

Nanocrystalline glass-ceramics implementation methods and refractive index modelling thereof

Clear nanocrystalline material receipt possibilities are described in the paper. We investigated the possibility to process the glass-ceramics and quartz by intense torsion under high pressure. We found that due to the lack of plasticity of the material zone to maintain the integrity of the sample it is necessary to apply heating up to 200-250°C. The resulting material is supposed to be used in fiber-optic telecommunication systems. We conducted mathematical modeling of the refractive index in the linear and nonlinear mode capacities for nanostructured glass-ceramics. The analytical method is based on the strain oscillator motion under outer light wave effect model. We also found the coefficient of nonlinear stiffness for nanostructured glass-ceramics.