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Many steganographic algorithms have been proposed until these days. They all try to hide information by relying on some of well-known techniques. However, each of these techniques has its advantages and also its drawbacks. In this paper, we have investigated a possibility of using tool known as Mojette Transform for modifying and scrambling a binary image containing secret information. The image after...
Free Space Optics wireless communication is a progressive communication technology. Despite the fact that it has been announced to the commercial market for a while, there are some fundamental problems to be considered. This paper deals with the negative weather influences which significantly deteriorate particular communication. FSO links themselves are not capable of link 99,999% availability per...
This article is devoted to the simulations and analysis of passive optical networks PON (Passive Optical Network) and FTTx (Fibre To The x) in the OptSim programme environment. The real network simulation is done as a prevention of complications in the final construction of optical network, which is designed for specific user requirements. TUKE (Technical University of Košice) has built a physical...
The Mojette (MOT) transform is a relatively new method for image transformation. With the use of MOT on images, multimedia files, distributed databases before information transmission became possible to reconstruct the data even if some part of information were damaged. The Mojette transform similarly to the Radon transformation calculate a group of projection on an image block. As result of this...
This article describes the vertical traffic signs recognition (VTSR) system. In this system the Cambridge optical correlator is used as an image comparator in the recognition stage. In our case, the Cambridge optical correlator compares detected traffic signs with reference traffic signs. One step of the VTSR system is the traffic signs detection process. Traffic signs detection is used to locate...
This article focuses on the creation of a four-channel WDM (Wavelength Division Multiplexing) system using SOA (Semiconductor Optical Amplifier) at the speed of 10 Gbps and the spacing of 1nm. In creating an optical network it is necessary to utilise software tools simulating a real optical network under the given conditions. Evaluation of the optical line quality for the respective channel is performed...
The Mojette transform has found several applications to this date. Some of them, such as systems for distributed file storage, or digital tomography systems exploit one of the main properties of Mojette transform - redundancy. However, sometimes this feature is not desirable. This is a case of applying Mojette transform for image encoding, or decoding. In these applications, higher rate of redundancy...
This work on the introduction deals with phenomena affecting the signal transmission in optical fibers. The core of the work is focused on nonlinear phenomenon SBS, one of the dominant nonlinear effects in optical communication systems. The main idea is impact of SBS at fully WDM optical communication systems. Therefore, it will also debated WDM technology, namely DWDM. The work will also be solution...
Free Space Optics commonly called FSO systems is a wireless technology which has been on a market for several decades. Despite its primary purpose — in army environment — this technology took its place in a commercial use. FSO communication has some unique advantages mainly because it still not as popular as traditional Ethernet or RF (Radio Frequency) wireless links. FSO is license free and relatively...
The aim of this paper is to design a system that will provide the necessary information about the quality of traffic signs. The inventory system includes various functional block that are described in detail. Based on database of traffic signs we will carry out audits of a particular traffic signs located at a certain position. The database will provide the data necessary for a comprehensive evaluation...
This article is devoted to influences in optical fibers. The main impact on quality of transmission signals have nonlinear phenomena. Their formation it isn't accidental. Very important position has transmission speed and cleanness of material. In this age exist many different approaches to produce optical fibers. Next pages describe an overview of nonlinear effects and simulations opto-electronics...
This paper deals with Free Space Optics (FSO) systems. Availability and reliability of FSO is taken under the scope. FSO links transmit data within the infrared wavelength region. Lasers are used to create medium to carry informational stream. FSO systems need Line of Sight (LOS) technology in order to maintain connection between two points. Weather conditions have quite significant impact on FSO...
This paper deals with fibreless optical link in combining with Radio Frequency (RF) link. Each of links has advantages which make them convenient for reliable high speed communication link The transmission medium is air for both links. Atmospheric phenomena cause decreasing of transmitted signal in different ways. The fog, dust and small particles are critical parameter for Free Space Optics (FSO)...
This paper focuses on the analysis of passive optical network (Passive Optical Network - PON) by the program package OptSim and the subsequent measurement of a simulated network using OTDR (Optical Time Domain Reflectometer) in a functional physical model of optical fibre networks created by KEMT FEI TUKE (Department of Electronics and Multimedia Communications, Faculty of Electrical Engineering and...
Control systems in general are very important in these days. There are used in many industrial fields such as automotive, medicine and manufacture. This paper contains a draft of VTSIS (Vertical Traffic Signs Inventory System). VTSIS has wide application in the control of traffic signs, which number is increasing annually. Cambridge optical correlator is used in designed inventory system as comparator...
The Mojette Transform is a mathematical transform that has approximately 20 years of research history. The transform is the exact definition of the Discrete Radon transform. Despite of the simplicity of its mathematics, this transform is a really computationally intensive procedure. The purpose of this paper is to introduce algorithms based on the Mojette Transform that the research group (composed...
Proposed paper contains an appropriate opportunities how to get information about availability of Free Space Optic (FSO) systems. The FSO systems use infrared beams to transmit data via atmosphere. Transmission channel is unstable and unpredictable, so monitoring of environment is needed. Atmosphere phenomena decrease optical signal in different ways such as absorption, scattering and scintillation...
Modern industrial quality monitoring systems are based on optical fibre sensors, microelectronic sensory technology and miniaturized infrared spectroscopy systems based on low-power, low-cost, high-efficient and innovative hardware solutions. The proposed paper presents development work related to create remote control system for monitoring water pollution petrochemical products using optical fibre...
Paper presents design, experiments and results with Optical Correlator based Traffic Signs Inventory System. The system has been designed and tested on highway D1 on Slovakia. The real traffic scenes were used. The system consists of five main blocks; Video Capture, GPS module, Preprocessing, Optical Correlation and Display. Video is captured with color camera and GPS coordinates are continuously...
The today computers, as taught in the elementary computer architecture courses, are based essentially on the principles, suggested by von Neumann in a 1946 report. Since that, only minor improvements have been carried out, although the impressive technical developments seem to hide this fact. In the meantime, also a whole software industry has grown up, and masses of society are using computers, sometimes...
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