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White LED diodes are increasingly used. Thanks their features they are also used for illumination and gradually replace the classical light bulbs and fluorescent tubes. The one of advantages of white LED diodes is their availability for the Visible Light Communication. This article deals with study of suitable placing of light sources for indoor. The aim is a uniform light distribution and thereby...
In this article the composite author dealt with measurement possibilities of polarization states of light source emitting 1550 nm which was affected by atmospherically transmission environment in special acrylate box 2.5 m long. The Polarimeter Thorlabs TXP 5004 and the External Sensor Head PAN5710IR3 measured the changes of polarization parameters, ellipticity and azimuth, defining placement on the...
This article aims for meeting with influences of the atmosphere on real professional Free-Space Optical (FSO) link. Atmospheric effects could cause a degradation of quality of FSO communication and of received optical beam in shape of decreasing of optical power value through parameter RSSI (Received Signal Strength Indicator). Finally, this could even lead to communication loss. The article focuses...
Free Space Optics (FSO) is a data transmission technology using an optical beam going through the atmosphere. This communication technology has several indisputable advantages but also disadvantages. The one of the disadvantages are the thermal turbulences. This paper deals with the artificial thermal turbulences which affect the optical beam going from the commercial FSO head. The new against articles...
This article presents the concept of deploying Software Defined Radio (SDR) for laser beam modulation in Optical Wireless Communication (OWC). To achieve modulation and demodulation of the beam generated by Laser Diodes (LDs). SDR is used to provide a sophisticated and flexible possibility of readjustment without deeper intervention into the electronics of the OWC connection. To make conclusions regarding...
This article presents new insights in the research of VLC communication transmitter based on multimode optical fibres. Optical transmitters are formed by a different number of optical fibres. These fibres illuminate the defined surface area in the form of the 1/8 of the sphere, which simulates the room corner. The aim of this article is to point to possible new trends in the field of research such...
This article explores the influence of the concentrated carbon dioxide (CO2) gas on the different Phase Shift Keying (PSK) modulations used for Optical Wireless Communication (OWC) links. In this work, the OWC consisted of a laser diode, a photodetector, and a transmission medium. The Universal Software Radio Peripheral (USRP) unit created and evaluated the PSK modulations. This unit modulated the...
This article is dealing with fiber optics application into the geological monitoring. The distributed temperature systems (DTS) are optoelectronic devices, which can continuously measure the temperature and strain along optical cables. These systems use the advantageous properties of optical fibers, which can equally act as sensors. Currently, the DTS systems begin to be applied across the entire...
In this article the author team dealt with possibilities of using different types of modulation formats (NRZ, RZ (33%, 50%, CSRZ 67%, CRZ), DB, RZ-DPSK, NRZ-DPSK) for WDM-PON network with a view to point to merit of individual modulation types regarding to bit rate change and link distance. The individual modulation formats are then evaluated with perspective to limits of access networks based on...
This article deals with problem of thermal turbulence effects created by direct heaters on optical link which used OOK modulation for communication. For the purpose of uniform conditions of thermal turbulences with speed of 3.5 m·s1 and temperature 48 °C the special laboratory box was made. On the transmitting side the bit rate (0–160 Mbps) of optical link was changed and on the receiving side was...
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