Vliv přenosových parametrů sestavené komunikace digitální účastnické smyčky na kvalitu služby

Abstract

The aim of this paper is to explore and during practical measurements in the laboratory to verify the dependence of interference on the quality of services. The work is focused on the study of the length dependence of transmission media, the influence of crosstalk and noise on VDSL technology. The theoretical part describes the various xDSL technology standards and factors that influence the quality of services on digital subscriber loop. Another part of the theoretical section is focused solely on the description of VDSL technology. For solving this issue a procedure is used, in which the binary file of the predefined sizes are transmitted at different distances, and at various transmission speed. Another monitored parameter is the influence of crosstalk, which is determined in the same manner as the previous effect, but there is monitored simultaneous transfer of multiple channels at once. The last parameter monitored is the dependence of transfer speed on the size of additive white noise. The result is a detailed analysis and description of the dependence of the transmission medium, the influence of crosstalk and white additive noise dependence on the quality of services. Individual findings are based on a graphic and verbal description of the situation. In the same way, the influence of crosstalk is described in the conclusion. The results of the findings are based on more than two thousand observed figures recorded during measurements. Based on the data of these measurements, the reader will find considerable influence the length of the transmission medium has both on the quality of services and the transmission speed.