Modeling of Environmental Influences at the Signal Transmission by means of VDSL and PLC Technologies

For successful understanding of the signal transmission on metallic homogeneous symmetric lines, it is necessary exactly to recognize essential negative influences in the real environment of local subscriber loops. This contribution discusses frequency characteristics of linear negative influences on transmitted signal, near-end and far-end crosstalks and the impulse noise in the xDSL environment. For the expansion of communication systems on low-voltage power distribution cables, it is necessary to have a detailed knowledge of the PLC transmission environment and, therefore, this contribution discusses also negative influences in the real environment of customer cable installations. A main attention is focused on the description of the proposed VDSL and PLC simulation models and on the explanation of simulation methods for substantial negative influences. Presented information represents a reach enough knowledgebase for the extended techniques of the VDSL and PLC signal transmission that can be extremely helpful for various tests and performance comparisons.