Analysis of transmission parameters of metallic cables based on external conditions

Today, the metallic cables in access networks in cities are usually installed underground at shallow depths, nevertheless aerial installations are still very common especially in suburban and rural areas. Moreover, power-line communication systems over outdoor aerial high-voltage transmission lines are often used for broadband transmission as well. Since the transmission parameters of metallic lines are influenced by external environmental conditions, such as the temperature, humidity, etc., the resulting transmission performance of digital systems using these cables are influenced as well. Today, the large buildings, data centers and houses are usually covered by structured metallic cables and installations in order to connect network nodes, computers, etc. Thanks to that the frequency characteristics of attenuation monitored at these cables might potentially serve for the localization of inhomogeneity caused by fire or any external heat. This effect of external conditions is mostly noticeable at higher frequencies that is why it is necessary to perform accurate measurements using calibrated equipment and defined conditions. In this paper, we focused on performing necessary measurements of transmission characteristics of metallic cables containing symmetrical pairs under defined temperatures and their locations inside the oven to analyze the influence of space and heat conditions.