PROCESS FOR MAINTAINING IN SERVICE COAXIAL MULTICHANNEL INSTALLATIONS BY A TRANSMISSION NETWORK WHICH IS REMOTELY SUPPLIED AND COMPRISED OF SYMMETRIC CABLES, AND TRANSMISSION CHAIN FOR IMPLEMENTING SUCH PROCESS

摘要

Process for maintaining in service coaxial multichannel installations by a transmission network which is remotely supplied and comprised of symmetric cables wherein an amplification station is arranged for each line section. In each pth line section, wherein p is an integer selected as a function of the length and the characteristics of the line transmission and preferably equal to 4, 5 or 6, the peak network section embracing also the p line sections is corrected by means of a compensation effected by constant wiring compensation, the signal amplification in each line section being controlled by pilot signals of which the frequency is appropriately higher than that of the signal frequency range. The invention further relates to a multichannel transmission chain for data transmission with coaxial telecommunication installations and with a remotely supplied transmission network, conformed with symmetrical cables into at least one section, comprised of P line sections wherein P is appropriately equal to 4, 5 or 6 of the peak network and comprising an amplification station per line section. The stations comprise chain connected units such as the wiring compensation element, the adjusting circuit and the line amplifier, and a pilot signal receiver connected to the chain, whereas in the amplification station of each pth line section there is also inserted in the chain a peak network compensation element. The essential feature of the invention is that the coaxial installations are connected at the input, respectively at the output of the transmission network by means of transformers and that a precompensation is carried out on the 1st.../p-1/th line sections pertaining to the peak network section, wherein the attenuation for the pilot frequency corresponds to the correction attenuation value obtained in the pth line section, whereas in the signal transmission range it is lower than the correction attenuation. The essence of the invention lies further in the fact that the input and the output stages of coaxial installations are transformers (21) between the input transformer (21) and a wiring compensation element (22), being inserted in the chain an accessory compensation element (27) which, in the 1st.../p-1/th line sections is comprised of a precompensation element (371) with fixed attenuation and, in the pth line section, is comprised of a peak network compensation element (372) having individually adjustable characteristics.