EFFICIENCY OF TELECOMMUNICATION SYSTEMS TRANSMISSION OF FIXED BROADBAND ACCESS THROUGH TELEPHONE CABLES

Abstract

The article provides an assessment of the efficiency of transmission data systems by digital subscriber lines of fixed broadband access over multi-pair telephone cables using the transient interference compensation system “vectoring” between transmission systems. A technique for calculating the signal-to-noise ratio at the receiver input is proposed, which takes into account frequency characteristics and additive interference of lines, uncompensated transient interference between mutually influencing transmission systems, and the limitation of the power of transmitted signals associated with the normalization of the transmitter power, caused by the use of the “vectoring” system. The effectiveness of transmission systems with the help of the transient interference compensation system “vectoring” is evaluated by broadband access network models using G.fast technology when using a multi-pair telephone cable of the TPP type with the number of pairs up to 100 in the frequency range up to 106 MHz and line lengths up to 250 meters. The achievable transmission speed is estimated depending on the characteristics of subscriber lines, the number of parallel operating transmission systems and the limitation of the transmitted signal power. It was determined that the main reason for limiting the achievable speed of information transmission when using the “vectoring” system is the frequency characteristics and additive interference of subscriber lines, uncompensated transient interference and limitation of the power of the transmitted signal. The proposed method of evaluating the signal/noise ratio and the achievable speed of data transmission with vectoring transient interference compensation systems can be applied in the tasks of designing and building fixed broadband access networks that use multi-pair telephone cables and twisted pair cables as a transmission medium.