Investigation on the electric field strength radiated from G.fast data carrying copper telecommunication network

摘要

G.fast technology provides low cost ultra-fast broadband by transmitting high frequency signals through existing copper telecommunication network. Unfortunately, copper telecommunication network is not originally designed for data transmission on high frequencies, resulting with cable radiation when G.fast signal is transmitted. This radiation can interfere with radio services operating in the same frequency range and cause serious disturbances of the radio signal reception, thus disabling radio services to operate as intended. In order to limit radiation from telecommunication network various limits have been proposed. This paper gives the comparison between defined radiation limits and measurements of the E-field radiation from the unshielded copper telecommunication cable (TK 33-U) when G.fast (profile 106a) signal is transmitted. The results show that limit values proposed in ITU-T K.60 and FCC Volume 47 Part 15 recommendation overestimate while radiation limits proposed in ECC/REC/(05)04 recommendation underestimate radiation from TK 33-U cable. Additionally, measurement results show that E-field strength is below the ITU and FCC recommended limits, even when the unbalanced cable is used.