|Fast access to subscriber terminals (FAST) – Power spectral density specification
|ITU TELECOMMUNICATION STANDARDIZATION SECTOR COORDINATES STANDARDS FOR TELECOMMUNICATIONS AND INFORMATION COMMUNICATION TECHNOLOGY (ITU-T)
Recommendation ITU-T G.9700 specifies power spectral density (PSD) mask requirements for fast access to subscriber terminals (G.fast), a set of tools to support reduction of the transmit PSD mask, profile control parameters that determine spectral content, including the allowable maximum aggregate transmit power into a specified termination impedance, and a methodology for transmit PSD verification. It complements the physical layer (PHY) specification in Recommendation ITU-T G.9701. Amendment 1 provided support for a new 106 MHz profile with +8 dBm maximum aggregate transmit power. Amendment 2 aligns the text of clause 6.5 on notching of specific frequency bands with ITU-T G.9701 (2014) and its latest amendments, completes the specification of 212 MHz profiles, adds Annex X ”Adaptation to the coax medium” in support of Annex X ”Operation without multi-line coordination intended for a crosstalk free environment” that has been specified in Amendment 3 to ITU-T G.9701, and updates the table of International amateur radio frequencies in Appendix I. The 2019 version of ITU-T G.9700 integrates the previous version and its amendments, and adds a new 106 MHz limit PSD mask intended to be used for transmission over networks with increased shielding, such as those with shielded cables or where cables are buried underground.