2 Digital subscriber line VDSL2
2.12 Masks of the power spectral density used in 997 plans

So far we have met with predefined profiles VDSL2 connections have calendar as the frequency plans. Frequency plans determine which frequencies can be used for downstream or upstream. The maximum power level of the transmitted signal is nevertheless necessary determine to complete the definition of transmission parameters. Definition of performance level is going through a mask of the PSD (Power Spectral Density). The mask represents the peak power of the transmitted signal at a particular frequency.

PSD masks correspond with a specific frequency plan. The basic parameters are listed in the table below. Beyond the level of the transmitted signal, the individual masks also differentiate, for example, the use or non-use upstream bandwidth US0. The figure shows the progress masks 997E17-M2x-A. Parameters of the other masks for Europe are set out in the relevant Annex in the recommendation ITU-T G.993.2.

The basic parameters of the PSD mask for frequency plans 997.
Shortcut | Label | Utilization of band US0 | Upper limit frequency for upstream or downstream [kHz]
B7-1 | 997-M1c-A-7 | A | 7050
B7-3 | 997-M1x-M | M | 12000
B7-7 | HPE17-M1-NUS0 | N/A | 17664
B7-8 | HPE30-M1-MUS0 | N/A | 30000
B7-9 | 997E17-M2x-A | A | 17664
B7-10 | 997E30-M2x-MUS0 | N/A | 30000

The following conditions are valid for the upstream band US0 for each of masks:

A - corresponds to Annex A of ITU-T G.992.5,

M - corresponds to Annex M in the ITU-T G.993.2 or ITU-T G.992.5,

N/A - band US0 is not used for data transmission.

PSD mask 997E17-M2x-A with marked directions of transmission.