these bits are either re-allocated to another tone or removed completely.
Bits
Tab: Displays the bits allocated per tone. The results can be displayed in graphical format or tabular formats or modes.
In ADSL, Discrete Multi-Tone (DMT), divides the signal into multiple carriers (bins) centered in multiples of 4.3125 kHz. The
spectrum of each bin overlaps with its neighbors i.e. it is not confined to a 4.3125 kHz wide channel because the orthogonality of
COFDM makes this possible without interference. Up to 15 bits per symbol can be encoded on each bin on a good quality line.
BX100A Bits/Tone (graph mode)
BX100V Bits/Tone (graph mode
)
Each tone (bin) represents a 4.3125 kHz bandwidth and is used to transfer up to 15 bits in a single direction. In VDSL2 Bandplan
30a, the tone bandwidth is increased to 8.625kHz.
Note: Bits/Tone
The Bits/Tone graph is a useful visual tool to quickly identify interference or cross talk issues
The graphical mode can provide valuable insight to ADSL spectrums or VDSL2 channel plan implemented.
The table below represents the Tone Allocations in ADSL/2+
* ADSL2+ only
** Not all tones are used
Note:
Applies to non-overlapped PSD masks only
BX100A/V e-Manual D07-00-001 Rev E01
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