Planet Networking & Communication VC-200M, Руководство пользователя

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The screen contains the following details:
Setting Description
Direction Select the target direction of downstream or upstream.
Target SNRM Set the required SNR Margin×10(50=5dB), by default is
6dB .
z
Click “ CANCEL ” to exit from this page without saving the changes.
z
Click “ APPLY ” at any time during configure to save the information that you
have been entered.
4.1.3 Profile Configuration
VDSL2 was developed and standardized in record time to address the shortcomings of
existing access technologies. It servers as the ideal xDSL technology for eliminating
last-mile bottlenecks and enable global mass deployment of advance Triple Play
services.
Unlike its predecessor, which allowed choosing either DMT (Discrete Multitone) or
QAM (Quadrature Amplitude Modulation) technology, VDSL2 only uses the DMT
line code.
DMT is a method of separating a DSL signal so that the usable frequency range is
separated into multiple small frequency bands, or tone. It uses up to 4096 tones which
are spaced 4 kHz or 8 kHz apart. Each tone can be used for either downstream or
upstream.
However VC-200M/VC-200S provide 10 VDSL2 profiles: 8a, 8b, 12a, 12b, and 17a
frequency bands.
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