Vyyo Inc. V290iA, Руководство пользователя

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2 Physical and Functional Description
12 V290iA User Guide
Power
The V290iA supports an input voltage of 48VDC (36-72 VDC), with 5A input current
protection. The V290iA has a manageable Power and Control Card, providing power to
the different units, such as the Cisco cards, the V284+A card, and the temperature
control system
Modem V290iA Initialization Process
Upon power up, the V290iA performs the following:
1. Scans for a UHF downstream channel – The modem always stores the last set of
parameters it was able to work with. It therefore first tries to reacquire the last
working downstream channel.
2. Synchronizes to the downstream channel – The downstream signal is valid when
the modem has the following:
„
QAM synchronization.
„
FEC synchronization.
„
MPEG frames synchronization.
„
Recognition of a MAC synchronization message.
3. Receives upstream parameters – The WMTS periodically transmits on the
downstream channel a broadcast information message to all modems on the sector
regarding upstream channels in the sector. The upstream information includes
symbol rate, modulation, FEC, preamble and scrambling.
4. Receives bandwidth allocation MAP – The WMTS periodically transmits on the
downstream channel a broadcast message to all modems on the sector regarding
the upstream bandwidth access opportunities of a coming time interval.
5. Performs ranging and adjustments – The modem synchronizes with the WMTS
on the upstream timing, frequency and transmission power.
6. Establishes IP connectivity – The modem acquires the network setting (IP
address, subnet mask and more) from the DHCP server. The modem entry in the
DHCP server is configured through the Vyyo Web NMS (refer to the
NMS User
Guide ).
7. Establishes Time of Day – The modem acquires the date and time from a time
server, for proper messaging.
8. Acquires configuration – The modem downloads its configuration file from a TFTP
server. The TFTP file name is provided by the DHCP server, and is configured
through the Vyyo Web NMS (refer to the
NMS User Guide ). The modem
configuration file includes information about downstream and upstream channels,
available services, service classifiers and priorities, etc.
9. Registers with the WMTS .