C-Nav 2050, Руководство пользователя

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2050 User Guide
Reliability
The entire system meets or exceeds a target availability of 99.9%. To achieve this, every
part of the infrastructure has a built-in back-up system.
All the reference stations are built with duplicate receivers, processors and communication
interfaces, which switch automatically or in response to a remote control signal from the
Network Processing Hubs / Centers. The data links from the
reference stations use the
Internet as the primary data link and are backed up by dedicated communications lines, but
in fact the network is sufficiently dense that the
reference stations effectively act as back up
for each other. If one or several fail, the net effect on the correction accuracy is not
impaired.
There are two continuously running Network Processing Hubs / Centers, each receiving all
of the reference site inputs and each with redundant communications links to the uplink
Land Earth Stations ( LES ). The Land Earth Stations are equipped with two complete and
continuously operating sets of uplink equipment arbitrated by an automatic fail over switch.
Finally, a comprehensive team of support engineers maintains round the clock monitoring
and control of the system.
The network is a fully automated self-monitoring system. To ensure overall system integrity,
an independent integrity monitor receiver, similar to a standard C-Nav or
StarFire

user
receiver, is installed at every reference station to monitor service quality. Data from these
integrity monitors is sent to the two independent processing hubs in Torrance, California
and Moline, Illinois. Through these integrity monitors the network is continuously checked
for overall
DGPS positioning accuracy, L-Band signal strength, data integrity and other
essential operational parameters.
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