Ublox RCB-F9T, Руководство по интеграции

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RCB-F9T - Integration manual
interface description [ 2 ]). The message UBX-NAV-SBAS provides detailed information about which
corrections are available and applied.
The most important SBAS feature for accuracy improvement is ionosphere correction. The
measured data from regional Ranging and Integrity Monitoring Stations (RIMS) are combined to
make a Total Electron Content (TEC) map. This map is transferred to the receiver via SBAS satellites
to allow a correction of the ionosphere error on each received signal.
Message type Message content Source
0(0/2) Test mode All
1 PRN mask assignment Primary
2, 3, 4, 5 Fast corrections Primary
6 Integrity Primary
7 Fast correction degradation Primary
9 Satellite navigation (ephemeris) All
10 Degradation Primary
12 Time offset Primary
17 Satellite almanac All
18 Ionosphere grid point assignment Primary
24 Mixed fast / long-term corrections Primary
25 Long-term corrections Primary
26 Ionosphere delays Primary
Table 12: Supported SBAS messages
Each satellite services a specific region and its correction signal is only useful within that region.
Planning is crucial to determine the best possible configuration, especially in areas where signals
from different SBAS systems can be received:
•
Example 1 - SBAS receiver in North America:
In the eastern parts of North America, make sure
that EGNOS satellites do not take preference over WAAS satellites. The satellite signals from
the EGNOS system should be disallowed by using the PRN mask.
• Example 2 - SBAS receiver in Europe: Some WAAS satellite signals can be received in the
western parts of Europe, therefore it is recommended that the satellites from all but the
EGNOS system should be disallowed using the PRN mask.
Although u-blox receivers try to select the best available SBAS correction data, it is
recommended to configure them to exclude unwanted SBAS satellites.
To configure the SBAS functionalities use the CFG-SBAS-* configuration group.
Parameter Description
CFG-SIGNAL-SBAS_ENA Enabled/disabled status of the SBAS subsystem
CFG-SBAS-USE_TESTMODE Allow/disallow SBAS usage from satellites in test mode
CFG-SBAS-USE_RANGING Use the SBAS satellites for navigation (ranging)
CFG-SBAS-USE_DIFFCORR Combined enable/disable switch for fast-, long-term and ionosphere corrections
CFG-SBAS-USE_INTEGRITY Apply integrity information data
CFG-SBAS-PRNSCANMASK Allows selectively enabling/disabling SBAS satellites
Table 13: SBAS configuration parameters
When SBAS integrity data are applied, the navigation engine stops using all signals for
which no integrity data are available (including all non-GPS signals). It is not recommended
UBX-22004121 - R01 3 Receiver functionality Page 20 of 64
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