262
14 Pseudo-Ranging Radio Navigation Systems
The BEIDOU network of no-request measuring stations is also located in China.
The long-term development strategy of the system assumes the creation of a global
network of stations to improve the accuracy of the navigation services of the BEIDOU
system.
There are two more regional SRNS:
• Japanese quasi-zenith satellite system (QZSS), designed to serve users in the
Pacific-Asian region.
• Indian satellite system (IRNSS), designed for autonomous navigation and time
support on the Indian Peninsula. The new name of the system is NavIC. The
NavIC system provides services with open and authorized access.
14.4 Functional Supplement to Global Satellite Radio
Navigation Systems
Airborne augmentation system (ABAS). The airborne augmentation system
(ABAS) ensures that the navigation services of the global navigation satellite
system (GNSS) comply with aviation requirements through special techniques for
processing GNSS data by onboard aircraft systems or integrating GNSS data with
data from other navigation systems.
ABAS is based on one of the following technologies:
• Receiver autonomous integrity monitoring (RAIM), which uses redundant GNSS
information to ensure the integrity of GNSS data;
• Autonomous onboard integrity monitoring (AAIM), which uses information from
additional onboard sensors to ensure the integrity of GNSS data;
• Integration of GNSS equipment with other sensors (e.g., inertial dead reckoning)
to provide improved performance of the onboard navigation system.
Satellite-based augmentation system (SBAS). Satellite-based augmentation
system (SBAS) is one of the most promising and complex augmentation systems.
These systems can be used not only in civil aviation, but also for other transport
systems, increasing their efficiency and safety.
The SBAS satellite augmentation system monitors the signals of the main satellite
constellation (GPS or GLONASS) using a network of observation stations distributed
over a wide geographic area. For each monitored satellite of the main satellite
constellation, SBAS estimates the errors of the transmitted ephemeris and satellite clock parameters and then transmits these corrections and other data to users via
the geostationary satellite (Fig. 14.10).
Most sources of GPS positioning errors are due to atmospheric (ionospheric
and tropospheric) interference and satellite timing delays. Positioning errors can
be measured by interrogated ground control points with high accuracy and then
transmitting this information to the user at the same frequency as the conventional
GPS signal.
14 Pseudo-Ranging Radio Navigation Systems
The BEIDOU network of no-request measuring stations is also located in China.
The long-term development strategy of the system assumes the creation of a global
network of stations to improve the accuracy of the navigation services of the BEIDOU
system.
There are two more regional SRNS:
• Japanese quasi-zenith satellite system (QZSS), designed to serve users in the
Pacific-Asian region.
• Indian satellite system (IRNSS), designed for autonomous navigation and time
support on the Indian Peninsula. The new name of the system is NavIC. The
NavIC system provides services with open and authorized access.
14.4 Functional Supplement to Global Satellite Radio
Navigation Systems
Airborne augmentation system (ABAS). The airborne augmentation system
(ABAS) ensures that the navigation services of the global navigation satellite
system (GNSS) comply with aviation requirements through special techniques for
processing GNSS data by onboard aircraft systems or integrating GNSS data with
data from other navigation systems.
ABAS is based on one of the following technologies:
• Receiver autonomous integrity monitoring (RAIM), which uses redundant GNSS
information to ensure the integrity of GNSS data;
• Autonomous onboard integrity monitoring (AAIM), which uses information from
additional onboard sensors to ensure the integrity of GNSS data;
• Integration of GNSS equipment with other sensors (e.g., inertial dead reckoning)
to provide improved performance of the onboard navigation system.
Satellite-based augmentation system (SBAS). Satellite-based augmentation
system (SBAS) is one of the most promising and complex augmentation systems.
These systems can be used not only in civil aviation, but also for other transport
systems, increasing their efficiency and safety.
The SBAS satellite augmentation system monitors the signals of the main satellite
constellation (GPS or GLONASS) using a network of observation stations distributed
over a wide geographic area. For each monitored satellite of the main satellite
constellation, SBAS estimates the errors of the transmitted ephemeris and satellite clock parameters and then transmits these corrections and other data to users via
the geostationary satellite (Fig. 14.10).
Most sources of GPS positioning errors are due to atmospheric (ionospheric
and tropospheric) interference and satellite timing delays. Positioning errors can
be measured by interrogated ground control points with high accuracy and then
transmitting this information to the user at the same frequency as the conventional
GPS signal.