Garmin G1000 Manual De Usuario

190-00498-07  Rev. A

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If a particular aspect of G1000 operational capability is not addressed by these commonly asked questions or in 

the index, contact Garmin (see the copyright page or back cover for contact information) or a Garmin-authorized 
dealer.  Garmin is dedicated to supporting its products and customers.

The Satellite Based Augmentation System (SBAS) uses a system of ground stations to correct any GPS signal 

errors.  These ground stations correct for errors caused by ionospheric disturbances, timing, and satellite 
orbit errors.  It also provides vital integrity information regarding the health of each GPS satellite.  The signal 
correction is then broadcast through geostationary satellites.  This correction information can then be received 
by any SBAS-enabled GPS receiver.

SBAS is designed to provide the additional accuracy, availability, and integrity necessary to enable users to rely 

on GPS for all phases of flight.

There are several SBAS systems serving different parts of the world.  The Wide Area Augmentation System 

(WAAS) is currently available in the United States, including Alaska and Hawaii.  The European Geostationary 
Navigation Overlay Service (EGNOS) offers coverage of Europe, parts of the middle east and northern Africa.  The 
Multi-functional Satellite Augmentation System (MSAS) covers mainly Japan and parts of northern Australia. 

Both LNAV/VNAV and LPV approaches use the accuracy of SBAS to include vertical (glide path) guidance 

capability.  The additional accuracy and vertical guidance capability allows improved instrument approaches to 
an expanded number of airports throughout the U.S.

The implementation of LPV approaches further improves precision approach capabilities.  LPV approaches 

are designed to make full use of the improved GPS signal from the SBAS. This approach combines the LNAV/
VNAV vertical accuracy with lateral guidance similar to the typical Instrument Landing System (ILS).  LPV 
approaches allow lower approach minimums.

In systems using the GIA 63, or when SBAS is unavailable, the GPS receivers use Receiver Autonomous 

Integrity Monitoring (RAIM) to perform the following functions:

• Monitor and verify integrity and geometry of tracked GPS satellites

•  Notify  pilot  when  satellite  conditions  do  not  provide  necessary  coverage  to  support  a  certain  phase  of

flight

• Predict satellite coverage of a destination area to determine whether the number of available satellites is

sufficient to satisfy requirements (refer to the System Overview Section for instructions on RAIM prediction)

• Detect and exclude bad satellites from the navigation solution (Fault Detection and Exclusion, FDE)

RAIM ensures that satellite geometry allows for a navigation solution calculation within a specified protection 

limit (4.0 nm for oceanic, 2.0 nm for enroute, 1.0 nm for terminal, and 0.3 nm for non-precision approaches). 
Without SBAS or RAIM, GPS position accuracy integrity cannot be monitored.