GNSS Flashcards
What does GNSS stand for
GLOBAL NAVIGATION SATELLITE SYSTEM
What frequency band and range do GNSS satellites transmit in
UHF
300MHz - 3000MHz
How many satellites are required to obtain a position fix
4
What are the 3 major GNSS systems
1. USA
2. Russia
3. Europe
- NAVSTAR
- GLONASS
- GALILEO
What is the range in meters for GNSS accuracy error with 4 satellites
10 - 30m
What are the known 5 errors possible with GNSS systems
1. ____ delays
2. Satellite ____ errors
3. ____ uncertainty
4. ____ errors
5. ____ noise
- Atmospheric
- clock
- Orbit
- Multi-path
- Receiver
What does SBAS stand for
SATELLITE BASED AUGMENTATION SYSTEM
Allows for error correction
Uses a ground station to transmit errors to a geostationary satelite
Geostationary satelite transmits the error connections to the GNSS system
What does WAAS stand for
WIDE AREA AUGMENTATION SYSTEM
What does EGNOS stand for
EURO GEOSTRATIONARY NAVIGATION OVERLAY SERVICE
If using a SBAS system for error checking, what is the accuracy range in meters, laterally and vertically
1m Lateral
1.5m Vertical
What does DOP stand for
DILUTION OF PRECISION
Positon accuracy depends on the satellite positions in relation to receiver
What are the 3 planes of DOP (Dilution Of Precision)
P V H
PDOP - Position
VDOP - Vertical
HDOP - Horizontal
What does RAIM stand for
RECEIVER AUTONOMOUS INTEGRITY MONITORING
Ensures the receiver is able to see the correct number of satellites
What is the purpose of Receiver Autonomous Integrity Monitoring (RAIM)
Ensures receiver can see correct number of satellites
The concept of RAIM
How many satellite signals must be seen for RAIM to perform fault detection
5
