GNSS adminSeptember 21, 2023October 14, 2023CHAPTERWISE QUESTIONS OXFORD, RADIO NAVIGATION Results - GNSS GNSS HD Quiz powered by harmonic design #1. NAVSTAR/GPS operates in the band the receiver determines position by: UHF, range position lines UHF, range position lines UHF, secondary radar principles UHF, secondary radar principles SHF, secondary radar principles SHF, secondary radar principles SHF, range position lines SHF, range position lines #2. The NAVSTAR/ GPS control segment comprises: the space segment, the user segment and the ground segment the space segment, the user segment and the ground segment a ground segment and the INMARSAT geostationary satellites a ground segment and the INMARSAT geostationary satellites a master control station, a back-up control station and five monitoring stations a master control station, a back-up control station and five monitoring stations a master control station, a back-up control station, five monitoring stations and the INMARSAT geostationary satellites a master control station, a back-up control station, five monitoring stations and the INMARSAT geostationary satellites #3. The orbital height and inclination of the NAVSTAR/GPS constellation are: 20180 km, 65° 20180 km, 65° 20180 km, 55° 20180 km, 55° 19099 km, 65° 19099 km, 65° 19099 km, 55° 19099 km, 55° #4. The model of the earth used for NAVSTAR/GPS is: WGS90 WGS90 PZ90 PZ90 WGS84 WGS84 PZ84 PZ84 #5. The minimum number of satellites required for a 3D fix is: 3 3 4 4 5 5 6 6 #6. The NAVSTAR/GPS operational constellation comprises how many satellites 12 12 21 21 24 24 30 30 #7. The most accurate fixing information will be obtained from: four satellites spaced 90° apart at 30° above the visual horizon four satellites spaced 90° apart at 30° above the visual horizon one satellite close to the horizon and 3 equally at 60° above the horizon one satellite close to the horizon and 3 equally at 60° above the horizon one satellite directly overhead and 3 equally spaced at 60° above the horizon one satellite directly overhead and 3 equally spaced at 60° above the horizon one satellite directly overhead and 3 spaced 120° apart close to the horizon one satellite directly overhead and 3 spaced 120° apart close to the horizon #8. The most significant error of GNSS is: GDOP GDOP Receiver clock Receiver clock Ionospheric propagation Ionospheric propagation Ephemeris Ephemeris #9. The frequency available to non-authorised users of NAVSTAR/GPS is: 1227.6 MHz 1227.6 MHz 1575.42 MHz 1575.42 MHz 1602 MHz 1602 MHz 1246 MHz 1246 MHz #10. The purpose of the pseudo-random noise codes in NAVSTAR/GPS is to: identify the satellites identify the satellites pass the almanac data pass the almanac data pass the navigation and system data pass the navigation and system data pass the ephemeris and time information pass the ephemeris and time information #11. The minimum number of satellites required for receiver autonomous integrity monitoring is 3 3 4 4 5 5 6 6 #12. If a receiver has to download the almanac, the time to do this will be: 2.5 minutes 2.5 minutes 12.5 minutes 12.5 minutes 25 minutes 25 minutes 15 minutes 15 minutes #13. The use of LAAS and WAAS remove the errors caused by: propagation, selective availability, satellite ephemeris and clock propagation, selective availability, satellite ephemeris and clock elective availability, satellite ephemeris and clock elective availability, satellite ephemeris and clock GDOP, selective availability and propagation GDOP, selective availability and propagation receiver clock, GDOP, satellite ephemeris and clock receiver clock, GDOP, satellite ephemeris and clock #14. The most accurate satellite fixing information will be obtained from NAVSTAR/GPS & GLONASS NAVSTAR/GPS & GLONASS TRANSIT & NAVSTAR/GPS TRANSIT & NAVSTAR/GPS COSPAS/SARSAT & GLONASS COSPAS/SARSAT & GLONASS NAVSTAR/GPS & COSPAS/SARSAT NAVSTAR/GPS & COSPAS/SARSAT #15. A LAAS requires: an accurately surveyed site on the aerodrome and a link through the INMARSAT geostationary satellites to pass corrections to X, Y & Z co-ordinates to aircraft an accurately surveyed site on the aerodrome and a link through the INMARSAT geostationary satellites to pass corrections to X, Y & Z co-ordinates to aircraft an accurately surveyed site on the aerodrome and a link through the INMARSAT geostationary satellites to pass satellite range corrections to aircraft an accurately surveyed site on the aerodrome and a link through the INMARSAT geostationary satellites to pass satellite range corrections to aircraft an accurately surveyed site on the aerodrome and a system known as a pseudolite to pass satellite range corrections to aircraft an accurately surveyed site on the aerodrome and a system known as a pseudolite to pass satellite range corrections to aircraft an accurately surveyed site on the aerodrome and system known as a pseudolite to pass corrections to X, Y & Z co-ordinates to aircraft an accurately surveyed site on the aerodrome and system known as a pseudolite to pass corrections to X, Y & Z co-ordinates to aircraft #16. The position derived from NAVSTAR/GPS satellites may be subject to the following errors: selective availability, skywave interference, GDOP selective availability, skywave interference, GDOP propagation, selective availability, ephemeris propagation, selective availability, ephemeris GDOP, static interference, instrument GDOP, static interference, instrument ephemeris, GDOP, siting ephemeris, GDOP, siting #17. EGNOS is: the proposed European satellite navigation system the proposed European satellite navigation system a LAAS a LAAS a WAAS a WAAS a system to remove errors caused by the difference between the model of the earth and the actual shape of the earth a system to remove errors caused by the difference between the model of the earth and the actual shape of the earth #18. The PRN codes are used to: determine the time interval between the satellite transmission and receipt of the signal at the receiver determine the time interval between the satellite transmission and receipt of the signal at the receiver pass ephemeris and clock data to the receivers pass ephemeris and clock data to the receivers synchronise the receiver clocks with the satellites clocks synchronise the receiver clocks with the satellites clocks determine the range of the satellites from the receiver determine the range of the satellites from the receiver #19. The availability of two frequencies in GNSS: removes SV ephemeris and clock errors removes SV ephemeris and clock errors reduces propagation errors reduces propagation errors reduces errors caused by GDOP reduces errors caused by GDOP removes receiver clock errors removes receiver clock errors #20. The NAVSTAR/GPS reference system is: A geo-centred 3D Cartesian co-ordinate system fixed with reference to the sun A geo-centred 3D Cartesian co-ordinate system fixed with reference to the sun A geo-centred 3D Cartesian co-ordinate system fixed with reference to the prime meridian, equator and pole A geo-centred 3D Cartesian co-ordinate system fixed with reference to the prime meridian, equator and pole A geo-centred 3D Cartesian co-ordinate system fixed with reference to space A geo-centred 3D Cartesian co-ordinate system fixed with reference to space A geo-centred 3D system based on latitude, longitude and altitude A geo-centred 3D system based on latitude, longitude and altitude #21. The initial range calculation at the receiver is known as a pseudo-range, because it is not yet corrected for: receiver clock errors receiver clock errors receiver and satellite clock errors receiver and satellite clock errors receiver and satellite clock errors and propagation errors receiver and satellite clock errors and propagation errors receiver and satellite clock errors and ephemeris errors receiver and satellite clock errors and ephemeris errors #22. The navigation and system data message is transmitted through the: 50 Hz modulation 50 Hz modulation The C/A and P PRN codes The C/A and P PRN codes The C/A code The C/A code The P code The P code #23. An all in view receiver: informs the operator that all the satellites required for fixing and RAIM are in available informs the operator that all the satellites required for fixing and RAIM are in available checks all the satellites in view and selects the 4 with the best geometry for fixing checks all the satellites in view and selects the 4 with the best geometry for fixing requires 5 satellites to produce a 4D fix requires 5 satellites to produce a 4D fix uses all the satellites in view for fixing uses all the satellites in view for fixing #24. When using GNSS to carry out a non-precision approach the MDA will be determined using: barometric altitude barometric altitude GPS altitude GPS altitude Radio altimeter height Radio altimeter height Either barometric or radio altimeter altitude Either barometric or radio altimeter altitude #25. If an aircraft manoeuvre puts a satellite being used for fixing into the wing shadow then: the accuracy will be unaffected the accuracy will be unaffected the accuracy will be temporarily downgraded the accuracy will be temporarily downgraded the accuracy will be temporarily downgraded the accuracy will be temporarily downgraded the receiver will maintain lock using signals reflected from other parts of the aircraft with a small degrading of positional accuracy the receiver will maintain lock using signals reflected from other parts of the aircraft with a small degrading of positional accuracy #26. Which of the following statements concerning NAVSTAR/GPS time is correct? satellite time is the same as UTC satellite time is the same as UTC the satellite runs its own time based on seconds and weeks which is independent of UTC the satellite runs its own time based on seconds and weeks which is independent of UTC the satellite runs its own time based on seconds and weeks which is independent of UTC the satellite runs its own time based on seconds and weeks which is independent of UTC the satellite runs its own time based on seconds and weeks which is correlated with UTC the satellite runs its own time based on seconds and weeks which is correlated with UTC satellite time is based on sidereal time satellite time is based on sidereal time Finish GNSS