GPS Flashcards
The navigation message contains clock correction parameters which are used for:
a) correction of satellite time
b) correction of receiver time
a) correction of satellite time
Pseudo random Noise: Code used for the ____ of the satellites and the measurement of the time taken by the signal to reach the receiver.
identification
GLONASS: _ satellites, _ orbital planes, orbital height of 19,100 km.
24, 3
In what type of nominal orbit are NAVSTAR satellites placed?
a) Nearly circular
b) Elliptical
a) Nearly circular
A GPS control segment consists of: Master ___ station, monitor stations and ground ___.
Control, antennas
Galileo: 1/2/3 clocks have been developed, a R___ Frequency Standard Clock and a Passive Hydrogen Maser clock.
2, Rubidium
In a GPS, primary position information is in the form of spheres with the airplane/satellites in the centre of the spheres.
satelllites
GPS er með 1575 MHz og 1227 MHz. Hvaða tíðni notar commercial flight og hvað mörg code?
1275 MHz og one code.
How does a receiver of the NAVSTAR GPS satellite navigation system determine the elevation and azimuth data of a satellite relative to the location of the antenna?
a) data is stored in the receiver together with the Pseudo Random Noise (PRN) code.
b) It calculates it by using almanac data transmitted by the satellites.
b) It calculates it by using almanac data transmitted by the satellites.
GPS time can be converted to UTC by application of the:
a) UTC parameters sent in the navigation message
b) Correction given by atomic clocks
a) UTC parameters sent in the navigation message
Hvað er RAIM?
Technique by which a receiver checks the reliability of the signals it is receiving and can detect if one of the signals is incorrect.
NAVSTAR: Receiver clock error is
a) corrected by using signals from four satellites.
b) negligibly small because of accuracy of the atomic clocks in the satellites
a) corrected by using signals from four satellites.
In a GNSS/GPS, a position line is obtained by:
a) timing the period that is taken for a satellites transmission to reach the aircrafts receiver
b) the aircrafts receiver measuring the time difference between signals received from a minimum number of satellites.
a) timing the period that is taken for a satellites transmission to reach the aircrafts receiver
Which of the following NAVSTAR GPS satellite navigation system codes can be processed by unauthorised civil aviation receivers?
a) C/A
b) C/A and P
a) C/A
How many clocks in a NAVSTAR satellite?
4
GPS satellites transmit on two L-band frequencies with different types of signals. Which of these are generally available for use by civil aviation?
a) L1-precise (P)
b) L1-corase acquisition (C/A) with selected availability (S/A)
b) L1-corase acquisition (C/A) with selected availability (S/A)
EGNOS (European Geostationary Navigation Overlay System) is a form of
a) Wide area differential GPS (WADGPS)
b) Local Area Differential GPS (LADGPS)
a) Wide area differential GPS (WADGPS)
In EGNOS and WAAS systems the corrections for an aeroplane’s GNSS receiver are broadcast:
a) By the wide area master station
b) via a geostationary satellite.
b) via a geostationary satellite.
Which one of the following systems is self contained? a) GPS b) Inertial Navigation System c) VOR/DME d) Basic RNAV system
b) Inertial Navigation System
Aircraft equipped to operate to RNP 1 and better, should be able to
a) compute the exact value of its position error
b) compute an estimate of its position error
b) compute an estimate of its position error
Where is RNP used?
a) For RNAV routes
b) For precision approaches
a) For RNAV routes
On some charts you will find “RNP AR APCH”. The AR means
a) Arriving
b) Authorization required
b) Authorization required
3D RNAV fixing provides
a) Horizontal and vertical profile guidance
b) Horizontal, vertical profile and time guidance
a) Horizontal and vertical profile guidance
A phantom station (as used in a 2D RNAV system) is
a) a waypoint defined by a radial and a DME distance from a VOR/DME station
b) A non existing VOR/DME station defined by two DME
a) a waypoint defined by a radial and a DME distance from a VOR/DME station
Which of the following lists all the parameters that can be determined by a GPS receiver tracking signals from 4 different satellites?
c. Latitude, longitude, altitude and time
d. Latitude, longitude and altitude
c. Latitude, longitude, altitude and time
WGS84 model of the earth is an
a. elipse b. geoid c. sphere
b. geoid
Which of the following lists all the parameters that can be determined by a GPS receiver tracking signals from 4 different satellites?
c. Latitude, longitude, altitude and time
d. Latitude, longitude and altitude
c. Latitude, longitude, altitude and time
In order to carry out an Independent three-dimensional fix. Receiver Autonomous Integrity Monitoring (RAIM) and failure detection and exclusion of any faulty satellite, signal reception is required from a minimum number of how many satellites?
a. 5
b. 6
b. 6
The distance between a NAVSTAR/GPS satellite and receiver is:
c. determined by the time taken for the signal to arrive from the satellite multiplied by the speed of light
d. determined by the phase shift of the Pseudo Random Noise code multiplied by the speed of light
c. determined by the time taken for the signal to arrive from the satellite multiplied by the speed of light
What type of satellite navigation system NAVSTAR/GPS receiver is most suitable for use on board an aircraft?
a. Multiplex
c. Multichannel
c. Multichannel
In the NAVSTAR/GPS satellite navigation system, receiver clock error:
a. is corrected by using signals from four satellites
b. can be minimised by synchronisation of the receiver clock with the satellite clocks
a. is corrected by using signals from four satellites
In relation to the NAVSTAR/GPS satellite navigation system, what is involved in the differential technique (D-GPS)?
a. The difference between signals transmitted on the L1 and L2 frequencies are processed by the receiver to determine an error correction
d. Fixed ground stations compute position errors and transmit correction data to a suitable receiver on the aircraft
d. Fixed ground stations compute position errors and transmit correction data to a suitable receiver on the aircraft
How does a receiver of the NAVSTAR/GPS satellite navigation system determine the elevation and azimuth data of a satellite relative to the location of the antenna?
b. The data is determined by the satellite and transmitted together with the navigation message
c. It calculates it by using Almanac data transmitted by the satellites
c. It calculates it by using Almanac data transmitted by the satellites
The different segments of the satellite navigation system NAVSTAR/GPS are the:
a. control, space and user
b. main control station, the monitoring station and the ground antennas
a. control, space and user
The main task of the user segment (receiver) of the satellite navigation system NAVSTAR/GPS is to calculate receiver position by:
a. selecting appropriate satellites automatically, to track the signals and to measure the time taken by signals from the satellites to reach the receiver
b. monitoring the status of the satellites, determine their positions and to measure the time
a. selecting appropriate satellites automatically, to track the signals and to measure the time taken by signals from the satellites to reach the receiver
The geometric shape of the reference system for the satellite navigation system NAVSTAR/GPS. defined as WGS 84. is:
a. a geoid
c. an ellipsoid
c. an ellipsoid
In relation to the satellite navigation system NAVSTAR/GPS. the term ‘inclination’ denotes the angle between the:
b. orbital plane and the equatorial plane
c. orbital plane and the earth’s axis
b. orbital plane and the equatorial plane
At what approximate height above the WGS-84 ellipsoid are NAVSTAR/GPS satellites circling the earth?
a. 20200 km
d. 19500 km
a. 20200 km
Which of the following data, in addition to the Pseudo Random Noise (PRN) code, forms part of the so called ‘Navigation Message’ transmitted by NAVSTAR/GPS satellites?
a. almanac data: satellite status information
b. data to correct receiver clock error; almanac data
a. almanac data: satellite status information
Phase modulation:
a. results in a change of polarisation of the modulated signal.
b. is a modulation form used in GPS where the phase of the carrier wave is reversed.
b. is a modulation form used in GPS where the phase of the carrier wave is reversed.
The VDB (VHF data broadcast) broadcasts the GBAS signal within its coverage area to avionics in GBAs-equipped aircraft. The VDB signal provided are:
a. error correction data, integrity data and approach data for more than one runway.
b. error correction data and integrity data.
a. error correction data, integrity data and approach data for more than one runway.
SBAS systems improve the performance of GPS by:
c. providing an additional signal to GPS receivers.
d. providing an additional signal coming from the geostationary satellites.
d. providing an additional signal coming from the geostationary satellites.
How many clocks are installed in each NAVSTAR GPS satellite?
b. 4
c. 2
d. 3
b. 4
GPS satellites transmit on two L-band frequencies with different types of signals. Which of these are generally available for use by civil aviation?
b. L1-coarse acquisition
c. L2-coarse acquisition (C/A)
b. L1-coarse acquisition
In accordance with ICAO Annex 10 the NAVSTAR/GPS global average 95% position accuracy in SPS should be :
a. 5m vertically
b. 13m horizontally
c. 30m horizontally
b. 13m horizontally
For what reason is a mask angle set-up in a GPS-receiver?
b. To deny the receiver the use of GPS-satellites with an elevation less than the mask angle.
c. To select from all visible GPS-satellites the satellite-configuration which results in the smallest GDOP.
b. To deny the receiver the use of GPS-satellites with an elevation less than the mask angle.
EGNOS (European Geostationary Navigation Overlay System) is a form of:
c. stand-alone Global Navigation Satellite System (GNSS)
d. Wide Area Differential GPS (WADGPS)
d. Wide Area Differential GPS (WADGPS)
In NAVSTAR/GPS the PRN codes are used to determine satellite __ and ___.
range, identification
The NAVSTAR/GPS constellation comprises __ satellites in __ orbits
24, 6
The NAVSTAR/GPS space segment:
a. provides X, Y, Z & T co-ordinates and the constellation data
b. provides X, Y & Z co-ordinates and monitoring of the accuracy of the satellite data
a. provides X, Y, Z & T co-ordinates and the constellation data
NAVSTAR GPS receiver clock error is removed by:
a. regular auto-synchronisation with the satellite clocks
b. synchronisation with the satellite clocks on initialisation
c. adjusting the pseudo-ranges to determine the error
c. adjusting the pseudo-ranges to determine the error
The contents of the navigation and systems message from NAVSTAR/GPS SVs include:
a. satellite clock error, almanac data, ionospheric propagation information
b. satellite clock error, almanac data, satellite position error
a. satellite clock error, almanac data, ionospheric propagation information
The orbital height of geostationary satellites is:
a. 35800 km
b. 10313 nm
c. 19330 km
a. 35800 km
Þetta er verulega tæpt, það er alltaf talað um 20,200 í GPS satellites.. er þetta eitthvað annað?
The azimuth and elevation of the satellites is:
c. determined by the receiver from the satellite almanac data
d. determined by the satellite and transmitted to the receiver
c. determined by the receiver from the satellite almanac data
The number of satellites required to produce a 4D fix is:
a. 3
b. 5
c. 4
d. 6
c. 4
How many satellites are needed for a 2D fix?
a. 4
b. 3
c. 5
d. 2
b. 3
‘Unauthorised’ civilian users of NAVSTAR/GPS can access:
a. the C/A code
c. the P code
d. the C/A and P codes
a. the C/A code
RAIM is achieved:
b. by ground monitoring stations determining the satellite range errors which are relayed to receivers via geo-stationary satellites
d. within the receiver
d. within the receiver
The NAVSTAR/GPS constellation comprises:
a. SVs each in 4 orbits
c. SVs each in 6 orbits
c. SVs each in 6 orbits
When flying under IFR using GPS and a multi-sensor system:
a. The GPS must be operating and its information displayed
d. The multi-sensor system must be operating and its information displayed
d. The multi-sensor system must be operating and its information displayed
In NAVSTAR/GPS the space segment:
b. Provides the positional information to the receiver
d. relays positional data from the control segment
b. Provides the positional information to the receiver
The major limitation in the use of GPS for precision approaches using wide area augmentation systems (WAAS) is:
a. degradation of range measurement because of ionospheric propagation errors
b. global coverage of WAAS is not available
c. the height difference between the ellipsoid and the earth
c. the height difference between the ellipsoid and the earth
EGNOS provides a WAAS by determining the errors in …… and broadcasting these errors to receivers using ……
a. SV range, pseudolites
b. X, Y & Z co-ordinates, geostationary satellites
c. X, Y & Z co-ordinates, pseudolites
d. SV range, geostationary satellites
d. SV range, geostationary satellites
The principle error in GNSS is:
a. receiver clock error
c. ionospheric propagation
c. ionospheric propagation
The NAVSTAR/GPS frequency available to non-authorised users is:
a. 1215.0 MHz
b. 1575.42 MHz
d. 1227.6 MHz
b. 1575.42 MHz
