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The different segments of the satellite navigation system navstar/gps are the ? [ Answer reports ]

Question 196-1 : Control space and user main control station the monitoring station and the ground antennas antenna the receiver and the central control unit cdu atomic clock power supply and transponder

Admin . main tasks of the control segment are . managing sps performance. navigation data upload. monitoring satellites.the space segment consists of a notional constellation of 24 operational satellites .the user segment is the gps receiver side exemple 296 Control, space and user.Control, space and user.

One of the tasks of the control segment of the satellite navigation system ?

Question 196-2 : Monitor the status of the satellites manufacture and launch the satellites manipulate the signals of selected satellites to reduce the precision of the position fix grant and monitor user authorisations

Admin . main tasks of the control segment are . managing sps performance. navigation data upload. monitoring satellites.the space segment consists of a notional constellation of 24 operational satellites .the user segment is the gps receiver side exemple 300 Monitor the status of the satellites.Monitor the status of the satellites.

The main task of the user segment receiver of the satellite navigation system ?

Question 196-3 : Selecting appropriate satellites automatically to track the signals and to measure the time taken by signals from the satellites to reach the receiver transmitting signals which from the time taken are used to determine the distance to the satellite monitoring the status of the satellites determine their positions and to measure the time monitoring the orbital planes of the satellites

Admin . user segment .gps supplies three dimensional position fixes and speed data plus a precise time reference the gps receiver used in aviation is a multi channel type and is able to determine the distance to a satellite by determining the difference between the time of transmission by satellite and the time of reception exemple 304 Selecting appropriate satellites automatically, to track the signals and to measure the time taken by signals from the satellites to reach the receiver.Selecting appropriate satellites automatically, to track the signals and to measure the time taken by signals from the satellites to reach the receiver.

One of the tasks of the space segment of the satellite navigation system ?

Question 196-4 : Transmit signals which can be used by suitable receivers to determine time position and velocity transmit signals to suitable receivers and to monitor the orbital planes autonomously compute the user position from the received user messages and to transmit the computed position back to the user segment monitor the satellites'orbits and status

Admin .the space segment consists of a notional constellation of 24 operational satellites .they are orbiting the earth in orbits inclined 55° to the plane of the equator in a nearly circular orbit of the earth at an altitude of 20 200 km 10 900 nm .each satellite broadcasts ranging signals on two uhf frequencies l1 and l2 providing for suitable receivers signals to determine time position and velocity exemple 308 Transmit signals which can be used, by suitable receivers, to determine time, position and velocity.Transmit signals which can be used, by suitable receivers, to determine time, position and velocity.

In civil aviation the height value computed by the receiver of the satellite ?

Question 196-5 : Height above the wgs 84 ellipsoid geometric height above ground height above mean sea level msl flight level

Admin .the geodetic reference datum used is wgs 84 .in the civil aviation field altitudes and flight levels are.defined in terms of atmospheric pressure points on the ground are defined by their planimetric coordinates and by their orthometric height or altitude which use as their reference the geoid corresponding to mean sea level .the heights derived from gnss systems use the wgs 84 ellipsoid as their reference and are thus different from the values of the orthometric height at the same point .the height difference between the ellipsoid gnss height reference and the geoid orthometric height reference is called the undulation of the geoid this value thus defines the distance of the geoid above positive undulation of the geoid or below negative undulation of the geoid the reference ellipsoid .this gives us the relationship .undulation of the geoid = ellipsoidal height orthometric height altitude .the aeronautical information service publishes the values of the undulation of the geoid for each ifr aerodrome .this value conventionally designated gund is expressed in feet it will be shown on the charts as and when they are amended exemple 312 Height above the wgs-84 ellipsoid.Height above the wgs-84 ellipsoid.

In relation to the satellite navigation system navstar/gps the term ?

Question 196-6 : Orbital plane and the equatorial plane horizontal plane at the location of the receiver and the direct line to a satellite orbital plane and the earth's axis horizontal plane at the location of the receiver and the orbital plane of a satellite

Admin . 2606.the orbital planes of the satellite navigation system navstar/gps are inclined 55° to the equatorial plane exemple 316 Orbital plane and the equatorial plane.Orbital plane and the equatorial plane.

How long does it take a navstar/gps satellite to orbit the earth ?

Question 196-7 : Approximately 12 hours one day 12 days 365 days because the satellites are located in a geostationary orbit

Admin . 2607.the 24 satellites that make up the gps space segment are orbiting the earth about 12 000 miles above us they are constantly moving making two complete orbits in less than 24 hours these satellites are travelling at speeds of roughly 7 000 miles an hour .the orbital period is exactly one half a sidereal day 11 hours and 58 minutes so that the satellites pass over the same locations or almost the same locations every day exemple 320 Approximately 12 hours.Approximately 12 hours.

At what approximate height above the wgs 84 ellipsoid are navstar/gps ?

Question 196-8 : 20200 km 10900 km 36000 km 19500 km

Admin .the satellites are in a nearly circular orbit of the earth at an altitude of 20 200 km 10 900 nm .the gps satellites are orbiting the earth in orbits inclined 55° to the plane of the equator .it consists of a notional constellation of 24 operational satellites the satellites are distributed in 6 orbital planes with at least 4 satellites in each .the orbital period is exactly one half a sidereal day 11 hours and 58 minutes so that the satellites pass over the same locations or almost the same locations every day exemple 324 20200 km.20200 km.

In which frequency bands are the l1 and l2 frequencies used by the satellite ?

Question 196-9 : Uhf vhf ehf shf

Admin .the navigation message contains . almanac data. ephemeris. satellite clock correction parameters. utc parameters. ionospheric model. satellite health data.each gps satellite transmits data on two uhf frequencies l1 1575 42 mhz and l2 1227 6 mhz .l1 is a standard accuracy signal designed for civil users world wide and l2 is a high accuracy signal modulated by a special code for authorised user only exemple 328 Uhf.Uhf.

In relation to the satellite navigation system navstar/gps which of the ?

Question 196-10 : Prn is a code used for the identification of the satellites and the measurement of the time taken by the signal to reach the receiver prn is the atmospheric jamming that affects the signals transmitted by the satellites prn describes the continuous electro magnetic background noise that exists in space prn occurs in the receiver it is caused by the signal from one satellite being received from different directions multipath effect

Admin .the c/a code is a pseudo random noise prn code sequence repeating every millisecond each c/a code is unique and provides the mechanism to identify each satellite .for information .gps receiver is able to determine the distance to a satellite by determining the difference between the time of transmission by satellite and the time of reception the initial distance calculated to the satellites is called pseudo range because the difference between the gps receiver and the satellite time references initially creates an erroneous range exemple 332 Prn is a code used for the identification of the satellites and the measurement of the time taken by the signal to reach the receiver.Prn is a code used for the identification of the satellites and the measurement of the time taken by the signal to reach the receiver.

Which of the following navstar/gps satellite navigation system codes can be ?

Question 196-11 : C/a ppp c/a and p p and y

Admin .this question also appears at the exam under the following statement .'unauthorised civilian users of navstar gps can access .the c/a code' .gps system satellites transmit their signals on two carrier wave l1 and l2 .l1 is a standard accuracy signal designed for civil users world wide and l2 is a high accuracy signal modulated by a special code for authorised user only .c/a code coarse acquisition clear access or civil access is modulated on the l1 carrier only the p code precise or protected is modulated on both carriers .l1 1575 42 mhz.l2 1227 6 mhz.l1 is the higher frequency .l1 is modulated with the p and c/a code exemple 336 C/a.C/a.

Almanac data stored in the receiver of the satellite navigation system ?

Question 196-12 : Fast identification of received signals coming from visible satellites recognition whether selective availability sa is operative assignment of received prn codes pseudo random noise to the appropriate satellite correction of receiver clock error

Admin .the gps almanac is a set of data that every gps satellite transmits and it includes information about the state health of the entire gps satellite constellation and coarse data on every satellite's orbit .when a gps receiver has current almanac data in memory it can acquire satellite signals and determine initial position more quickly exemple 340 Fast identification of received signals coming from visible satellites.Fast identification of received signals coming from visible satellites.

How does a navstar/gps satellite navigation system receiver recognise which of ?

Question 196-13 : Each satellite transmits its signal on common frequencies with an individual pseudo random noise code the doppler shift is unique to each satellite the receiver detects the direction from which the signals are received and compares this information with the calculated positions of the satellites each satellite transmits its signal on a separate frequency

exemple 344 Each satellite transmits its signal, on common frequencies, with an individual pseudo random noise code.Each satellite transmits its signal, on common frequencies, with an individual pseudo random noise code.

Which of the following data in addition to the pseudo random noise prn code ?

Question 196-14 : Almanac data satellite status information time positions of the satellites data to correct receiver clock error almanac data time data to impair the accuracy of the position fix

.the 'navigation message' provides all the necessary information to allow the user to perform . the positioning service ephemeris parameters needed to compute the satellite coordinates with enough accuracy the time parameters and clock corrections to compute satellite clock offsets and time conversions . the service parameters with satellite health information used to identify the navigation data set exemple 348 Almanac data; satellite status information.Almanac data; satellite status information.

What is the time taken to receive the complete navigation message complete set ?

Question 196-15 : 12 5 minutes = 30 seconds per data frame 12 hours = period of the satellites orbit 25 seconds = 1 second per data frame 24 seconds = 1 second per data frame

exemple 352 12.5 minutes (= 30 seconds per data frame).12.5 minutes (= 30 seconds per data frame).

Which of the following statements concerning the l1 and l2 navstar/gps ?

Question 196-16 : The higher frequency is used to transmit both the c/a and p codes c/a and p codes are transmitted at different times on both frequencies the higher frequency is only used to transmit the p code the lower frequency is used to transmit both the c/a and p codes

Admin .gps system satellites transmit their signals on two carrier wave l1 and l2 .l1 is a standard accuracy signal designed for civil users world wide and l2 is a high accuracy signal modulated by a special code for authorised user only .c/a code coarse acquisition clear access or civil access is modulated on the l1 carrier only the p code precise or protected is modulated on both carriers .l1 1575 42 mhz.l2 1227 6 mhz.l1 is the higher frequency .l1 is modulated with the p and c/a code exemple 356 The higher frequency is used to transmit both the c/a and p codes.The higher frequency is used to transmit both the c/a and p codes.

Which one of the following errors can be compensated for by a navstar/gps ?

Question 196-17 : Ionospheric delay multipath tropospheric receiver noise

Admin .this question also appears at exams with the following wording 'gps receivers using both gps frequencies l1 and l2 can nearly eliminate .ionospheric propagation delay' .ionospheric delay can be compensated by a navstar/gps . 2608.influenced propagation of radio waves through the earth's atmosphere .while radio signals travel with the velocity of light in the outer space their propagation in the ionosphere and troposphere is slower .in the ionosphere in a height of 80 400 km a large number of electrons and positive charged ions are formed by the ionizing force of the sun the electrons and ions are concentrated in four conductive layers in the ionosphere d e f1 and f2 layers these layers refract the electromagnetic waves from the satellites resulting in an elongated runtime of the signals .these errors are mostly corrected by the receiver by calculations the typical variations of the velocity while passing the ionosphere for low and high frequencies are well known for standard conditions theses variations are taken into account for all calculations of positions exemple 360 Ionospheric delay.Ionospheric delay.

Concerning the navstar/gps satellite navigation system what is the meaning of ?

Question 196-18 : It is a technique by which a receiver ensures the integrity of the navigation information it is the ability of the gps satellites to check the integrity of the data transmitted by the monitoring stations of the ground segment it is a method whereby a receiver ensures the integrity of the pseudo random noise prn code transmitted by the satellites it is a technique whereby the receivers of the world wide distributed monitor stations ground segment automatically determines the integrity of the navigation message

Admin .raim is a technique whereby a receiver processor determines the integrity of the navigation signals .raim is achieved by consistency check among pseudo range measurements .basic raim requires 5 satellites a 6th is for isolating a faulty satellite from the navigation solution .for information when a gps receiver uses barometric altitude as an augmentation to raim the number of satellites needed for the receiver to perform the raim function may be reduced by one exemple 364 It is a technique by which a receiver ensures the integrity of the navigation information.It is a technique by which a receiver ensures the integrity of the navigation information.

What is the inclination to the equatorial plane of the satellite's orbit in the ?

Question 196-19 : 55° 45° 35° 65°

Admin . 2606.the orbital planes of the satellite navigation system navstar/gps are inclined 55° to the equatorial plane exemple 368 55°.55°.

In respect of the use of gnss dilution of precision dop is a loss of accuracy ?

Question 196-20 : Relative position of the visible satellites ionospheric effects use of satellites at low altitudes multi path signals from some satellites

Admin .the position dilution of precision pdop is the geometric effect resulting from satellites being too close together satellites that appear farther apart in the sky provide a more accurate position solution than ones close together in the latter case the position accuracy is degraded in a similar fashion to when position lines from ground based navaids navigational aids are less than 45° since the ephemeris of each satellite is known by the gps global positioning system receiver it is possible to calculate which combination of gps satellites provides the best geometry at a given time this is translated into a figure called the position dilution of precision pdop since the satellites move across the sky relative to the user the pdop is always changing a low pdop is better a pdop of 4 to 6 is considered good position solutions calculated when the pdop is from 6 to 10 should be used cautiously because they may have significant error a pdop that is above 10 indicates unacceptable error . /com en/com062 646 jpg.the icao international civil aviation organization states that a pdop of less than 6 is required for en route navigation with a pdop of 3 or less required for nonprecision approaches i e not ils types exemple 372 Relative position of the visible satellites.Relative position of the visible satellites.

Which one of the following is an advantages of a multi sensor system using ?

Question 196-21 : The gnss can be used to update the fms position from a drifting irs the activation of 'selective availability' can be recognised by the ins the fms always uses average position calculated from the gnss and the irs the gnns is never used as an input in a multi sensor system

Admin .what is a multi sensor system in aviation it's a fmc flight management computer .informations received from a gnss are well more accurate than an ins while computing our position from different sources the fmc can use gnss position to continuously 'correct' the information received from the ins we will not correct physically the drift exemple 376 The gnss can be used to update the fms position from a drifting irs.The gnss can be used to update the fms position from a drifting irs.

What type of clock is used in navstar gps satellites ?

Question 196-22 : Atomic quartz mechanical laser

exemple 380 Atomic.Atomic.

How many clocks are installed in each navstar gps satellite ?

Question 196-23 : 4 3 2 1

exemple 384 4.4.

What is egnos european global navigation overlay system ?

Question 196-24 : Wide area differential gps wadgps local area differential gps ladgps glonass local area augmentation system laas

Admin . egnos european geostationary navigation overlay service consists of 3 geostationary inmarsat satellites which broadcast gps look alike signals .egnos is designed to improve accuracy to 1 2m horizontally and 3 5 m vertically.integrity and safety are improved by alerting users within 6 seconds if a gps malfunction occurs up to 3 hrs gps alone . wadgps is an acronym for wide area differential gps it's a general term for solutions used to enhance gps accuracy over large areas e g north america or europe .wadgps solutions usually use a network of ground based stations that compare their precisely known location with locations calculated from gps satellite signals any differences found can be used to create correction data that's broadcast from satellites ..satellite based augmentation systems include . egnos in western europe and the mediterranean. waas in usa. msas in japan. gagan in india exemple 388 Wide area differential gps (wadgps).Wide area differential gps (wadgps).

In accordance with icao annex 10 the navstar/gps global average 95% position ?

Question 196-25 : 13 m horizontally 30 m horizontally 22 m in 3d 5 m vertically

Admin .the us department of defense has released the new gps performance standard in october 2001 taking into account the new levels of performance achievable without sa selective availability according to the revised performance standard for gps sps standard positioning service positioning accuracy standards are given as dod 2001 .global average positioning domain accuracy .= or < 13 meters 95% all in view horizontal error signal in space only .= or < 22 meters 95% all in view vertical error signal in space only exemple 392 13 m horizontally.13 m horizontally.

In relation to the satellite navigation system navstar/gps 'all in view' is a ?

Question 196-26 : Is tracking more than the required 4 satellites and can instantly replace any lost signal with another already being monitored requires the signals of all visible satellites for navigation purposes is receiving and tracking the signals of all 24 operational satellites simultaneously is receiving the signals of all visible satellites but tracking only those of the 4 with the best geometric coverage

exemple 396 Is tracking more than the required 4 satellites and can instantly replace any lost signal with another already being monitored.Is tracking more than the required 4 satellites and can instantly replace any lost signal with another already being monitored.

The gps control segment consists of ?

Question 196-27 : A master control station monitor stations and ground antennas a master control stations and monitor stations a master control station monitor stations and geostationary satellites a master control station monitor stations ground antennas and geostationary satellites

Admin .the control segment permits to ensure that the transmitted data of the satellites is controlled and updated from time to time by ground stations . main tasks of the control segment are . managing sps performance. navigation data upload. monitoring satellites.the control segment comprises . a master control station. ground antenna. monitoring stations.for information .the space segment consists of a notional constellation of 24 operational satellites .the user segment is the gps receiver side exemple 400 A master control station, monitor stations and ground antennas.A master control station, monitor stations and ground antennas.

One of the tasks of the gps control segment is ?

Question 196-28 : To detect the malfunctioning of satellites to control continuously the motion of gps satellites to calculate and transmit differential corrections to users to calculate the accuracy of gps

exemple 404 To detect the malfunctioning of satellites.To detect the malfunctioning of satellites.

One of the tasks of the gps control segment is ?

Question 196-29 : To determine and send new ephemeris and new satellite clock error data to the gps satellites to control continuously the position and the motion of gps satellites to calculate and transmit differential corrections to users which are able to receive wide area differential gps systems to regulate the transmitted power by the satellites

The control segment comprises . a master control station. ground antenna. monitoring stations.the master control station is responsible for all aspects of the constellation command and control .the main tasks of the control segment are . managing sps performance. navigation data upload. monitoring satellites exemple 408 To determine and send new ephemeris and new satellite clock error data to the gps-satellites.To determine and send new ephemeris and new satellite clock error data to the gps-satellites.

For what reason is a mask angle set up in a gps receiver ?

Question 196-30 : To deny the receiver the use of gps satellites with an elevation less than the mask angle to make the receiver select gps satellites with a certain optimum elevation which is about equal to the mask angle to eliminate the reception of the signal from gps satellites with an elevation of about 90° to select from all visible gps satellites the satellite configuration which results in the smallest gdop

Admin .mask angle is that angle above the horizon below which satellites will not provide a usable signal to the receiver .the mask angle is generally set to 5 degrees as a default although the user is provided with the capability to select other mask angles exemple 412 To deny the receiver the use of gps-satellites with an elevation less than the mask angle.To deny the receiver the use of gps-satellites with an elevation less than the mask angle.

What is the function of the control segment in gps navstar ?

Question 196-31 : To ensure the transmitted data of the satellites is controlled and updated from time to time by ground stations it calculates the aircraft position to monitor and ensure that the transmitted signals are saved and processed to utilise waas to transmit a signal used by a suitable receiver to calculate position

Admin .the control segment consists of five monitor stations hawaii kwajalein ascension island diego garcia colorado springs three ground antennas ascension island diego garcia kwajalein and a master control station mcs located at schriever afb in colorado the monitor stations passively track all satellites in view accumulating ranging data this information is processed at the mcs to determine satellite orbits and to update each satellite's navigation message updated information is transmitted to each satellite via the ground antennas .these updates synchronize the atomic clocks on board the satellites to within a few nanoseconds of each other and adjust the ephemeris of each satellite's internal orbital model the updates are created by a kalman filter that uses inputs from the ground monitoring stations space weather information and various other inputs exemple 416 To ensure the transmitted data of the satellites is controlled and updated from time to time by ground stations.To ensure the transmitted data of the satellites is controlled and updated from time to time by ground stations.

The term 'sbas' signifies ?

Question 196-32 : Satellite based augmentation systems supplemental based augmentation systems service broadcast application systems satellite based area systems

Admin . the principle of a sbas to measure on the ground the signal errors transmitted by gnss satellites and transmit differential corrections and integrity messages for navigation satellites . 2609 exemple 420 Satellite based augmentation systems.Satellite based augmentation systems.

The term 'gbas' signifies ?

Question 196-33 : Ground based augmentation systems general broadcast application systems ground based augmentation software gps based augmentation standard

Admin .the gbas ground segment consists of three or four gbas reference receivers that are sited typically on or near an airport property these reference receivers track the signals from navigation satellites and pass pseudorange measurements and other information relevant to signal health and system performance monitoring to a central processing facility .the central processing facility uses the multiple redundant observations of the pseudoranges to compute estimates of the pseudorange corrections for each satellite signal observed by the reference receivers .the central processing facility also monitors the signal integrity and computes parameters for each satellite that the user may use to determine the availability of the signal in space for a desired level of service and a given satellite geometry . 2609.the differential corrections and integrity information are broadcast to the user exemple 424 Ground based augmentation systems.Ground based augmentation systems.

The term 'abas' signifies ?

Question 196-34 : Airborne based augmentation systems aerial broadcast application systems airborne based augmentation safety airborne based application standards

Admin .from the easa 'detailed theoretical knowledge syllabus and learning objectives' 'abas' means airborne based augmentation systems exemple 428 Airborne based augmentation systems.Airborne based augmentation systems.

The system capable to measure on ground the signal errors transmitted by gnss ?

Question 196-35 : Gbas sbas abas tbas

Admin .the gbas ground segment consists of three or four gbas reference receivers that are sited typically on or near an airport property these reference receivers track the signals from navigation satellites and pass pseudorange measurements and other information relevant to signal health and system performance monitoring to a central processing facility .the central processing facility uses the multiple redundant observations of the pseudoranges to compute estimates of the pseudorange corrections for each satellite signal observed by the reference receivers .the central processing facility also monitors the signal integrity and computes parameters for each satellite that the user may use to determine the availability of the signal in space for a desired level of service and a given satellite geometry . 2609.the differential corrections and integrity information are broadcast to the user exemple 432 Gbas.Gbas.

A sbas satellite based augmentation systems consists of ?

Question 196-36 : 3 elements 2 elements 1 element 4 elements

Admin .3 elements ground infrastructure sbas satellites and sbas airborne receivers exemple 436 3 elements.3 elements.

Frequency band of the sbas data link is ?

Question 196-37 : A signal with the same frequency as gps vhf band of ils and vor systems 962 to 1213 mhz vhf band 108 0 to 111 975 mhz

Admin .sbas = same frequency .the frequency band of the data link is identical to that of the gps signals l1 frequency 1575 42 mhz .take care another question asks for the 'gbas data link frequency band' the answer is vhf band of ils and vor systems exemple 440 A signal with the same frequency as gps.A signal with the same frequency as gps.

Sbas systems improve the performance position accuracy of gnss/gps receivers by ?

Question 196-38 : Providing an additional signals coming from the geostationary satellites providing an additional signals coming from the navigation satellites providing an additional signals to gps receivers reducing the clock errors

Admin .geostationary sbas satellite based augmentation systems satellites broadcast corrections to the standard data broadcast by gps geo orbital satellites in order to improve the accuracy of the solution obtained from the raw gps data the gps solution obtained from the broadcast gps data using a single frequency receiver will typically have an accuracy within about 3 to 5 meters most of the time using sbas corrections this accuracy can be improved to around the 1 meter mark in typical operation .corrections are calculated using a network of accurately surveyed ground based monitoring systems uploaded to the sbas satellites via ground uplink stations and then broadcast by the sbas satellites on the standard 1575 42mhz gps l1 frequency .current sbas system implementations providing freely available broadcast data are the us wide area augmentation system waas the european geostationary navigation overlay service egnos and the japanese multi functional satellite based augmentation service msbas .messages are transmitted from satellites as subframe messages in the same way as navigational data is received from standard gps satellites exemple 444 Providing an additional signals coming from the geostationary satellites.Providing an additional signals coming from the geostationary satellites.

Egnos european geostationary navigation overlay service is a ?

Question 196-39 : Satellite based augmentation systems sbas airborne based augmentation systems abas ground based augmentation systems local area augmentation system laas

Admin .satellite based augmentation systems sbas is sometimes called wide area differential gps wadgps exemple 448 Satellite-based augmentation systems (sbas).Satellite-based augmentation systems (sbas).

Sbas messages are broadcast via ?

Question 196-40 : Geostationary satellites low earth orbit satellites polar orbit satellites medium earth orbit satellites

exemple 452 Geostationary satellites.Geostationary satellites.

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