Vayudoot Aviation

1. The orbital height and inclination of the NAVSTAR/GPS constellation are

19099 km, 65°

20180 km, 55°

20180 km, 65°

2. Position fixing by satellite is by means of

simultaneous ranges from a number of satellites.

range and bearing from each known satellite's position

simultaneous bearings from a number of satellites

3. The DGPS is

the time difference between the transmission of the satellite's coded signal and the time that it is received at the aircraft

the correction applied to the 'raw' GPS position to obtain a more precise position.

the time difference between the satellite and the aircraft GPS unit transmitting the same code point on the signal

4. The US DoD degrades GPS accuracy

to prevent 100% reliance on a system which may have to be interrupted for military purposes at a moment's notice.

to protect US national security

to protect the DoD copyright

5. The GPS can

indicate two-dimension positions or position lines in the horizontal plane.

provide two-dimension and three-dimension positions

only provide position in latitude and longitude

6. The model of the earth used for NAVSTAR/GPS is

WGS84

WGS90

PZ90

7. NAVSTAR/GPS operates in the _______ band and the receiver determines position by ________

UHF, range position line

UHF, secondary radar principles

SHF, secondary radar principles

8. The reason that the satellites of GPS and GLONASS do not collide is

the GPS satellite orbits are 1200 km higher than the GLONASS orbits

GLONASS has only three orbital planes while GPS has six orbital planes.

the GPS orbit is at 55° to the equator while the GLONASS is at 60°

9. The accuracy of range measurement of satellite to GPS receiver is

derived from accurate timepieces in the satellite and the aircraft's GPS receiver.

seriously eroded during periods of anomalous propagation in an inversion

seriously reduced during periods of sunspot activity

10. The minimum number of satellites required for a 3D fix is

4

3

5

11. Satellites used in GNSS< orbit the earth

once in 24 hours.

once in twelve hours

once in eight hours

12. The GPS transmission frequency which can be used by civil aircraft is

1575.42 MHz in the L-band.

2227.5 MHz in the S-band.

1227.6.5MHz in the L-band.

13. Satellite geometry error is greatest when

satellites are closest together

satellites are nearest the horizon.

satellites are spaced well apart

14. The NAVSTAR/GPS operational constellation comprises ___________ satellites

21

12

24

15. It may be claimed that GNSS has the advantage over other air navigation systems in that it

has no possible input by the pilot

is basically a military-based system made available to civil users with solar-powered satellites which have an infinite life.

is entirely space-based.

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