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NAVSTAR Global Positioning System Surveying


Quiz Questions

1.The NAVSTAR GPS is a passive, satellite-based, navigation system operated and maintained by the ___________________.
Department of Defense
Department of Navigation
2. A GPS receiver is simply a range measurement device, distances are measured between the receiver antenna and the satellites, and the position is determined from the intersections of the range vectors.
True
False
3.There are basically two general operating modes from which GPS derived positions can be obtained: ____________ positioning and _________________ or differential positioning.
Absolute, relative
Absolute, Circulative
4.Two levels of relative positioning accuracy may be obtained from the NAVSTAR GPS. These are called the (1) Standard Positioning Service (SPS) and (2) Precise Positioning Service (PPS).
True
False
5.The _____________________ consists of all GPS satellites in orbit.
Space segment
Control segment
6.The control segment represents the ground-based receiver units that process the NAVSTAR satellite signals and arrive at a position of the user.
True
False
7.The modulated C/A- and P-codes are referred to as pseudo-random noise (PRN).
True
False
8.A pseudo-range is the time advance between the satellite clock and the receiver clock, as determined from C/A- or P-code pulses.
True
False
9.The broadcast ephemerides are actually predicted satellite positions broadcast within the navigation message that are transmitted from the satellites in real time.
True
False
10.GPS can be used for _________________ high-order geodetic control densification.
Narrow area
Wide area
11.A _______ is an effective means to correlate and store diverse information on natural or man-made characteristics of geographic positions.
GPS
GIS
12.Orthometric elevations are those corresponding to the earth’s irregular geoidal surface.
True
False
13._____________ positioning involves the use of only a single passive receiver at one station location to collect data from multiple satellites in order to determine the station’s location.
Absolute
Relative
14.3D GPS accuracy measurements are not commonly expressed by Spherical Error Probable, or SEP.
True
False
15.Differential or relative positioning requires at least two receivers set up at two stations (usually one is known) to collect satellite data simultaneously in order to determine coordinate differences.
True
False
16.________________ surveying is the most widely used differential technique for control and geodetic surveying.
Static
Rapid static
17.Psuedo kinematic involves collecting data for several minutes (1-2 min.) at each station after a period of initialization to gain the integers.
True
False
18.Which carrier phase tracking techniques are used in medium accuracy control surveys?
Stop & Go Kinematic
Pseudo Kinematic
RTK/OTF Kinematic
All the above
19.There are two basic types of GPS receivers: code phase and carrier phase receivers.
True
False
20.Receivers which utilize the ________________ technique are only able to obtain one-half of the signal wave length on the L2 during anti-spoofing and have a high 30-dB loss.
Squaring
Cross correlation
P-W correlation
21.There are two general types of carrier phase receivers _________________________
Single & dual frequencies
Dual & multiple frequencies
22.The first step in planning GPS control surveys is to determine the ultimate accuracy requirements.
True
False
23.The minimum number of receivers required to perform a differential GPS survey is _____________.
One
Two
Three
24.PDOP is simply GDOP less the time bias.
True
False
25.In general, GDOP and PDOP values should be less than 0.6 for a reliable solution.
True
False
26.Vertical Dilution of Precision (VDOP) is a measure of vertical positioning accuracy (due mainly to satellite geometry) relative to the precision of the measurements used to determine the position.
True
False
27.________________ Receivers can correct GPS measurements for ionospheres-based range errors.
Single-frequency
Dual-frequency
28.Height of instrument (HI) refers to the correct measurement of the distance of the GPS antenna below the reference monument over which it has been placed.
True
False
29.GPS Pathfinder Office is typical of software designed to manage and process data collected by mapping grade GPS receivers.
True
False
30.The FAA’s WAAS is a GPS-based navigation and landing system that will provide precision guidance to aircraft at thousands of airports and airstrips where there is currently no precision landing capability.
True
False
31.__________________ is proprietary system operated by the Fugro group.
OmniSTAR
FAA’s WAAS
32._______________GPS surveying is perhaps the most common method of densifying project network control.
Non-static
Static
33.SCOUT is another free differential GPS baseline processing service that operates similarly to OPUS.
True
False
34.Stop-and-go surveying is performed in a different way when compared to a conventional electronic total station radial survey.
True
False
35.The carrier “beat” phase observable is the phase of the signal remaining after the internal oscillated frequency generated in the receiver is differenced from the incoming carrier signal of the satellite.
True
False