FS FS - Fundamentals of Surveying GPS and GNSS Technology 2 — Questions and Answers
Question 1: What is RTK in GPS surveying?
- Remote Tracking and Keying
- Real-Time Kinematics (Correct answer)
- Relative Terrain Knowledge
- Radio Transmission Kinetics
Correct answer: Real-Time Kinematics
RTK (Real-Time Kinematics) is a differential GPS technique that delivers centimeter-level accuracy in real time by transmitting corrections from a base station to a rover.
Question 2: What is multipath error in GPS surveying?
- Using multiple satellite constellations simultaneously
- Signal reflecting off surfaces before reaching the antenna (Correct answer)
- Receiving signals from multiple base stations
- Processing observations with multiple algorithms
Correct answer: Signal reflecting off surfaces before reaching the antenna
Multipath error occurs when GPS signals reflect off nearby surfaces such as buildings or water, causing the receiver to process erroneous signal paths.
Question 3: Which atmospheric layer causes the largest GPS signal delay?
- Stratosphere
- Mesosphere
- Troposphere
- Ionosphere (Correct answer)
Correct answer: Ionosphere
The ionosphere causes the largest GPS signal delay because free electrons slow the electromagnetic signal as it passes through.
Question 4: What does PDOP measure in GPS quality assessment?
- Phase Differential Output Position
- Position Dilution of Precision (Correct answer)
- Primary Data Offset Parameter
- Planar Deviation of Position
Correct answer: Position Dilution of Precision
PDOP (Position Dilution of Precision) describes the combined effect of satellite geometry on 3D positional accuracy.
Question 5: GPS satellites orbit Earth at approximately what altitude?
- 200 km
- 2,000 km
- 20,200 km (Correct answer)
- 200,000 km
Correct answer: 20,200 km
GPS satellites orbit at approximately 20,200 km above Earth's surface in medium Earth orbit, providing global coverage.
Question 6: What GNSS constellation is operated by Russia?
- Galileo
- BeiDou
- GLONASS (Correct answer)
- NavIC
Correct answer: GLONASS
GLONASS is Russia's Global Navigation Satellite System constellation, which modern multi-constellation receivers can use alongside GPS.
FS FS - Fundamentals of Surveying GPS and GNSS Technology 2
What is RTK in GPS surveying?