Surveying Equipment and Technology Flashcards
6 cards from real FUNDAMENTAL SURVEYING practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Surveying Equipment and Technology flashcards as text
What is 'multipath error' in GPS surveying?
Answer: Signal reflections from surfaces causing the receiver to receive delayed copies of the signal, degrading accuracy
Multipath occurs when GPS signals reflect off buildings, terrain, or vehicles before reaching the antenna, causing range measurement errors.
What is the typical frequency of GPS L1 signal?
Answer: 1575.42 MHz
The GPS L1 frequency is 1575.42 MHz and carries both the C/A code (civilian) and P(Y) code (military), as well as the navigation message.
What is 'integer ambiguity resolution' in carrier-phase GNSS?
Answer: Determining the exact number of full wavelengths in the carrier-phase measurement between satellite and receiver
Integer ambiguity resolution determines the unknown whole-number wavelength count in the carrier-phase observable, which is required for centimeter-level GPS positioning.
What does 'IMU' stand for and how is it used in mobile mapping?
Answer: Inertial Measurement Unit — provides orientation and acceleration data to bridge GNSS gaps and aid positioning
An IMU (Inertial Measurement Unit) measures angular rates and accelerations, providing orientation and helping maintain position during GNSS outages in mobile mapping systems.
What is the purpose of an 'anti-vibration mount' on a survey prism pole?
Answer: To isolate the GNSS antenna from ground vibrations for better signal tracking
GNSS antenna mounts may use vibration isolation to reduce the effect of mechanical vibrations on signal tracking, particularly in mobile or machine-control applications.
What is 'scan registration' in terrestrial LiDAR scanning?
Answer: The process of aligning multiple scan positions into a single unified coordinate system
Scan registration combines overlapping point clouds from different scanner positions into one coherent coordinate system using targets or cloud-to-cloud matching.