GISP GPS and Field Data Collection

Question 1

What is the minimum number of GPS satellites required to calculate a 3D position fix (latitude, longitude, and elevation)?

Accepted Answer

4

Answer

2

Answer

3

Answer

6

Question 2

Differential GPS (DGPS) improves positional accuracy by:

Accepted Answer

Applying correction signals from a stationary base station at a known location

Answer

Using more satellite signals simultaneously

Answer

Processing data in dual-frequency mode

Answer

Averaging multiple position readings over time

Question 3

Which GPS error source results from signals bouncing off nearby buildings, vehicles, or terrain before reaching the receiver antenna?

Accepted Answer

Multipath error

Answer

Ionospheric delay

Answer

Ephemeris error

Answer

Selective Availability

Question 4

What does Dilution of Precision (DOP) measure in GPS surveys?

Accepted Answer

The geometric quality of available satellite configuration affecting positional accuracy

Answer

The signal strength of individual satellites

Answer

The time required to achieve a satellite fix

Answer

The amount of atmospheric signal delay

Question 5

Real-Time Kinematic (RTK) GPS achieves centimeter-level accuracy by:

Accepted Answer

Using carrier phase measurements and a real-time base station correction link

Answer

Averaging hundreds of position readings over several hours

Answer

Applying post-processed ionospheric models

Answer

Selecting only satellites above 45-degree elevation

Question 6

In GIS field data collection, which file format is the native exchange format for GNSS waypoints, routes, and tracks commonly supported by handheld GPS devices?

Accepted Answer

GPX (GPS Exchange Format)

Answer

Shapefile (.shp)

Answer

KMZ (Keyhole Markup, compressed)

Answer

GeoJSON