Question

1. Define the terms "geodetic height", "geoidal height", and "orthometric height", present the equation that expresses the relationship between the geodetic height and orthometric height, and state which one these heights are measured by GNSS survey method.

2. What are the geocentric coordinates in meters of a station which has a latitude of 44°53′52.1918′′ N, a longitude of 68°40′07.3487′′ W and height of 130.405 m (use the WGS84 ellipsoidal parameters)?

3. The geodetic heights of two stations are 324.685 m and 309.879 m, and their orthometric heights are 356.496 m and 341.707 m, respectively. These stations have model-derived geoid heights of −31.828 and −31.836, respectively. What is the orthometric height of a station with a GNSS measured height of 305.645 m and a model-derived geoid height of −31.802 m?

4. A GNSS survey has a reported error of ±(12mm + 2ppm) at a 95% probability. What is the error for a control baseline with a length of 4 miles at the 95% probability?

Answer 1