Fundamentals of Surveying (FS) Practice Exam

What is the maximum number of CORS that OPUS Static can use to process a GPS observation file?

1. 1

2. 3

3. 5

4. 7

The correct answer is: 3

The maximum number of CORS (Continuously Operating Reference Stations) that OPUS Static can utilize to process a GPS observation file is three. This limitation is in place to ensure accurate and reliable adjustments during the processing of GPS data. OPUS Static is a service provided by the National Geodetic Survey to derive precise positions from GPS observations. When processing, it employs data from multiple CORS to provide a more robust solution by minimizing potential errors and improving the accuracy of the computed position. By using three CORS, OPUS can effectively perform multipath mitigation and better correct for atmospheric errors and satellite orbit inaccuracies. Using fewer than three CORS may not provide sufficient data for high-accuracy applications, while more than three is not supported by the OPUS Static processing model. Hence, the choice of three aligns with best practices in enhancing position accuracy in GPS surveying contexts.