Investigation of the Real-Time Accuracy of the DGPS Method
Abstract
The Real-Time Differential GPS (DGPS) method using the C/A code (not carrier) has the potential to provide positional accuracy to 1-3 meters (1 delta). DGPS is a viable option for positioning tasks in hydrographic surveying. Determination of the real-time DGPS accuracy is the main objective of this study. Accuracy provided by DGPS may deteriorate depending upon operational conditions. Factors influencing DGPS accuracy are discussed. Background of the DGPS method is given including mathematical description, but emphasis is on general concepts and discussion of DGPS error sources. DGPS implementation problems are discussed. Specific realtime data links and their throughput are analyzed. The RTCM-104 standard for meter level DGPS applications and the different DGPS systems used in the study are discussed. The analysis is performed using real-time and post-processed DGPS results. The influence of two major factors affecting the DGPS accuracy: distance from the monitor station and data rate of differential corrections; is investigated. The role of the data rate is evaluated using simulated data rate scenarios. Particular attention is given to the impact of Selective Availability (SA) on meter level DGPS performance during specific days of heavy SA. Real-Time DGPS, C/A Code, Positioning hydrographic surveying, Selective Availability (SA), 1-3 Meters RMS.
Document Details
- Document Type
- Technical Report
- Publication Date
- Nov 01, 1992
- Accession Number
- ADA257692
Entities
People
- Dariusz Lapucha
- Kurtis L. Maynard
Organizations
- Battelle Memorial Institute