Time Difference Survey System (TDSS).
Abstract
A primary concern of the U.S. Coast Guard is the development of a system of using Loran=C to enable vessels to accomplish precision navigation in harbors, harbor entrances (HHE), and restricted waterways. The need for this system is especially great during periods of low visibility or when more conventional aids to navigation are not available. A visual survey method is the basic approach for a Loran-C Time Difference (TD) grid survey in restricted waterways. The shipboard visual navigation approach relates the surveyed Time Differences (TD's) to the world of the mariners. The results is a set of waypoints (i.e., intersection of two visual ranges) measured in TD's which relate to the actual location of channel edges, shoals, buoys, and other aids to navigation. This report describes the Time Difference Survey System (TDSS) which was developed at the U.S. Coast Guard R&D Center to accurately and efficiently measure, record, and process the TD information. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1981
- Accession Number
- ADA115588
Entities
People
- A. J. Sedlock
- J. P. Lewicki
- T. J. Milne
Organizations
- United States Coast Guard Research & Development Center