The Navy Tessellated Spheroid Map Projection System: A Comprehensive Definition.
Abstract
This report describes a map projection model, called the Tessellated Spheroid (TS), which provides a seamless, global framework in which to store scanned chart data and, potentially, other types of spatial data as well. The Compressed Aeronautical Chart (CAC) is being developed at the Naval Research Laboratory in direct support of tactical Navy and Marine Corps aircraft mission planning systems and digital moving map systems. Aircraft programs that currently utilize the CAC database include the AV-8B Harrier, F/A-18 Hornet, and V-22 Osprey. There has been recent interest in using the TS system to store datasets other than CAC: the newly formed A-X program (which replaced the A-12 program) is interested in storing the Defense Mapping Agency Digital Landmass System data in the TS model; other programs have shown interest in storing scanned nautical charts and satellite imagery in the TS system and, possibly, compressing that data in the same manner in which the CAC data is compressed. Following a detailed description of the TS model, this report discusses certain issues that must be addressed before the TS model can be applied to databases other than the original CAC. The most pressing issue relates to geographic scale. The CAC database includes six scale-models of chart data: 1:50k (k= thousand), 1:100k, 1:250k, 1:500k, 1:1M (M= million), and 1:2M. All TS parameters are based on the 1:2M scale-model, and any additional scales that are to utilize TS must be an integral divisor of 2,000,000. In addition, the TS segment file naming convention currently stipulates a maximum of 9000 TS segment rows, but scales that are larger than approximately 1:50k have more than 9000 rows. Digital maps, Optical storage, Databases, Data compression.
Document Details
- Document Type
- Technical Report
- Publication Date
- Aug 11, 1993
- Accession Number
- ADA269989
Entities
People
- Lancelot M. Riedlinger
- Maura Connor Lohrenz
- Michael E. Trenchard
- Perry B. Wischow
- Stephanie A. Myrick
Organizations
- United States Naval Research Laboratory