Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Data compression techniques for use with the SITAN (Sandia Terrain-Aided Navigation) algorithm

Technical Report ·
OSTI ID:6989666
Data compression algorithms are becoming an important part of systems that use digital terrain elevation data (DTED) such as moving map display systems, terrain-following and terrain-avoidance systems, and terrain-aided navigation systems. This paper describes and compares two DTED compression techniques for use with the Sandia Terrain-Aided Navigation (SITAN) algorithm designed specifically for operation in a land vehicle. One technique uses the two-dimensional discrete cosine transformation (2-D DCT) combined with linear scaling; the other uses data decimation in the spatial domain, followed by a differential pulse code modulation operation on the decimated spatial data. These techniques are designed to minimize the DTED reconstruction error for a given compression ratio and are targeted for implementation in the Motorola 68000-based Sandia Aerospace Computer. This paper presents a description of the DTED and its use by the SITAN algorithm. Also, background information concerning the 2-D DCT is presented, followed by a description of the two data compression algorithms. Experimental results are presented which show the magnitude of reconstruction errors for various sets of DTED and various compression ratios. Finally, the effect of reconstruction errors on SITAN performance is presented. 11 refs., 35 figs., 2 tabs.
Research Organization:
Sandia National Labs., Albuquerque, NM (USA)
DOE Contract Number:
AC04-76DP00789
OSTI ID:
6989666
Report Number(s):
SAND-86-0827; ON: DE87003782
Country of Publication:
United States
Language:
English