NavCom SF-3040 Rev.F - Manual (Page 217)

SF-3040 Product User Guide
– Rev. F
Glossary-215
WGS-84 (World Geodetic System 1984) the current
standard datum for global positioning and surveying.
The WGS-84 is based on the GRS-80 ellipsoid.
Y-code the name given to encrypted P-code when
the U.S. Department of Defense uses selective
availability