APRS GPS Error Plot

Bob Bruninga, WB4APR, US Naval Academy Satellite Lab, Annapolis, MD


Precise Positioning Service is for the DOD only. Only Standard Positioning Service (SPS) is available to the public. With SPS, 100 meter accuracy is observed 95% of the time. The following plot shows SPS information gathered at USNA over a 6 hour period. Notice the brief 4 minute excursion over 1/2 mile at 14 knots for our fixed building!



javAPRS Commands (Case Insensitive)
U or D
zooms up/down (you may also use PGup/dn)
L, S, or M
List stations, Show Status or Messages to Java console
CTRL or ALT-click
Centers or Zooms map on clicked location
Arrow keys
scrolls map


APRS Homepage
Satellite Ground Station

The Naval Academy is a registered user of APRS and WinAPRS. The purpose of this web page is to show several applications currently in use at this site and should not be considered as an advertisement or an endorsement of any commercial product.