GPS Timing Data and Information

Coordinated Universal Time (UTC) Time Step (Leap Second)

Dual-frequency GPS Data in RINEX format from the CDDIS data ftp server

1. Yesterday's RINEX observation files for USNO receivers (in UNIX compressed format)
2. Note: This data ftp service and these receivers are not controlled by USNO
3. RINEX format conversion code (in C): to CGGTTS format and to CGGTTS and USNO formats

Timing Data for Individual GPS Satellites (Single frequency C/A code)

• USNO Format format explanation

1. Most recent 1 Day
2. Most recent 7 Days    [UNIX compressed format]   [PC zipped format]
3. Most recent 30 Days  [UNIX compressed format]   [PC zipped format]

• CGGTTS Format (Common View) format explanation

1. Most recent 1 Day
2. Most recent 7 Days   [UNIX compressed format]  [PC zipped format]
3. Most recent 30 Days [UNIX compressed format] [PC zipped format]

• GPS Time vs. UTC via USNO Master Clock

1. Most recent 30 Days
2. Most recent 180 days

Notice Advisories to NAVSTAR Users (NANUs)

• Visit the US Coast Guard page for constellation info and recent NANUs

1. Most Recently Issued NANUs
2. Searchable Archive of Current Year NANUs
3. Archive of NANUs, Almanacs, and OPS Advisories, from 1997 to present
4. Current Constellation Status, Planned & Recent Outages

General GPS Information

• GPS System Description
• Constellation Information
  • Current Satellites
• Satellite Health Codes
• GPS Time Transfer Information

Links to Other GPS Data Sources

• CDDIS GPS Archive from NASA's CDDIS ftp server
• The International GNSS Service (IGS)
• GPS Almanacs from U.S. Coast Guard NAVCEN
• GPS, Beidou, Galileo, Glonass, and WAAS NORAD Orbital Elements
• NOAA's Space Environmental Data for navigational systems