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NASA’s Crustal Dynamics Data Information System (CDDIS) archive contains GNSS data from the global network of permanent GNSS receivers supporting the IGS operating at a 30-second sampling rate and containing one hour of data. IGS analysis centers retrieve these hourly data files to produce IGS "rapid" and "ultra-rapid" products such as satellite ephemerides, clocks, and Earth rotation parameters, which are then submitted to CDDIS. The IGS Analysis Center Coordinator generates a daily, combined, rapid product with a 17-hour latency. The ultra-rapid (predicted) orbit and clock products are generated four times per day.

IGS stations forward hourly 30-second GNSS data in compressed RINEX format to CDDIS within minutes following the end of the hour. At the present time, an average of 360 sites are archived in this fashion each day for availability to the global science community. Hourly GNSS data available in RINEX V2 format use the mmmmDDDH.YYt.gz filename convention and are in gzipped format, as of December 1, 2020. Files received prior to this date use the mmmmDDDH.YYt.Z filename convention and are in a Unix compressed format. Starting with data from 2016, all hourly GNSS data in RINEX V3 that use the RINEX V3 filenaming convention and the gzip compression format are archived with data in RINEX V2 format, in subdirectories in the /gnss/data/hourly area.

At the close of the UTC day, the station operators incorporate individual hourly GNSS data into a full day's data file, submitted to the CDDIS and made available in the daily GNSS data directories. These hourly files are stored in hourly subdirectories within the file system.

The starting directory for these files is:

https://cddis.nasa.gov/archive/gnss/data/hourly/

Append the following directory and file names to the starting directory using the format codes in the links below.

RINEX V2 Format

YYYY/DDD/HH/mmmmDDDH.YYt.gz

RINEX V2 File Name Codes

CodeMeaning
YYYY4-digit year
DDD3-digit day of year
HH2-digit hour of day (00, 01, ..., 23)
mmmm4-character site monument name
H1-character hour of day (a = 00, b = 01, ..., x = 23)
YY2-digit year
ttype of data:

d = Hatanaka-compressed observation data(doi:10.5067/GNSS/gnss_hourly_d_001)
g = GLONASS broadcast ephemeris data(doi:10.5067/GNSS/gnss_hourly_g_001)
m = compressed meteorological data(doi:10.5067/GNSS/gnss_hourly_m_001)
n = GPS broadcast ephemeris data(doi:10.5067/GNSS/gnss_hourly_n_001)
 
.gzCompressed file

RINEX V3 Format

YYYY/DDD/HH/XXXXMRCCC_K_YYYYDDDHHMM_01H_30S_tt.FFF.gz

RINEX V3 File Name Codes

CodeMeaning
YYYY4-digit year
DDD3-digit day of year
HH2-digit hour of day (00, 01, ..., 23)
XXXX4-character IGS station name
Mmonument or marker number (0-9)
Rreceiver number (0-9)
CCCISO country code
KData source:

R = From Receiver data using vendor or other software
S = From data Stream (RTCM or other)
U = Unknown
DDD3-digit day of year
HH2-digit hour (00, 01, ..., 23)
MM2-digit minute
tttype of data:

GO = GPS Observation data
RO = GLONASS Observation data
EO = Galileo Observation data
JO = QZSS Observation data
CO = BDS Observation data
IO = IRNSS Observation data
SO = SBAS Observation data
MO = Mixed Observation data(doi:10.5067/GNSS/gnss_hourly_o_001)
GN = GPS Navigation data(doi:10.5067/GNSS/gnss_hourly_n_001)
RN = GLONASS Navigation data(doi:10.5067/GNSS/gnss_hourly_g_001)
EN = Galileo Navigation data(doi:10.5067/GNSS/gnss_hourly_l_001)
JN = QZSS Navigation data(doi:10.5067/GNSS/gnss_hourly_q_001)
CN = BDS Navigation data(doi:10.5067/GNSS/gnss_hourly_f_001)
IN = IRNSS Navigation data(doi:10.5067/GNSS/gnss_hourly_i_001)
SN = SBAS Navigation data(doi:10.5067/GNSS/gnss_hourly_h_001)
MN = Navigation data (All GNSS Constellations)(doi:10.5067/GNSS/gnss_hourly_x_001)
MM = Meteorological Observation(doi:10.5067/GNSS/gnss_hourly_m_001)
FFFFile format:

rnx = RINEX
crx = Hatanaka Compressed RINEX
.gzCompressed file