Part of the International MODIS/AIRS Processing Package (IMAPP)
September 22, 2005: Version 4.0 released
The polar-orbiting Aqua
spacecraft, launched by NASA in May 2002, provides an X-band direct broadcast
service where data from all science instruments is downlinked to the Earth
in near real-time. The AIRS/AMSU/HSB Processing Package for Direct Broadcast allows any
ground station capable of receiving direct broadcast from Aqua to produce
calibrated and geolocated AIRS, AMSU, and HSB Level 1B (calibrated and geolocated
instrument observations) and Level 2 (geophysical retrieval) products . This package
is functionally identical to the operational AIRS/AMSU/HSB software running
at the GSFC DAAC, with
the following additions:
This is a binary-only release for Red Hat Intel Linux and Sun Solaris (SPARC) platforms. No source code is included. This version of the package has been tested on the following platforms:
Red Hat Intel Linux: 7.3, 8.0, Enterprise
Sun Solaris (SPARC): 7, 8, 9
The input expected by the package is Level 0 AIRS,
AMSU, HSB, and GBAD files, defined as reconstructed time-ordered CCSDS packets with
all communication artifacts (including duplicate and bad packets) removed.
This includes PN and Reed Solomon decoding as well as reassembly of the raw
telemetry packets. Processing of the data stream to this stage is the responsibility
of the user. Data in this format is known as a Production Data Set (PDS).
The Direct
Readout Laboratory at NASA GSFC has developed a software application named
RT-STPS
(Real-Time Software Telemetry Processing System), which synchronizes the
data, performs PN and RS decoding and packet reassembly, and writes the output
in PDS format. This package is know to be compatible with Level 0 PDS files
created by RT-STPS. In addition, many X-band ground station vendors supply
processing hardware and/or software that creates compatible Level 0 files.
Installation and Operation
The package is available for download by anonymous FTP at
ftp://ftp.ssec.wisc.edu/pub/IMAPP/AIRS/v4.0/
Please see the
README file for instructions on
installing and running the package. If you are unable to download the package
because of a slow Internet connection, please contact us and we will arrange
to ship the package to you on DVD media. This package is released
under the terms of a NASA GSFC
Software
Release and Usage Agreement.
The format of the AIRS, AMSU, and HSB Level 1B and Level 2 output
files is identical to the format of the equivalent GSFC DAAC files.
The format is HDF-EOS, and all ECS metadata fields are present. Regardless
of the size of the direct broadcast pass, the output files will be split
into standard AIRS 6-minute granules. Therefore the leading and/or trailing
granules created from a direct broadcast pass will contain some missing data.
Credits
This package was developed at NASA Jet Propulsion Laboratory by Quyen Nguyen,
Richard Forrister and Evan Manning under NASA RTOP 622-40-45-03 in support
of the AIRS Project at NASA Jet Propulsion Laboratory under NASA NPO-21132.
This package is supported at SSEC by Liam Gumley, Allen Huang,
and Kathy Strabala, as part of the International MODIS/AIRS
Processing Package (IMAPP). IMAPP is funded by NASA under grant NAG5-13402.
Related Links for AIRS/AMSU/HSB
Level 0 data:
Univ.
of Wisconsin | NASA GSFC
Level 1B and Level 2 data:
Univ.
of Wisconsin | GSFC DAAC Data
Pool
AIRS:
Home |
GSFC DAAC |
Algorithm
Theoretical Basis Documents
Aqua spacecraft:
Home | Orbit Tracks | Overpass
Prediction | NORAD TLE orbital
elements