SatTrack (V3.1) ---
A Realtime Satellite Tracking and Orbit Prediction
Program for UNIX/Linux Platforms with X11 Color Graphics
Manfred Bester
August 17, 1995
General description ===================
SatTrack is a realtime satellite tracking and orbit prediction program
with an X11 color world map tracking chart. It has been written in 'C'
language on a Sun/UNIX workstation and provides two different live
displays, for single or multiple satellites, and two different orbit
prediction modes. Cursor controls used in the numerical live displays are
compatible with the VT100 standard, which allows the program to be run
basically from any terminal without the graphics display. If the program is
run from an X Window terminal, the realtime graphics display can be started
up. It will show the location of any number of specified satellites like
the Space Shuttle or the Russian Space Station Mir, featuring the circle of
visibility for any selected spacecraft and for the primary and a number of
secondary ground stations. Also shown are the ground track for the next
three orbits, the black-out zones for communication through the TDRSS
network, Mission Elapsed Time (MET), the terminator, spacecraft lighting
conditions and other details. The world maps are provided in two different
styles with four different sizes each. Program SatTrack is particularly
interesting for the upcoming Shuttle - Mir rendezvous missions.
The present version of SatTrack (V3.1) can track a single satellite
and/or display multiple satellites for a single ground station. It can also
control suitable ground station hardware, like antennas, optical telescopes
and communications equipment with the proper Doppler corrections, and has
an autotrack mode in which it can switch automatically between a number of
specified satellites. For calibration purposes tracking of the Sun and the
Moon are also provided. In the orbit prediction mode SatTrack pre-
calculates passes of satellites over a specified ground station. The
predictions can be run off either interactively or in a batch mode.
The program uses the two-line Keplerian element (TLE) sets generated by the
US Space Command or NASA to run either the SGP4 model for satellites in
low-earth orbit or a simplified model for deep-space objects. Future
releases (V3.5) will have more features, like fast forward mode that will
allow the user to view satellite motions at higher speed, the SDP4 model
for deep-space objects, multiple ground stations and second graphics
display with a fish-eye sky view, and a graphical user interface. Other
program features will allow prediction of GPS coverage and precision (DOP)
as a function of time.
Applications ============
Applications of this software package range from visualizing orbits or
monitoring positions of individual artificial satellites or any groups of
satellites like the GPS system, to satellite system monitoring and space
shuttle mission control objectives and mission planning, as well as full
featured and automated ground station control. A wide number of
applications becomes feasible with the realtime hooks built into modern
Unix systems like Solaris 2.3.
System requirements ===================
SatTrack V3.1 has been successfully compiled on the following
platforms: Sun-3 or Sun-4 (SPARCstation IPC, 5 or 10) with SunOS 4.1.x or
Solaris 2.x, HP Apollo 9000 Series 700, IBM RS-6000, SGI Indigo 2 with IRIX
5.3, DEC Alpha with AXP/OSF, i386-Linux, i386-NetBSD, or i386-FreeBSD, with
X11R5 and X11R6 and various window managers. Only basic X11 and X11 Toolkit
functions have been used to allow the program to be ported easily. SatTrack
requires about 5 MB of disk space and less than 1.5 MB of memory at run
time. With operating systems like Solaris 2.3 or VxWorks 5.1.1, true
realtime performance can be achieved with SatTrack.
How to obtain a copy ====================
Current on-line information on SatTrack can be found on the World Wide
Web page with the following URL:
http://ssl.berkeley.edu/isi_www/sattrack.html
The distribution file 'sattrack.V3.1.1.tar.gz' can be obtained from
this web page as well and has to be uncompressed and unbundled with the
commands tree. The README_MAKE file in the 'src' sub-directory gives brief
instructions to compile the source code. More documentation can be found in
the 'doc' sub-directory.
Copyright =========
Copyright (c) 1992, 1993, 1994, 1995 by Manfred Bester. All Rights
Reserved.
Permission to use this software commercially or to incorporate this
software or parts of it into commercial products may be obtained from the
author, Dr. Manfred Bester, Bester Tracking Systems, P.O. Box 9948, CA
94709, USA.
