readme

gps源代码

$Id: README 705 2007-07-25 18:49:15Z pben $

The following is excerpted from the GPSTk web site at http://www.gpstk.org/. 

What is GPSTk?
--------------

The goal of the GPSTk project is to provide a world class, open source 
computing suite to the satellite navigation community. It is our hope that the
GPSTk will empower its users to perform new research and create new 
applications.

GPS users employ practically every computational architecture and operating 
system. Therefore the design of the GPSTk suite is as platform-independent as 
possible. Platform independence is achieved through use of the ANSI-standard 
C++ programming language. The principles of object-oriented programming are 
used throughout the GPSTk code base in order to ensure that the code is 
modular, extensible and maintainable.

The GPSTk suite consists of a core ibrary and a set of applications. The 
library provides a wide array of functions that solve processing problems 
associated with GPS such as processing or using RINEX. The library is the 
basis for the more advanced applications distributed as part of the GPSTk 
suite.

The GPSTk is sponsored by Space and Geophysics Laboratory, within the Applied 
Research Laboratories at the University of Texas at Austin (ARL:UT). GPSTk is
the by-product of GPS research conducted at ARL:UT since before the first 
satellite launched in 1978; it is the combined effort of many software 
engineers and scientists. In 2003 the research staff at ARL:UT decided to 
open source much of their basic GPS processing software as the GPSTk.


GPSTk Library
-------------

The GPSTk library provides a number of models and algorithms found in GPS 
textbooks and classic papers, such as solving for the user position, or 
estimating atmospheric refraction. Common formats are supported as well, such 
as RINEX or SP-3. There are several categories of functions in the GPSTk 
library:

   1. GPS time. Conversion among time representations such as MJD, GPS week 
      and seconds of week, and many others.

   2. Ephemeris calculations. Position and clock interpolation for both
      broadcast and precise ephemerides.

   3. Atmospheric delay models. Includes ionosphere and troposphere models.

   4. Position solution. Includes an implementation of a Receiver Autonomous 
      Integrity Monitoring algorithm.

   5. Mathematics. Includes Matrix and Vector implementations, as well as 
      interpolation and numerical integration.

   6. GNSS data structure. Data structures that contain observations mapped
      to satellites.

   7. Application framework. Includes processing command lines options, 
      providing interactive help and working with file systems.

A more detailed description of the functionality provided by the GPSTk library can be found in the Doxygen documentation.


GPSTk Applications
------------------

The library is the foundation for applications within the GPSTk suite. Many 
such applications are utilities necessary for advanced research and 
development. For example the GPSTk utility DiscFix fixes cycle slips. Some 
applications implement algorithms described in research papers. The TECMap 
application is an example of an application that creates models of the 
ionosphere, based on models published by a number of researchers. To date 
GPSTk applications fall into the following categories.

   1. Ionosphere modeling. TEC calculation, receiver bias estimation.

   2. Residual analysis. Computation of pseudorange observations residuals, 
      and comparison between the precise and broadcast ephemerides.

   3. RINEX file manipulation. Differencing, mergins and clipping RINEX files.

   4. Interactive analysis. Bindings to Python.


License
-------

The source code provided by the GPSTk is distributed under the GNU LGPL 
(http://www.gnu.org/copyleft/lesser.html). This license gives all users the 
right to use and redistribute the code. Users of the GPSTk are not required 
to open their source, according to the LGPL. This makes the GPSTk a practical 
choice for commercial projects.

Contact Info
------------
The GPSTk is a collaborative effort. However, you can email to 
[e-mail] or contact one of the CoreTeam members
(http://www.gpstk.org/bin/view/Development/CoreTeam).