RAS Toolbox

RAS Software Toolbox consists of various functional modules and main programs that perform mathematical and data processing services frequently encountered in GPS RINEX and SP3 related engineering calculations.

The GPS RAS Toolbox library of m-file modules and main programs are intended for multipurpose use as

Simulation tool. It can generate a realistic simulation for numerous aspects of RINEX and SP3 applications by using directly the existent main programs.
Performance analysis tool. It can execute a variety of data analysis functions using Yuma or SEM almanac format, RINEX GPS navigation and observation files format, and SP3 GPS orbit data format.
A starting point for user’s GPS RINEX and SP3 related applications. The user can modify existent m-files to suit a specific application without the need of implementing elementary building blocks that are included in this toolbox.

Here is a summary of the most significant features of RAS Toolbox software library:

all m-file modules and programs are written in MATLAB language/environment,
all m-file modules are free of input/output statements (except, of course, for those utilities that require printed output/graph, if any),
all m-file modules are provided with detailed documentation, including scope, usage, and description of parameters, remarks/notes, references, external MATLAB modules used, and date of last update.

Overall, there are more about 40 m-files (modules and main programs), and about 50 input and output data files. In addition, all main programs have test examples using default data or specified input data files.

The functions included in the GPS RAS Toolbox are divided in several categories as follows.

General data processing for (Yuma, SEM, SP3, RINEX) data files. This category includes the reading and decoding (Yuma, SEM, SP3, RINEX) data files, and creating special data files containing reduced almanac, ephemeris and satellite position/velocity data. In addition, several general graphing main programs are including for executing plots related to almanac and ephemeris data.
GPS satellite orbit data analysis. There are six comparison main programs that compare processed GPS satellite position and velocity data from two different sources, namely two Yuma/SEM almanacs data sets, two ephemeris data sets, two SP3 format precise orbits data sets, Yuma/SEM almanac and ephemeris data sets, comparison of Yuma/SEM almanac and SP3 format precise orbit data, and comparison of ephemeris data and SP3 format precise orbit data.
User position determination. There are 3 user determination main programs using RINEX information decoded by general data processing programs as follows: a) determination of user position based on RINEX 2 navigation and observation data when no atmospheric corrections are applied, b) determination of user position based on RINEX 2 navigation and observation data when iono and tropo corrections are applied, c) determination of user position based on RINEX 2 navigation and observation data when dual frequency P-code iono and tropo corrections are applied.
Utility modules. This category includes about 20 modules performing basic mathematical operations related to coordinate transformation, user position determination, setting GPS constants, iono and tropo computations, elevation and azimuth angles, satellite position and velocity computations, mathematical statistics.

Schematic Data flow for the GPS orbit comparison programs.