A Brief Review of Basic GPS Orbit Interpolation Strategies

 
 
Mark S. Schenewerk  
give-em-an-inch.com  
Roeland Park, KS 66205  
published in: GPS Solutions, Volume 6, Number 4.  
 
C code for comparing different techniques for interpolating GPS precise  
ephemerides in SP3 format. Example input and output files are included  
for the atest.c program.  
 
 

How to compile and use the atest.c program (readme.txt)

The main C program, it requires command-line arguments (atest.c)

The only include file needed (atest.h)

Converts hour,min,secs into fractional day (hmsday.c)

Example makefile for gcc compiler on Linux (Makefile)

Use the Neville algorithm for finding interpolated values (polint.c)

Read sp3 files, stores coordinates and time (ScanFile.c)

Find coordinates needed for polint (search.c)

Use Singular Value Decomposition to find coefficients for Trigonometric functions (svdfit.c)

Create Trigonometric functions for ECF files (TrigExt.c)

Create Trigonometric functions for Inertial files (TrigFunc.c)

Convert Year,Month,Day to Modified Julian Date (ymdmjd.c)

Executable file for Windows NT (atest.exe)

Example input SP3 file for ECF frame (ECF_15MI.200)

Example control SP3 file for ECF frame (ECF_5MIN.200)

Example input SP3 file for Inertial frame (IN_15MIN.200)

Example control SP3 file for Inertial frame (IN_5MIN.200)

 
 
 
 
Return to the GPS-TOOLBOX home page