TEC computation software (MATLAB):

Single-frequency positioning (MATLAB):

TEC gradient computation (MATLAB)

Kalman filters for positioning with data (sensor) fusion (MATLAB)

SBAS-I positioning (MATLAB)

RINEX 3 reader program (MATLAB)

CSSRG MATLAB source code
Copyright (C) by CSSRG

These programs are free software; you can redistribute it and/or modify it.
In terms of using these programs, users should give acknowledge “This program created by Excellence Center in GNSS and Space Weather, Thailand”.