International Journal of Soft Computing and Engineering (IJSCE)
With the advent of Global Positioning System (GPS), there has been significant change in aircraft navigation. GPS provides position, velocity and time in all space weather conditions. Several errors affect the GPS positional accuracy. The predominant error is ionospheric delay. The ionospheric delay is a function of Total Electron Content (TEC). TEC is one of the physical quantities that can be derived from GPS data and provides an indication of ionospheric variability. TEC along a ray path through the ionosphere can be considered as a measure of ionization.