The trends/ variations of Ionospheric parameters (hmF2, foF2) between observatory and International Reference Ionosphere web model values

(GNSS) Global Navigation Satellite System is the rising technology of times to come, which has a lot of challenges for its precision and errors. The main contributor in the GNSS signal error is the ionosphere in which the GNSS signal is badly affected by Ionospheric layers containing different amount of TEC. The F layer of the ionosphere is more dominant particularly the F2 layer which is present round the clock. The height of F2 layer and critical frequency of F2 layer is very important as maximum electron density (Nm) is calculated by critical frequency of F2 layer by formula 1.24∗10⁁10foF2. Therefore We have drawn comparison between the International Reference Ionosphere and the Observatory values of Islamabad region. The International Reference Ionosphere is an international web model is being looked after by Committee on Space Research and the International Union of Radio Science. The COSPAR and URSI are working since late sixties to develop an inospheric empirical model based on all existing sources of data. Many progressively enhanced editions of the model have been released. International Reference Ionosphere gives readings of many parameters including electron density, solar zenith angle, total electron content, height of F2 layer, critical frequency of F2 layer at an altitude ranging between 50 km–2000 km, but we are interested in height of F2 layer and critical frequency of F2 layer for making comparison between the International Reference Ionosphere values & observatory values. Therefore in this paper a little back ground of the International Reference Ionosphere model and drawn comparison between the Ionospheric parameters i:e (hmF2, foF2) of real time observatory and International Reference Ionosphere web model values of Islamabad region with a view to analyze the difference/variations in the values obtained from observatory and web model.