Development of an Interface for Estimating the GDOP Parameter in the Conceptual Design of Satellite Constellations

This study presents the development and evaluation of an automated user interface comprising a MATLAB code and simulations from Systems Tool Kit (STK) (as one of the leading software packages in orbital mechanics). The user interface aims to calculate the GDOP of various orbital scenarios in an iterative and time-saving manner, which is a common feature in the conceptual satellite constellation design step. GDOP, a key metric for positioning accuracy in satellite constellations, plays a vital role in enhancing the reliability of navigation results. In order to attain more explicit and precise results, inverse GDOP (۱/GDOP) is utilized here. The research involves simulations of ۲۱۰۰ circular satellite constellations assuming two-body problem conditions in three altitudes—۴۰۰, ۸۰۰, and ۱۴۰۰ kilometers—and seven orbital inclinations (۰° to ۹۰° at ۱۵° intervals) following the Walker Delta pattern. The results are validated against manually defined STK scenarios, confirming the reliability and efficiency. It can be concluded that results become more accurate versus higher altitudes, while the higher the inclination, the better the outcomes are. The developed tool demonstrates faster performance than manual methods while maintaining satisfactory performance and offers a valuable positioning and satellite navigation research solution, enabling faster and more reliable calculations.

کلیدواژه ها:

Geometric Dilution of Precision (GDOP) ، Satellite Navigation ، User Interface ، Systems Tool Kit (STK) ، Positioning Accuracy