Research

My research interests span Low Earth Orbit (LEO) satellites Precise Orbit Determination (POD), and computational navigation systems. I specialize in developing algorithms for GNSS-based atmospheric sensing, automated satellite data processing, and intelligent positioning systems. My work bridges theoretical research with practical implementations, contributing to advances in navigation systems. Currently, I focus on solving real-world challenges in autonomous navigation, and machine learning applications.

An Algorithm for Estimating Thermospheric Density Using LEO Dual-Frequency GNSS Receivers: Design, Uncertainty Analysis, and Validation

Jian Yao, Stefan M. Codrescu, Faisal Wahabu, Mihail V. Codrescu, and Stephen Leroy

38th International Technical Meeting of the Satellite Division of The Institute of Navigation (ION GNSS+ 2025)

Developed and validated a novel algorithm for estimating thermospheric density using dual-frequency GNSS receivers on Low Earth Orbit (LEO) satellites. The algorithm addresses challenges in satellite drag modeling by extracting along-track total acceleration from precise orbit determination, computing air-drag acceleration, and introducing separate drag coefficients for satellite main body and solar panels. Demonstrated successful validation using COSMIC-2 satellites with comparison against the Coupled Thermosphere Ionosphere Plasmasphere Electrodynamics (CTIPe) model during geomagnetic storm conditions in February 2022.

September 2025

Indoor Navigation with AR using Visual-Based Localization and RSSI

Combined Visual-Based Localization with Received Signal Strength Indicator for an Indoor Navigation Application. Explored Bayesian Filters for Sensor Fusion. Incorporated multiuser experience where an indoor space is scanned for its visual & RSSI landmarks, and this data is stored in Firebase and it's retrievable for all other users within the same space for navigation.

May 2021