Comparative Analysis of Electric and Chemical Propulsion Effects on Fixed Antenna Pointing Stability in GEO Satellites

ABSTRACT This study investigates the impact of station‐keeping strategies on antenna pointing stability for geostationary (GEO) satellites equipped with either chemical or electric propulsion systems. Two representative satellites—Sat‐C (chemical propulsion) and Sat‐E (electric propulsion)—are simulated in GEO orbit to assess their orbital behaviour and the resulting pointing losses at fixed ground stations. Sat‐C employs a conventional 14‐day station‐keeping cycle, while Sat‐E follows a more frequent 6 + 1 day manoeuvre plan enabled by its low‐thrust electric propulsion system. Antenna pointing losses are quantified for a range of ground antenna sizes (0.5–16 m) operating in Ku‐band (12 GHz) and Ka‐band (25 GHz), with performance assessed over multiple days after station keeping manoeuvre. Results show that electric propulsion yields significantly reduced pointing losses across all antenna sizes. For example, at 5‐m antenna diameter, maximum pointing loss for Sat‐C reaches up to 2.25 dB in Ku‐band and 9.77 dB in Ka‐band, whereas corresponding losses for Sat‐E are limited to 0.18 and 0.79 dB, respectively. The study also evaluates the threshold conditions under which mandatory auto‐tracking becomes necessary, using International Telecommunication Union (ITU) recommendations and guidelines provided by satellite operator ground station specifications. These findings underline the superior stability of electric propulsion platforms in terms of ground link alignment, especially in high‐frequency applications where beamwidths are narrow and pointing errors are critical to link margin.