Abstract
The growing dependence on satellite communication networks for critical infrastructure operations and secure data exchange has highlighted the urgent necessity for quantum-resistant cryptographic protocols capable of withstanding both conventional and emerging quantum-based attacks. This research provides a detailed examination of how Quantum Key Distribution (QKD) can be integrated into existing satellite communication systems, introducing a novel risk assessment model to evaluate the real-world feasibility of deploying space-based quantum cryptography. The study develops a mathematical framework that accounts for photon transmission losses, atmospheric disturbances, and orbital mechanics, analyzing their impact on quantum key generation rates in both Low Earth Orbit (LEO) and Geostationary Earth Orbit (GEO) satellite configurations. Using theoretical modeling and extensive simulations, the research demonstrates that hybrid systems combining QKD with classical communication protocols can achieve secure key generation rates of up to 1.2 kilobits per second under favorable atmospheric conditions, while maintaining quantum bit error rates below 8\%. Critical performance benchmarks are identified, including a minimum satellite altitude of 550 kilometers required to establish stable quantum channels with practical key distribution efficiency. The proposed risk assessment framework integrates factors such as atmospheric turbulence, orbital constraints, and limitations in ground station infrastructure, offering a quantitative basis for strategic deployment decisions. Findings indicate that while current technologies enable small-scale quantum satellite networks with clear security advantages over traditional encryption, broader adoption will require significant advances in infrastructure, engineering, and cost-efficiency to achieve commercial scalability.