A fragment-based encryption and compression scheme for secure air-to-ground data transmission

With the rapid development of civil aviation digitalization and the increasing demand for real-time communication between airborne systems and ground control stations, the security and efficiency of air-to-ground (ATG) data transmission has become a critical issue. Traditional data transmission frameworks are often challenged by limited airborne bandwidth, inconsistent encryption mechanisms, and lack of structured field-level compression. This paper proposes a secure and adaptive ATG transmission framework which integrates frame-level encryption and field-based compression strategies. The proposed method supports adaptive encryption strength based on real-time bandwidth detection and ensures interoperability of compressed fields (IP, UDP, MAC, Payload) across airborne terminal systems and ground stations. This paper also introduces a protocol structure to encapsulate XOR-encrypted and compressed frames, ensuring consistency with avionics communication protocols and data parsing mechanisms. Simulation and analysis confirm the feasibility of our approach under different bandwidth conditions.