Secure Satellite Communication in the Post-Quantum Era: A Lattice-Based Cryptographic Approach

Abstract

Quantum computing poses a looming threat to the cryptographic primitives that secure today's satellite communications. In response, post-quantum cryptography (PQC) has emerged to protect data against future quantum-enabled adversaries. This paper provides a comprehensive analysis of lattice-based PQC methods for secure satellite communication in the post-quantum era. We examine the performance and security of leading lattice-based schemes—including encryption/key-establishment algorithms like CRYSTALS-Kyber and NTRU, and digital signature schemes like CRYSTALS-Dilithium and FALCON—in the context of satellite systems. Real-world benchmark data from peer-reviewed sources are used to evaluate computational efficiency, bandwidth overhead, memory footprint, and energy consumption of these schemes on resource-constrained satellite hardware. We compare lattice-based approaches with classical RSA/ECC and alternative post-quantum techniques (hash-based signatures, code-based encryption), highlighting the favorable trade-offs that have led to lattice-based algorithms becoming primary candidates for standardization. Security analysis is presented to explain the hardness assumptions (e.g., Learning With Errors and NTRU problems) that underpin lattice cryptography, and to assess known cryptanalytic results, resistance to quantum attacks, and remaining security margins. We also discuss practical considerations for deploying lattice-based cryptography on satellites, including integration into existing communication protocols, potential need for hardware acceleration, and strategies for cryptographic agility in long-lived space assets. The results show that lattice-based PQC can be feasibly implemented in satellites with acceptable performance impact, providing strong security against quantum threats and a viable path to future-proof the confidentiality and authenticity of satellite communications.