Secure Image Transmission: Integrating Image Encryption with Adaptive Modulation and Coding

In terms of forward error correcting (FEC) codes, polar codes are among the most effective. These codes are currently the main candidates for upcoming communication systems and have been adopted in the 5G standard for control channels. This paper presents a secure image transmission framework that integrates chaos-based image encryption with an adaptive transmission approach. The proposed scheme enhances both security and efficiency by leveraging hyperchaotic encryption to ensure strong diffusion and confusion properties through $M$ rounds of encryption, while adaptive Hierarchical Quadrature Amplitude Modulation (HQAM) and adaptive rate polar code improve resilience against transmission impairments. Numerical evaluations demonstrate that the scheme achieves high encryption security, with a vast key space of $2^{744}$, Number of Pixel Change Rate (NPCR) exceeding 98.6% and entropy values close to 8, ensuring randomness. Additionally, the adaptive transmission mechanism enables near-perfect image reconstruction at higher $E_{b}/N_{0}$ values, achieving a Peak Signal-to-Noise Ratio (PSNR) of 48.43 dB at only 2.5 dB and flawless recovery at 4.5 dB and beyond. These results confirm the robustness of the proposed method in securing images while maintaining high fidelity, making it suitable for applications requiring reliable and secure visual data transmission.