Developing k-out-of-n: G multilevel system with mixed redundancy strategy to protect DSP code using simplified swarm optimization

Mitigating transient faults in aerospace software, particularly radiation-induced Single-Event Upsets (SEUs) affecting Digital Signal Processor (DSP) code, remains a critical challenge. Redundancy strategies are among the most effective approaches to address SEUs. This study introduces a novel program architecture based on a k-out-of-n: G system, incorporating mixed redundancy strategies to enhance the reliability of DSP code. As DSP code operates within a multilevel system, this is the first study to integrate a multilevel system with k-out-of-n: G modules using mixed redundancy strategies. This integration allows for diverse combinations of subsystem reliability calculations, making it strategically advantageous. To evaluate the reliability of redundant program modules in each subsystem, a modular continuous-time Markov chain (CTMC) was applied. To address the extensive combinations of k and n values alongside redundancy strategies, simplified swarm optimization (SSO) was employed for multilevel encoding and near-optimal solution discovery. Experiments on the Fast Fourier Transformation (FFT) program demonstrated the method's effectiveness compared to state-of-the-art approaches, further verifying its scalability and capability to establish a more stable and highly reliable DSP code architecture for large-scale problems.