A Universal Fault Diagnosis Platform for Multi-Scale Digital-Coding Metasurfaces

As digital-coding metasurfaces (DCMs) expand in scale and complexity, ensuring operational reliability across diverse architectures has become increasingly critical. We present a universal fault diagnosis platform capable of efficiently locating failures in multi-scale DCM systems. Leveraging inherent phase modulation states, the platform employs a two-stage measurement strategy to distinguish faulty from functional elements with minimal measurements, thus significantly reducing computational complexity. The proposed method is compatible with various quantization resolutions and control modes, and by virtualizing multiple metasurfaces into a equivalent surface, it can be applied to metasurfaces of different scales. Simulations and experimental verifications on 1-bit and 2-bit DCMs confirm high diagnostic accuracy and robustness under varying environmental and positional conditions. The proposed platform requires no auxiliary sensors, supports fully automated operation, and is scalable to large metasurface arrays. This work provides an effective, low-cost solution for maintaining stable operation of next-generation intelligent metasurface systems in communications, sensing, and radar applications.