Random Space-Time Sampling and Reconstruction of Sparse Bandlimited Graph Diffusion Field
摘要
In this work, we investigate the sampling and reconstruction of spectrally s-sparse bandlimited graph signals governed by heat diffusion processes. We propose a random space-time sampling regime, referred to as randomized dynamical sampling, where a small subset of space-time nodes is randomly selected at each time step based on a probability distribution. To analyze the recovery problem, we establish a rigorous mathematical framework by introducing the parameter the dynamic spectral graph weighted coherence. This key parameter governs the number of space-time samples needed for stable recovery and extends the idea of variable density sampling to the context of dynamical systems. By optimizing the sampling probability distribution, we show that as few as