Channel Capacity Under General Nonuniform Sampling
Source: Stanford University
This paper develops the fundamental capacity limits of a sampled analog channel under a sub-Nyquist sampling rate constraint. In particular, the authors derive the capacity of sampled analog channels over a general class of time-preserving sampling methods including irregular non-uniform sampling. Their results indicate that the optimal sampling structures extract out the set of frequencies that exhibits the highest SNR among all spectral sets of support size equal to the sampling rate. The capacity under sub-Nyquist sampling can be attained through filter-bank sampling, or through a single branch of modulation and filtering followed by uniform sampling.