Mutual Information for Electromagnetic Information Theory Based on Random Fields

Traditional channel capacity based on the discrete spatial dimensions mismatches continuous electromagnetic fields. For wireless communication system in a limited region, discretization may results information loss because field can not be perfectly recovered from sampling points. Therefore, theory spatially fields becomes necessary to reveal fundamental theoretical bound of systems. In this paper, we propose analyzing schemes for performance limit between transceivers. Specifically, model process two regions by random Then, white noise model, use Mercer expansion derive mutual source and destination. close-form expression, an analytic method is introduced autocorrelation functions with rational spectrum. Moreover, Fredholm determinant used general provide numerical calculation scheme. Further works extend colored discuss under it. Finally, build ideal infinite-length destination which shows strong correpsondence time-domain classical theory. The are derived through spectral density.