NyquistSampling and Degrees of Freedom of Electromagnetic Fields
Abstract
A signalspace approach is presented to study the Nyquist sampling and number of degrees of freedom of an electromagnetic field under arbitrary propagation conditions. Conventional signal processing tools such as the multidimensional sampling theorem and Fourier theory are used to build a linear system theoretic interpretation of electromagnetic wave propagations and revisit classical electromagnetic theory results, e.g., bandlimited property of an electromagnetic field, from a signal processing perspective. Scalar electromagnetic fields are considered for simplicity, which physically correspond to acoustic propagation in general or electromagnetic propagation under certain conditions. The developed approach is extended to study ensembles of a stationary random electromagnetic field that is representative of different propagation conditions.
 Publication:

arXiv eprints
 Pub Date:
 September 2021
 arXiv:
 arXiv:2109.10040
 Bibcode:
 2021arXiv210910040P
 Keywords:

 Electrical Engineering and Systems Science  Signal Processing;
 Computer Science  Information Theory;
 Physics  Optics
 EPrint:
 13 pages, 9 figures, submitted to IEEE Transactions on Signal Processing