Bounds on Space-Time-Frequency Dimensionality

Leif Hanlen; Thushara Abhayapala

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Bounds on Space-Time-Frequency Dimensionality

Leif Hanlen·Thushara Abhayapala

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Abstract

We bound the number of electromagnetic signals which may be observed over a frequency range $2W$ for a time $T$ within a region of space enclosed by a radius $R$. Our result implies that broadband fields in space cannot be arbitrarily complex: there is a finite amount of information which may be extracted from a region of space via electromagnetic radiation. Three-dimensional space allows a trade-off between large carrier frequency and bandwidth. We demonstrate applications in super-resolution and broadband communication.

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Leif Hanlen, Thushara Abhayapala. 2007-01-09. Bounds on Space-Time-Frequency Dimensionality. https://arxiv.org/abs/cs/0701055

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