Eigenfunctions of Underspread Linear Communication Systems

Sergio Barbarossa; Mikhail Tsitsvero

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arXiv · 1510.04122

Eigenfunctions of Underspread Linear Communication Systems

Sergio Barbarossa·Mikhail Tsitsvero

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Abstract

In this paper we show that the eigenfunctions can be found exactly for systems whose delay-Doppler spread function is concentrated along a straight line and they can be found in approximate sense for systems having a spread function maximally concentrated in regions of the Doppler-delay plane whose area is smaller than one. The interesting results are that: i) the instantaneous frequency of the eigenfunctions is dictated by the contour level of the time-varying transfer function; ii) the eigenvalues are restricted between the minimum and maximum value of the system time-varying transfer function, but not all values are possible, as the system exhibits an inherent quantization.

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Sergio Barbarossa, Mikhail Tsitsvero. 2015-10-14. Eigenfunctions of Underspread Linear Communication Systems. https://arxiv.org/abs/1510.04122

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