Density Criteria for the Identification of Linear Time-Varying Systems

Céline Aubel; Helmut Bölcskei

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arXiv · 1504.05036

Density Criteria for the Identification of Linear Time-Varying Systems

Céline Aubel·Helmut Bölcskei

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Abstract

This paper addresses the problem of identifying a linear time-varying (LTV) system characterized by a (possibly infinite) discrete set of delays and Doppler shifts. We prove that stable identifiability is possible if the upper uniform Beurling density of the delay-Doppler support set is strictly smaller than 1/2 and stable identifiability is impossible for densities strictly larger than 1/2. The proof of this density theorem reveals an interesting relation between LTV system identification and interpolation in the Bargmann-Fock space. Finally, we introduce a subspace method for solving the system identification problem at hand.

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BibTeX RIS

Céline Aubel, Helmut Bölcskei. 2015-04-20. Density Criteria for the Identification of Linear Time-Varying Systems. https://arxiv.org/abs/1504.05036

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