Explicit and almost sure conditions for K/2 degrees of freedom

David Stotz; Helmut Bölcskei

doi:10.1109/isit.2014.6874877

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arXiv · 1404.7374

Explicit and almost sure conditions for K/2 degrees of freedom

David Stotz·Helmut Bölcskei

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Abstract

It is well known that in K-user constant single-antenna interference channels K/2 degrees of freedom (DoF) can be achieved for almost all channel matrices. Explicit conditions on the channel matrix to admit K/2 DoF are, however, not available. The purpose of this paper is to identify such explicit conditions, which are satisfied for almost all channel matrices. We also provide a construction of corresponding asymptotically DoF-optimal input distributions. The main technical tool used is a recent breakthrough result by Hochman in fractal geometry.

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David Stotz, Helmut Bölcskei. 2014-04-29. Explicit and almost sure conditions for K/2 degrees of freedom. https://doi.org/10.1109/isit.2014.6874877

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