Capacity Outer Bound and Degrees of Freedom of Wiener Phase Noise Channels with Oversampling

Luca Barletta; Stefano Rini

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arXiv · 1705.08148

Capacity Outer Bound and Degrees of Freedom of Wiener Phase Noise Channels with Oversampling

Luca Barletta·Stefano Rini

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Abstract

The discrete-time Wiener phase noise channel with an integrate-and-dump multi-sample receiver is studied. A novel outer bound on the capacity with an average input power constraint is derived as a function of the oversampling factor. This outer bound yields the degrees of freedom for the scenario in which the oversampling factor grows with the transmit power $P$ as $P^α$. The result shows, perhaps surprisingly, that the largest pre-log that can be attained with phase modulation at high signal-to-noise ratio is at most $1/4$.

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Luca Barletta, Stefano Rini. 2017-05-23. Capacity Outer Bound and Degrees of Freedom of Wiener Phase Noise Channels with Oversampling. https://arxiv.org/abs/1705.08148

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