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arXiv · 2208.04467

A Simple Capacity-Achieving Scheme for Channels with Polarization-Dependent Loss

Mohannad Shehadeh·Frank R. Kschischang
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Abstract

We demonstrate, for a widely used model of channels with polarization dependent loss (PDL), that channel capacity is achieved by a simple interference cancellation scheme in conjunction with a universal precoder. Crucially, the proposed scheme is not only information-theoretically optimal, but it is also exceptionally simple and concrete. It transforms the PDL channel into separate scalar additive white Gaussian noise channels, allowing off-the-shelf coding and modulation schemes designed for such channels to approach capacity. The signal-to-noise ratio (SNR) penalty incurred under 6 dB of PDL is reduced to the information-theoretic minimum of a mere 1 dB as opposed to the 4 dB SNR penalty incurred under naive over-provisioning.

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Mohannad Shehadeh, Frank R. Kschischang. 2022-08-08. A Simple Capacity-Achieving Scheme for Channels with Polarization-Dependent Loss. https://doi.org/10.1109/jlt.2022.3230266

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