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arXiv · 1003.6091

Calculation of Mutual Information for Partially Coherent Gaussian Channels with Applications to Fiber Optics

Bernhard Goebel·René-Jean Essiambre·Gerhard Kramer·Peter J. Winzer·Norbert Hanik
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Abstract

The mutual information between a complex-valued channel input and its complex-valued output is decomposed into four parts based on polar coordinates: an amplitude term, a phase term, and two mixed terms. Numerical results for the additive white Gaussian noise (AWGN) channel with various inputs show that, at high signal-to-noise ratio (SNR), the amplitude and phase terms dominate the mixed terms. For the AWGN channel with a Gaussian input, analytical expressions are derived for high SNR. The decomposition method is applied to partially coherent channels and a property of such channels called "spectral loss" is developed. Spectral loss occurs in nonlinear fiber-optic channels and it may be one effect that needs to be taken into account to explain the behavior of the capacity of nonlinear fiber-optic channels presented in recent studies.

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Bernhard Goebel, René-Jean Essiambre, Gerhard Kramer, Peter J. Winzer, Norbert Hanik. 2011-04-08. Calculation of Mutual Information for Partially Coherent Gaussian Channels with Applications to Fiber Optics. https://doi.org/10.1109/tit.2011.2162187

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