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arXiv · 2001.10904

Optimal Augmented-Channel Puncturing for Low-Complexity Soft-Output MIMO Detectors

Mohammad M. Mansour
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Abstract

We propose a computationally-efficient soft-output detector for multiple-input multiple-output channels based on augmented channel puncturing in order to reduce tree processing complexity. The proposed detector, dubbed augmented WL detector (AWLD), employs a punctured channel with a special structure derived by triangulizing the original channel in augmented form, followed by Gaussian elimination. We prove that these punctured channels are optimal in maximizing the lower-bound on the achievable information rate (AIR) based on a newly proposed mismatched detection model. We show that the AWLD decomposes into a minimum mean-square error (MMSE) prefilter and channel-gain compensation stages, followed by a regular unaugmented WL detector (WLD). It attains the same performance as the existing AIR partial marginalization (AIR-PM) detector, but with much simpler processing.

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Mohammad M. Mansour. 2020-01-29. Optimal Augmented-Channel Puncturing for Low-Complexity Soft-Output MIMO Detectors. https://arxiv.org/abs/2001.10904

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