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arXiv · 2504.11448

Full-Diversity Construction-D Lattices: Design and Decoding Perspective on Block-Fading Channels

Maryam Sadeghi·Hassan Khodaiemehr·Chen Feng
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Abstract

This paper introduces a novel framework for constructing algebraic lattices based on Construction-D, leveraging nested linear codes and prime ideals from algebraic number fields. We focus on the application of these lattices in block-fading (BF) channels, which are characterized by piecewise-constant fading across blocks of transmitted symbols. This approach results in a semi-systematic generator matrix, providing a structured foundation for high-dimensional lattice design for BF channels. The proposed Construction-D lattices exhibit the full diversity property, making them highly effective for error performance improvement. To address this, we develop an efficient decoding algorithm designed specifically for full-diversity Construction-D lattices. Simulations indicate that the proposed lattices notably enhance error performance compared to full-diversity Construction-A lattices in diversity-2 cases. Interestingly, unlike AWGN channels, the expected performance enhancement of Construction-D over Construction-A, resulting from an increased number of nested code levels, was observed only in the two-level and diversity-2 cases. This phenomenon is likely attributed to the intensified effects of error propagation that occur during successive cancellation at higher levels, as well as the higher diversity orders. These findings highlight the promise of Construction-D lattices as an effective coding strategy for enhancing communication reliability in BF channels.

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Maryam Sadeghi, Hassan Khodaiemehr, Chen Feng. 2025-04-15. Full-Diversity Construction-D Lattices: Design and Decoding Perspective on Block-Fading Channels. https://arxiv.org/abs/2504.11448

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