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arXiv · 1103.2573

Optimization of Fast-Decodable Full-Rate STBC with Non-Vanishing Determinants

Tian Peng Ren·Yong Liang Guan·Chau Yuen·Yue Zhou·Er Yang Zhang
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Abstract

Full-rate STBC (space-time block codes) with non-vanishing determinants achieve the optimal diversity-multiplexing tradeoff but incur high decoding complexity. To permit fast decoding, Sezginer, Sari and Biglieri proposed an STBC structure with special QR decomposition characteristics. In this paper, we adopt a simplified form of this fast-decodable code structure and present a new way to optimize the code analytically. We show that the signal constellation topology (such as QAM, APSK, or PSK) has a critical impact on the existence of non-vanishing determinants of the full-rate STBC. In particular, we show for the first time that, in order for APSK-STBC to achieve non-vanishing determinant, an APSK constellation topology with constellation points lying on square grid and ring radius $\sqrt{m^2+n^2} (m,n\emph{\emph{integers}})$ needs to be used. For signal constellations with vanishing determinants, we present a methodology to analytically optimize the full-rate STBC at specific constellation dimension.

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Tian Peng Ren, Yong Liang Guan, Chau Yuen, Yue Zhou, Er Yang Zhang. 2011-03-14. Optimization of Fast-Decodable Full-Rate STBC with Non-Vanishing Determinants. https://doi.org/10.1109/tcomm.2011.050911.090148

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