Asymptotic coded BER analysis for MIMO BICM-ID with quantized extrinsic LLR

I. Wei Lai*, Chien Yi Wang, Tzi Dar Chiueh, Gerd Ascheid, Heinrich Meyr


研究成果: 雜誌貢獻期刊論文同行評審

2 引文 斯高帕斯(Scopus)


In this paper, we derive a closed-form expression for the probability density/mass function (PDF/PMF) and the moment generating function (MGF) of the quantized detector soft output, i.e., extrinsic log-likelihood ratio (LLR), for multiple-input multiple-output (MIMO) bit-interleaved coded modulation with iterative decoding (BICM-ID) systems. The effect of either LLR clipping or LLR clipping with rounding, often applied in practical implementations, are considered. Using the derived expression, we analyze the asymptotic coded bit error rate (BER) for MIMO BICM-ID systems with the two quantization operations under a flat Rayleigh fading channel. The error rate degradation caused by quantizing the extrinsic LLR is then interpreted as an additional signal-to-noise ratio (SNR) loss. Rather than Monte Carlo simulations, this theoretical treatment provides a more convenient alternative to determining the clipping level and optimal word-length (the number of bits needed to represent signals) for LLR in a BICM-ID implementation. Finally, several other applications of this proposed theoretical analysis are also demonstrated.

頁(從 - 到)2820-2828
期刊IEEE Transactions on Communications
出版狀態已發佈 - 2012

ASJC Scopus subject areas

  • 電氣與電子工程


深入研究「Asymptotic coded BER analysis for MIMO BICM-ID with quantized extrinsic LLR」主題。共同形成了獨特的指紋。