In this paper, we analyze the physical layer abstraction for bit interleaved coded orthogonal frequency
division multiplexing (BIC-OFDM) system from a parallel bit channel perspective. By combining the exponential
effective SNR (signal-to-noise ratio) mapping (EESM) with the maximum a posteriori (MAP) algorithm, a bit LLR
(log-likelihood ratio) wise EESM (BL-EESM) method is proposed. This method can abstract the link performance
with high accuracy, especially for the case when channel estimation is imperfect. Afterward, the BL-EESM method
is simplified by utilizing the non-linear quantization idea, which can reduce the times of exponential operation by
two orders of magnitude at wide system bandwidth, yet shows little loss in accuracy. Our proposal can be applied
to both system level simulations to save the time consumption and to practical terminals to facilitate the adaptive
modulation and coding (AMC) procedure, bringing about throughput improvement at low hardware cost.
LI Meng-shi* (李孟实), YU Hui (俞 晖), LUO Han-wen (罗汉文), XU You-yun (徐友云)
. Pragmatic Physical Layer Abstraction Method Based on Bit-LLR-Wise Exponential Effective SNR Mapping for Bit Interleaved Coded Orthogonal Frequency Division Multiplexing System[J]. Journal of Shanghai Jiaotong University(Science), 2014
, 19(2)
: 173
-180
.
DOI: 10.1007/s12204-014-1487-5
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