arXivDaily arXiv每日学术速递 周一至周五更新
arXiv 1608.01296cs.ITmath.IT
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一种基于置信传播的软多符号差分检测框架

A Belief Propagation Based Framework for Soft Multiple-Symbol Differential Detection

Chanfei Wang, Tiejun Lv, Hui Gao, Shaoshi Yang

摘要:

软非相干检测依赖于在没有信道估计的情况下计算所发送的比特的\textit{a posteriori}概率(APP),对于在高维无线通信中实现优异的检测性能是必要的。提出了一种基于置信传播(BP)的高性能软多符号差分检测(MSDD)框架(BP-MSDD),并将其应用于差分空时分组码(DSTBC)辅助的超宽带脉冲无线电(UWB-IR)系统。首先,我们重新审视的信号采样与援助的网格结构和分解的网格成多个子网格。此外,我们推导出一个APP的计算算法,其中的前向和反向的BP消息传递机制上的子网格操作。建议的BP-MSDD是能够显着优于传统的硬判决MSDD。然而,BP-MSDD的计算复杂性随着MSDD网格状态的数量呈指数增加。为了避免这种过度的复杂性,实际的实现,我们重新制定的BP-MSDD,并提出了一个基于维特比算法(VA)的硬判决MSDD(VA-HMSDD)和基于VA的软判决MSDD(VA-SMSDD)。此外,所提出的BP-MSDD和VA-SMSDD都可以与软信道解码结合使用,以获得强大的基于迭代检测和解码的接收机。仿真结果表明了所提算法在DSTBC辅助UWB-IR系统中的有效性。

英文摘要:

Soft noncoherent detection, which relies on calculating the \textit{a posteriori} probabilities (APPs) of the bits transmitted with no channel estimation, is imperative for achieving excellent detection performance in high-dimensional wireless communications. In this paper, a high-performance belief propagation (BP)-based soft multiple-symbol differential detection (MSDD) framework, dubbed BP-MSDD, is proposed with its illustrative application in differential space-time block-code (DSTBC)-aided ultra-wideband impulse radio (UWB-IR) systems. Firstly, we revisit the signal sampling with the aid of a trellis structure and decompose the trellis into multiple subtrellises. Furthermore, we derive an APP calculation algorithm, in which the forward-and-backward message passing mechanism of BP operates on the subtrellises. The proposed BP-MSDD is capable of significantly outperforming the conventional hard-decision MSDDs. However, the computational complexity of the BP-MSDD increases exponentially with the number of MSDD trellis states. To circumvent this excessive complexity for practical implementations, we reformulate the BP-MSDD, and additionally propose a Viterbi algorithm (VA)-based hard-decision MSDD (VA-HMSDD) and a VA-based soft-decision MSDD (VA-SMSDD). Moreover, both the proposed BP-MSDD and VA-SMSDD can be exploited in conjunction with soft channel decoding to obtain powerful iterative detection and decoding based receivers. Simulation results demonstrate the effectiveness of the proposed algorithms in DSTBC-aided UWB-IR systems.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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