An iterative detection/decoding algorithm of correlated sources for the LDPC-based relay systems is presented. The signal from the source-destination(S-D) link is formulated as a highly correlated counterpart from the...An iterative detection/decoding algorithm of correlated sources for the LDPC-based relay systems is presented. The signal from the source-destination(S-D) link is formulated as a highly correlated counterpart from the relay-destination(R-D) link. A special XOR vector is defined using the correlated hard decision information blocks from two decoders and the extrinsic information exchanged between the two decoders is derived by the log-likelihood ratio(LLR) associated with the XOR vector. Such the decoding scheme is different from the traditional turbo-like detection/decoding algorithm, where the extrinsic information is computed by the side information and the soft decoder outputs. Simulations show that the presented algorithm has a slightly better performance than the traditional turbo-like algorithm(Taking the(255,175) EG-LDPC code as an example, it achieves about 0.1 dB performance gains aroundBLER=10^(-4)). Furthermore, the presented algorithm requires fewer computing operations per iteration and has faster convergence rate. For example, the average iteration of the presented algorithm is 33 at SNR=1.8 dB, which is about twice faster than that of the turbo-like algorithm, when decoding the(961,721) QC-LDPC code. Therefore, the presented decoding algorithm of correlated sources provides an alternative decoding solution for the LDPC-based relay systems.展开更多
分析了目前分段电流舵数模转换器(DAC)在动态性能提升和芯片面积缩小等方面的局限性。提出了动态元件匹配(DEM)译码技术。设计了16 bit DAC中的DEM译码电路结构,分析了DEM译码技术的原理。对该16 bit DAC的动态性能等进行了详细仿真...分析了目前分段电流舵数模转换器(DAC)在动态性能提升和芯片面积缩小等方面的局限性。提出了动态元件匹配(DEM)译码技术。设计了16 bit DAC中的DEM译码电路结构,分析了DEM译码技术的原理。对该16 bit DAC的动态性能等进行了详细仿真,并完成了整体版图设计。该DAC核心部分芯片面积仅为2. 2 mm^2。采用0. 18μm CMOS工艺完成了该DAC的加工和性能参数测试。在1 GHz采样率和100 MHz输入信号频率条件下,该DAC的无杂散动态范围约为67 dB,三阶互调失真约为76 dB,整体性能优于目前同类研究成果。展开更多
该文利用GSM EFR(Enhanced Full Rate)语音编码参数的冗余信息,提出了一种新的基于迭代结构和参数估计的联合解码算法框架;针对GSM EFR编码参数由非等概分布和帧间相关性提供的冗余量,本文提出了联合解码算法中两类冗余信息在信道解码,...该文利用GSM EFR(Enhanced Full Rate)语音编码参数的冗余信息,提出了一种新的基于迭代结构和参数估计的联合解码算法框架;针对GSM EFR编码参数由非等概分布和帧间相关性提供的冗余量,本文提出了联合解码算法中两类冗余信息在信道解码,信源解码的分配方案。同时针对不同语音编码参数的特性,引入不同的估计准则。仿真结果表明,该文算法显著提高了GSM EFR参数接收性能,提高了解码语音信噪比,改善了接收系统性能。展开更多
基金supported by NSF of China (No.61362010,61661005)NSF of Guangxi (No.2015GXNSFAA139290,2014GXNSFBA118276,2012GXNSFAA053217)
文摘An iterative detection/decoding algorithm of correlated sources for the LDPC-based relay systems is presented. The signal from the source-destination(S-D) link is formulated as a highly correlated counterpart from the relay-destination(R-D) link. A special XOR vector is defined using the correlated hard decision information blocks from two decoders and the extrinsic information exchanged between the two decoders is derived by the log-likelihood ratio(LLR) associated with the XOR vector. Such the decoding scheme is different from the traditional turbo-like detection/decoding algorithm, where the extrinsic information is computed by the side information and the soft decoder outputs. Simulations show that the presented algorithm has a slightly better performance than the traditional turbo-like algorithm(Taking the(255,175) EG-LDPC code as an example, it achieves about 0.1 dB performance gains aroundBLER=10^(-4)). Furthermore, the presented algorithm requires fewer computing operations per iteration and has faster convergence rate. For example, the average iteration of the presented algorithm is 33 at SNR=1.8 dB, which is about twice faster than that of the turbo-like algorithm, when decoding the(961,721) QC-LDPC code. Therefore, the presented decoding algorithm of correlated sources provides an alternative decoding solution for the LDPC-based relay systems.