The emerging Massive Communication(MC)highlights the need for efficient short-length errorcorrection coding schemes with effective decoders.Classical Reed-Muller(RM)codes combined with the recently developed Recursive...The emerging Massive Communication(MC)highlights the need for efficient short-length errorcorrection coding schemes with effective decoders.Classical Reed-Muller(RM)codes combined with the recently developed Recursive Projection-Aggregation(RPA)decoder present a promising solution,as the RPA decoder demonstrates near Maximum Likelihood(ML)performance and supports highly parallel implementation.To address the speed and flexibility requirements of Cloud Radio Access Networks(C-RANs)across various MC applications,this paper proposes a fast and scalable RPA decoder on Graphics Processing Units(GPUs).By leveraging a thread-per-projection mapping strategy,we develop an optimized thread block architecture for the RPA decoding of second-order RM codes,which can be easily extended to construct a multi-dimensional block array for decoding higher-order RM codes.Additionally,we introduce a stationary projection pruning technique that seamlessly adapts the RPA decoder kernel to simplified variants,facilitating flexible trade-offs between error-correction performance and implementation complexity.Experimental results show that the pruned RPA decoder kernel on the NVIDIA A100 GPU achieves throughputs of 1.69 Gbps and 1.33 Gbps for the RM(6,2)and RM(7,2)codes,respectively,delivering speedups of 2.95x and 3.69x compared to a state-of-the-art software-based Successive Cancellation List(SCL)decoder.展开更多
近年来,得益于人工智能技术(Artificial Intelligence,AI)的快速发展,关于自动求解数学应用题(Math Word Problem,MWP)的研究越来越趋向成熟。在自动求解数学应用题任务中,对问题文本进行建模至关重要。针对这一问题,文章提出了一个基...近年来,得益于人工智能技术(Artificial Intelligence,AI)的快速发展,关于自动求解数学应用题(Math Word Problem,MWP)的研究越来越趋向成熟。在自动求解数学应用题任务中,对问题文本进行建模至关重要。针对这一问题,文章提出了一个基于循环神经网络(Recursive Neural Network,RNN)和Transformer编码网络的双路文本编码器(Dual Channel Text Encoder,DCTE):首先,使用循环神经网络对文本进行初步的编码;然后,利用基于自注意力(Self-attention)机制的Transformer编码网络来获得词语的远距离上下文语义信息,以增强词语和文本的语义表征。结合DCTE和GTS(Goal-Driven Tree-structured MWP Solver)解码器,得到了数学应用题求解器(DCTE-GTS模型),并在Math23k数据集上,将该模型与Graph2Tree、HMS等模型进行了对比实验;同时,为探讨编码器配置方法对模型效果的影响,进行了消融实验。对比实验结果表明:DCTE-GTS模型均优于各基准模型,答案正确率达到77.6%。消融实验结果表明双路编码器的配置方法是最优的。展开更多
双二元卷积Turbo码(DB CTC)的非二进制编码使得译码复杂度增加,限制了其在某些实际通信工程中的使用。在最大后验概率(MAP)译码算法的基础上,提出了一种优化算法,将译码的存储量和计算量降为原来的1/4。仿真结果表明:在不同编码长度和...双二元卷积Turbo码(DB CTC)的非二进制编码使得译码复杂度增加,限制了其在某些实际通信工程中的使用。在最大后验概率(MAP)译码算法的基础上,提出了一种优化算法,将译码的存储量和计算量降为原来的1/4。仿真结果表明:在不同编码长度和码率的情况下,优化算法与原算法性能相当;在误码率为10-5的条件下,两者的Eb/N0差异同样不大于0.1 d B。展开更多
This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage p...This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage probability of the scheme over Rayleigh fading channels is deduced.In an unknown channel state information(CSI) scenario,adaptive transversal filters based on a spatio-temporal recursive least squares(ST-RLS) algorithm are adopted in the destination to realize receive diversity gain.Also,a joint 'Min-Sum' iterative decoding is effectively carried out in the destination.Such a decoding algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct structured LDPC codes employed by the source and relay.Simulation results verify the effectiveness of the adopted filter in the coded cooperative MIMO scheme.Theoretical analysis and numerical simulations show that the LDPC coded cooperative MIMO scheme can well combine cooperation diversity,multi-receive diversity,and channel coding gains,and clearly outperforms coded noncooperation schemes under the same conditions.展开更多
基金supported by the Shenzhen Fundamental Research Project(No.JCYJ20220818103413029)the Shenzhen Science and Technology Program(No.GJHZ20220913144207013)the Guangdong Basic andApplied BasicR esearch Foundation(No.2023B1515120093).
摘要The emerging Massive Communication(MC)highlights the need for efficient short-length errorcorrection coding schemes with effective decoders.Classical Reed-Muller(RM)codes combined with the recently developed Recursive Projection-Aggregation(RPA)decoder present a promising solution,as the RPA decoder demonstrates near Maximum Likelihood(ML)performance and supports highly parallel implementation.To address the speed and flexibility requirements of Cloud Radio Access Networks(C-RANs)across various MC applications,this paper proposes a fast and scalable RPA decoder on Graphics Processing Units(GPUs).By leveraging a thread-per-projection mapping strategy,we develop an optimized thread block architecture for the RPA decoding of second-order RM codes,which can be easily extended to construct a multi-dimensional block array for decoding higher-order RM codes.Additionally,we introduce a stationary projection pruning technique that seamlessly adapts the RPA decoder kernel to simplified variants,facilitating flexible trade-offs between error-correction performance and implementation complexity.Experimental results show that the pruned RPA decoder kernel on the NVIDIA A100 GPU achieves throughputs of 1.69 Gbps and 1.33 Gbps for the RM(6,2)and RM(7,2)codes,respectively,delivering speedups of 2.95x and 3.69x compared to a state-of-the-art software-based Successive Cancellation List(SCL)decoder.
摘要双二元卷积Turbo码(DB CTC)的非二进制编码使得译码复杂度增加,限制了其在某些实际通信工程中的使用。在最大后验概率(MAP)译码算法的基础上,提出了一种优化算法,将译码的存储量和计算量降为原来的1/4。仿真结果表明:在不同编码长度和码率的情况下,优化算法与原算法性能相当;在误码率为10-5的条件下,两者的Eb/N0差异同样不大于0.1 d B。
基金Project (No. 20105552) supported by the Science and Technology on Avionics Integration LaboratoryNational Aeronautical Science Foundation of China
摘要This paper describes a coded cooperative multiple-input multiple-output(MIMO) scheme,where structured low-density parity-check(LDPC) codes belonging to a family of repeat-accumulate(RA) codes are employed.The outage probability of the scheme over Rayleigh fading channels is deduced.In an unknown channel state information(CSI) scenario,adaptive transversal filters based on a spatio-temporal recursive least squares(ST-RLS) algorithm are adopted in the destination to realize receive diversity gain.Also,a joint 'Min-Sum' iterative decoding is effectively carried out in the destination.Such a decoding algorithm agrees with the bilayer Tanner graph that can be used to fully characterize two distinct structured LDPC codes employed by the source and relay.Simulation results verify the effectiveness of the adopted filter in the coded cooperative MIMO scheme.Theoretical analysis and numerical simulations show that the LDPC coded cooperative MIMO scheme can well combine cooperation diversity,multi-receive diversity,and channel coding gains,and clearly outperforms coded noncooperation schemes under the same conditions.