额外信息可靠传输新技术——便车码的构造与应用  

A New Technology for Reliable Transmission of Extra Data——Free-ride Codes with Constructions and Applications

作　　者：王千帆[1] 蔡穗华 颉满刚 王寅楚 于晓璞 马啸[1] WANG Qianfan;CAI Suihua;XIE Mangang;WANG Yinchu;YU Xiaopu;MA Xiao(School of Computer Science and Engineering,Sun Yat-sen University,Guangzhou 510006,China;School of Electronics and Information Technology,Sun Yat-sen University,Guangzhou 510006,China;Wireless Network RAN Research Department,Shanghai Huawei Technologies Co.,Ltd.,Shanghai 201206,China)

机构地区：[1]中山大学计算机学院,广东广州510006 [2]中山大学电子与信息工程学院,广东广州510006 [3]上海华为技术有限公司无线网络RAN研究部,上海201206

出　　处：《无线电通信技术》2022年第5期812-821,共10页Radio Communications Technology

摘　　要：在实际通信中,除了需要编码传输应用所需负载数据外,往往还需要传输由于通信协议、网络控制等产生的少量标签或控制信令等额外信息。传统的方法是将以上两类数据分别进行编码传输,其中数据信道常用的编码方案为低密度校验(Low-density Parity-check,LDPC)码。介绍了面向LDPC码的额外信息便车传输技术,其可以基于现有的LDPC码传输链路,将额外信息嵌入负载数据码字中进行传输,从而避免了额外的传输资源消耗。需要特别指出的是,采用便车码传输的额外信息相对于负载链路具有更高的可靠性,且其对原始负载链路的性能几无影响。在理论分析方面,从信息论角度提出了伴随式信道及其容量的概念,从而阐明了基于便车码传输额外信息的可行性;在实际构造方面,给出了随机构造和结构化构造等两类便车码,并对负载链路在有额外信息传输情况下的误码字率和误比特率进行了性能分析与展示。基于便车码的良好特性,分别将其应用于耦合码构造、反馈信息传输以及车联网中关键通信场景设计等方面;最后指出关于便车码的研究方兴未艾,并阐述了未来便车码在其编码构造、译码设计及应用拓展等方面可能的研究方向。For practical communication,in addition to payload data transmitted over data channel for applications,extra data is usually required to be transmitted for communication protocols or network controls.These two types of data are usually separately encoded and transmitted,where Low-density Parity-check(LDPC)codes can be implemented as Error-Correction Codes(ECCs)for the data channel.In this paper,we review the free-ride coding,which is based on the conventional LDPC codes.By using the free-ride coding,a few extra bits can be transmitted over an LDPC coded link in a superposition manner but without any cost of extra transmission energy or extra bandwidth.Particularly,the extra transmission using the free-ride coding is usually more reliable than the payload transmission and has a negligible effect on the original payload transmission.From the information theory perspective,the syndrome channel and its accessible capacity is presented,implying that transmitting extra bits over the syndrome channel is feasible.For practical designs of the free-ride codes,the random construction and the structured construction are presented,where the Word Error Rate(WER)and Bit Error Rate(BER)performances of the payload data with free-ride transmission is analyzed and simulated.The free-ride codes have been applied to constructions of coupling codes,feedback transmission,and transmission design for Internet of Vehicles.Generally speaking,the free-ride coding is just unfolding and hence there are more further researches in encoding constructions,decoding designs and applications of the free-ride codes.

关 键 词：额外信息传输 便车码 低密度校验码 接入容量 

分 类 号：TN919.23[电子电信—通信与信息系统]