摘要
车联网作为智能交通系统的重要组成部分,存在大量用户瞬时连接和频繁信息交换的现象。基于正交多址接入的传统网络由于访问效率低而面临拥塞问题,会导致巨大的访问延迟。非正交多址接入技术是满足下一代蜂窝通信超大连接、超低时延的关键方案之一,首先分析V2X中NOMA的适用性,给出基于正交频分复用的NOMA上行系统发送端模型;接着提出了一种基于对称扩展的联合频偏和信道估计方法;进一步提出一种基于期望值传播的低复杂度多用户检测算法;最后仿真结果表明所提算法的性能明显优于传统方法。
As an important part of the intelligent transportation system,Internet of Vehicles has a large number of user instantaneous connections and frequent information exchanges.The conventional OMA-based network faces congestion issues due to low access efficiency,resulting in significant access delay.However,NOMA has been recognized as one of the key technologies to meet the requirements of the next generation cellular networks,such as massive connection and ultra-low latency.This paper firstly analyzes the applicability of NOMA in V2X,and presents the transmitter model of the NOMA uplink system based on OFDM.Then,a joint carrier frequency offset and channel estimation method is proposed based on symmetric extension.Furthermore,a low-complexity multi-user detection algorithm is proposed based on expectation propagation(EP).Finally simulation results show that the performance of the proposed algorithm outperforms the traditional one.
作者
李华
董园园
巩彩红
张振宇
戴晓明
LI Hua;DONG Yuanyuan;GONG Caihong;ZHANG Zhenyu;DAI Xiaoming(Institute of Advanced Network Technologies and New Services Beijing Engineering and Technology Research Center for Convergence Networks and Ubiquitous Services,University of Science and Technology Beijing,Beijing 100083,China)
出处
《移动通信》
2020年第11期2-7,共6页
Mobile Communications
基金
国家自然科学基金资助项目(61871029)
北京市自然科学基金资助项目(L172049)。
关键词
车联网
非正交多址接入
信道估计
频偏
期望值传播
Internet ofVehicles
NOMA
channel estimation
carrier frequency offset
expectation propagation
