5G多用户非正交共享接入中干扰消除技术研究

发布时间：2018-01-22 15:35

  本文关键词： 非正交多址接入 多用户检测 信道容量 串行干扰消除 最小均方误差　出处：《哈尔滨工业大学》2016年硕士论文　论文类型：学位论文

【摘要】：随着移动通信的发展,4G已大规模商用,面向2020年的5G技术研究如火如荼。物联网时代的到来,使得5G将会面临海量连接的场景,迫切需要进一步提升系统容量。现有的正交多址接入技术无法满足5G多场景需求,非正交多址接入技术在信道容量性能上的优越性使得非正交多址接入技术成为5G中的热门候选技术。本文首先介绍了四种多用户非正交接入系统以及多用户检测技术。非正交系统在发送端引入非正交,和正交多址接入不同,用户数据互相不正交使得用户之间存在较大干扰,所以接收端要利用复杂的多用户检测技术来分离用户数据。线性检测技术实现简单,但是难以满足系统性能需求,因此在接收端采用线性检测模块和串行干扰消除接收机相结合的接收机算法。其次,本文研究了下行多用户非正交共享接入模型。以下行两用户非正交模型为基础,通过对下行AWGN信道容量的分析,论证了非正交接入方式的优越性。对下行干扰消除方案进行分析,并给出仿真结果验证其误码性能。并进一步对下行多用户非正交共享接入模型进行改进,在发送端叠加编码后引入扩展序列,进一步提升系统的误码性能。最后,本文研究了上行多用户非正交接入模型。通过研究上行链路AWGN信道下的信道容量,证明了非正交多址上行信道容量优于正交多址接入。对上行多用户接入模型发送端进行研究,对比分析了采用不同扩展序列的性能,仿真结果表明采用复数多元序列性能更优。在接收端,深入研究了MMSE-SIC算法,通过仿真给出用户过载和误码性能曲线。针对MMSE-SIC时延较大的问题,本文提出了准并行干扰消除算法,该算法减小了时延,但是过载性能有所下降。于是在此基础上提出改进干扰消除方案,保证过载性能的情况下,减小了高负载场景下系统时延。
[Abstract]:With the development of mobile communication, 4G has been used on a large scale. In 2020, the 5G technology research is in full swing. With the coming of Internet of things, 5G will face the scene of massive connection. There is an urgent need to further enhance the system capacity. The existing orthogonal multiple access technology can not meet the 5G multi-scene requirements. The superiority of non-orthogonal multiple access technology in channel capacity performance makes non-orthogonal multiple access technology a hot candidate in 5G. This paper first introduces four kinds of multi-user non-orthogonal access systems and multi-user detection. Measurement techniques. Non-orthogonal systems are introduced at the transmitter. Different from orthogonal multiple access, user data is not orthogonal to each other, so the receiver should use complex multi-user detection technology to separate user data. Linear detection technology is simple. However, it is difficult to meet the performance requirements of the system, so the receiver algorithm combining linear detection module and serial interference cancellation receiver is adopted in the receiver. Secondly. This paper studies the downlink multi-user non-orthogonal shared access model. Based on the following two-user non-orthogonal model, the channel capacity of downlink AWGN is analyzed. The superiority of non-orthogonal access is demonstrated. The scheme of downlink interference cancellation is analyzed, and the simulation results are given to verify its error performance. Furthermore, the multi-user non-orthogonal shared access model is further improved. After superposition coding at the transmitter, the extended sequence is introduced to further improve the error performance of the system. Finally. This paper studies the uplink multi-user non-orthogonal access model and the channel capacity under uplink AWGN channel. It is proved that the capacity of non-orthogonal multiple access uplink is better than that of orthogonal multiple access. Simulation results show that the performance of complex multivariate sequences is better. At the receiving end, the MMSE-SIC algorithm is deeply studied. The user overload and error performance curves are given by simulation. In order to solve the problem of large delay in MMSE-SIC, a quasi-parallel interference cancellation algorithm is proposed, which reduces the delay. On the basis of this, an improved interference cancellation scheme is proposed to ensure the overload performance and reduce the system delay in the high-load scenario.
【学位授予单位】：哈尔滨工业大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TN929.5
，

本文编号：1455062