毫米波MIMO系统中的预编码技术研究

发布时间：2018-06-27 01:00

本文选题：毫米波 + MIMO　；参考：《南京邮电大学》2017年硕士论文

【摘要】：在第五代无线通信技术的研究中,毫米波(mmWave)通信凭借着其可利用频谱宽、抗干扰能力强、易于集成化等优势,得到了广泛的关注和研究。而将mmWave技术与目前已经广泛使用的大规模MIMO系统结合,可以在可用带宽和频谱效率上得到大幅度的提升,这是未来5G无线通信系统的一个技术方向。但与此同时,mmWave信号比目前大多数无线应用和所有蜂窝系统中使用的微波信号都要经历更大的路径损耗。大天线阵列的应用,可以很好的缓解毫米波系统难以避免的路径损耗问题,使用多个数据流的波束成形(即预编码)可以进一步改善mmWave的频谱效率。在传统的多天线系统中,预编码都是在数字域完成的。然而,mmWave系统中混合信号硬件的高成本和高功耗,迫使mmWave更加依赖于模拟处理。本文在全天线阵列的基础上,提出使用一种子天线阵列的结构来替代全天线阵列结构,并同时在数字域和模拟域上来完成整个系统的预编码。进而提出了一种基于正交匹配追踪的改进型的混合预编码算法,通过将复杂的信道容量求解问题分解为若干独立的子问题,并利用连续干扰消除的思想解决子天线阵列之间的干扰,以求得整个系统的最大信道容量问题。仿真结果表明提出的混合预编码算法在性能上十分接近最佳无约束预编码算法,且复杂度大大降低。
[Abstract]:In the research of the fifth generation wireless communication technology, millimeter wave (mmWave) communication has been widely studied because of its advantages of wide spectrum, strong anti-interference and easy integration. Combining mmWave technology with large scale MIMO systems, which has been widely used at present, can greatly improve the available bandwidth and spectral efficiency, which is a technical direction of 5G wireless communication systems in the future. At the same time, however, the current microwave signal in most wireless applications and in all cellular systems has a higher path loss. The application of large antenna array can alleviate the unavoidable path loss problem of millimeter wave system. The beamforming (i.e. precoding) of multiple data streams can further improve the spectrum efficiency of mmWave. In traditional multi-antenna systems, precoding is done in digital domain. However, the high cost and high power consumption of the mixed signal hardware in the mmWave system make it more dependent on analog processing. Based on the full antenna array, a subantenna array structure is proposed to replace the full antenna array structure, and the precoding of the whole system is completed in both digital and analog domains. Furthermore, an improved hybrid precoding algorithm based on orthogonal matching tracing is proposed, which decomposes the complex channel capacity problem into several independent sub-problems. In order to solve the problem of the maximum channel capacity of the whole system, the interference between the subantenna arrays is solved by using the idea of continuous interference cancellation. Simulation results show that the performance of the proposed hybrid precoding algorithm is very close to the optimal unconstrained precoding algorithm and the complexity is greatly reduced.
【学位授予单位】：南京邮电大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TN919.3

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