A Unified Transmission Strategy for TDD/FDD Massive MIMO Systems With Spatial Basis Expansion Model
A Unified Transmission Strategy for TDD/FDD Massive MIMO Systems With Spatial Basis Expansion Model
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DOI：
10.1109/tvt.2016.2594706
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发表时间：
2017-04-01
影响因子：
6.8
通讯作者：
Jin, Shi
中科院分区：
文献类型：
--
作者：
Xie, Hongxiang;Gao, Feifei;Jin, Shi
针对多用户时分双工（TDD）/频分双工（FDD）大规模多输入多输出（MIMO）系统，提出了一种统一的传输策略，包括上行/下行信道估计和用户调度。借助天线阵列理论和阵列信号处理方法，建立了一种空间基展开模型（SBEM），以更少的参数维数来表示上下行信道。因此，多用户的上行和下行信道估计都可以用少量的训练资源来执行，这显著地减少了训练开销和反馈成本。同时，通过利用用户的空间信息，可以立即缓解UL训练中的导频污染问题。为了提高频谱效率，我们还设计了一个贪婪的用户调度方案在数据传输期间。与现有的低秩模型相比，新提出的SBEM提供了一种替代的信道捕获，而无需信道统计，可以应用于TDD和FDD系统。各种数值结果证实了所提出的研究。
This paper proposes a unified transmission strategy for multiuser time division duplex (TDD)/frequency division duplex (FDD) massive multiple-input-multiple-output (MIMO) systems, including uplink (UL)/downlink (DL) channel estimation and user scheduling for data transmission. With the aid of antenna array theory and array signal processing, we build a spatial basis expansion model (SBEM) to represent the UL/DL channels with far fewer parameter dimensions. Hence, both the UL and DL channel estimations of multiusers can be carried out with a small amount of training resource, which significantly reduces the training overhead and feedback cost. Meanwhile, the pilot contamination problem in the UL training is immediately relieved by exploiting the spatial information of users. To enhance the spectral efficiency, we also design a greedy user scheduling scheme during the data transmission period. Compared with existing low-rank models, the newly proposed SBEM offers an alternative for channel acquisition without the need for channel statistics and can be applied to both TDD and FDD systems. Various numerical results are provided to corroborate the proposed studies.