在时分双工大规模多输入多输出（multiple-input multiple-output，MIMO）系统中，上下行通道的互易性校准是非常关键的。在相对校准方案中，系统仅需获得天线之间的信道响应，无需增加额外的硬件电路，其中最小二乘（least square，LS）校准表现出了较高的精度。然而，LS校准导致算法复杂度过高。该文提出了一种局部校准方案，利用若干组局部天线间的通道测量，使校准精确度得到保证，并且通过限制局部天线的规模降低校准复杂度。仿真结果表明：该方案可在大幅度降低计算复杂度的前提下保证校准精度损失很小。
Abstract
Reciprocity calibrations between the uplink and downlink channels are very important in time division duplex (TDD) massive multiple-input multiple-output (MIMO) systems. When the calibration has no additional radio frequency (RF) chain, the calibration was sounding between different antenna elements. The least squares (LS) method is then used to analyze the data, but the analysis is very complex. This paper describes a calibration method based on a local calibration. The method is accurate since the local calibration only uses results between nearby antennas and simpler due to limited size of each local calibration. Simulations show that the complexity is reduced without significant accuracy loss.
关键词
大规模多输入多输出(MIMO) /
互易性校准 /
最小二乘(LS)校准 /
局部校准
Key words
massive multiple-input multiple-output (MIMO) /
reciprocity calibration /
least square calibration /
local calibration
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参考文献
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