Channel state information (CSI) based Wi-Fi localization can achieve admirable decimeter-level accuracy; however, such systems require labor-intensive site survey to calibrate the AP position and the antenna array direction, which hinders practical large-scale deployment. In this article, we reveal an interesting finding that the calibration efforts for deploying the CSI localization system can be significantly reduced by simply replacing the ordinary linear antenna layout of the AP with the non-linear layout. In particular, we first present an autonomous self-calibrating method to significantly facilitate site survey for deploying CSI localization systems. Then we propose a systematical evaluation mechanism to show the fundamental reason why linear antenna layout usually leads to serious errors and why non-linear antenna layout is better off. Finally, we build a testbed with COTS devices and conduct comprehensive experiments. Results show that triangular antenna layout can achieve 80% angle of arrival (AoA) measurement error within 9° for any direction in contrast to 16° based on linear antenna layout. Moreover, we can realize promising localization accuracy as previous works even without labor-intensive site survey, where 80% localization error is within $0.60m$ .

中文翻译：

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Wi-Fi本地化支持自我校准

基于信道状态信息（CSI）的Wi-Fi本地化可以达到令人钦佩的分米级精度；然而，这样的系统需要劳动密集的现场勘测以校准AP位置和天线阵列方向，这阻碍了实际的大规模部署。在本文中，我们揭示了一个有趣的发现，即通过简单地用非线性布局替换AP的普通线性天线布局，可以显着减少部署CSI定位系统的校准工作。特别是，我们首先提出一种自主的自我校准方法，以显着促进部署CSI本地化系统的站点调查。然后，我们提出了一种系统的评估机制，以说明线性天线布局通常会导致严重错误以及非线性天线布局状况更好的根本原因。最后，我们使用COTS设备构建了一个测试平台并进行了全面的实验。结果表明，与线性天线布局的16°相比，三角形天线布局可以在9°内的任何方向上实现80％的到达角（AoA）测量误差。而且，即使没有劳动密集型的现场调查，在80％的本地化误差在 60万美元 。