论文标题
在多 - 安德滕纳系统中欺骗攻击下的通道估计器的设计和性能分析
Design and performance analysis of channel estimators under pilot spoofing attacks in multiple-antenna systems
论文作者
论文摘要
在多个天线系统中，在频道互惠的假设下，在基本站（BS）中使用空间预编码器设计通过上行链路飞行器传输获取的通道状态信息。恶意窃听者可以开始进行欺骗攻击以改变这种设计，以改善其在下行链路中的窃听性能。本文的目的是通过假设BS知道合法通道的到达角度（AOA）来研究飞行员欺骗攻击对上行链路通道估计的影响。具体而言，在评估了简单最小二乘估计器（LSE）的性能之后，我们考虑了更复杂的估计量，例如最大似然估计器（MLE）和最小均方根误差估计器（MMSEE）的不同版本，涉及有关飞行员Spofing攻击的先验信息的不同程度。理论分析和数值模拟用于比较此类估计器的性能。特别是，我们在分析上证明，在涉及合法和欺骗通道的AOA的某些条件下，可以完全抑制高信噪比机制中的欺骗效应。此外，我们表明，即使是对AOA的不完善的知识以及欺骗信号的平均传输功率，也可以使MLE和MMSEE在LSE上实现显着的性能提高。
In multiple antenna systems employing time-division duplexing, spatial precoder design at the base station (BS) leverages channel state information acquired through uplink pilot transmission, under the assumption of channel reciprocity. Malicious eavesdroppers can start pilot spoofing attacks to alter such design, so as to improve their eavesdropping performance in downlink. The aim of this paper is to study the effects of pilot spoofing attacks on uplink channel estimation, by assuming that the BS knows the angle of arrivals (AoAs) of the legitimate channels. Specifically, after assessing the performance of the simple least squares estimator (LSE), we consider more sophisticated estimators, such as the maximum likelihood estimator (MLE) and different versions of the minimum mean square error estimator (MMSEE), involving different degrees of a priori information about the pilot spoofing attacks. Theoretical analysis and numerical simulations are used to compare the performance of such estimators. In particular, we analytically demonstrate that the spoofing effects in the high signal-to-noise regime can be completely suppressed, under certain conditions involving the AoAs of the legitimate and spoofing channels. Moreover, we show that even an imperfect knowledge of the AoAs and of the average transmission power of the spoofing signals allows the MLE and MMSEE to achieve significant performance gains over the LSE.
