利用双天线商用WiFi信道状态信息估计到达角

商用WiFi接收模块可以提供比接收无线信号强度指示（received signal strength indication，RSSI）更细粒的信道状态信息（channel state information，CSI），利用3根天线获取CSI进行方位到达角（angle of arrival，AOA）估计已成为现实。利用正交频分复用技术（orthogonal frequency division multiplexing，OFDM）将2根天线拓展为60个虚拟天线阵，将前向平滑算法拓展到二维前向平滑算法。利用仿真的非相干信号源和相干信号源数据进行实验，结果表明，在只利用2根接收天线的前提下也能实现基于商用WiFi信号的方位角的AOA估计，所提出的2根天线的虚拟天线阵模型和二维前向平滑算法具有有效性和适用性。

AOA Estimation Based on Channel State Information Extracted from WiFi with Double Antenna

The off-the-shelf WiFi network interface card(NIC) can provide channel state information(CSI) which has more detailed information than received signal strength indication(RSSI). Using three antennas to obtain channel state information of WiFi to estimate yaw angle of arrive(AOA) has become reality. Based on orthogonal frequency division multiplexing (OFDM) technology, this paper uses two antennas instead of three antennas to create a virtual antenna array with 60 antennas instead of 90 antennas and extends the forward smoothing algorithm to the two-dimensional forward smoothing algorithm, then uses experimental data of non-coherent signal and coherent signal in view of multiple signal classification(MUSIC) to verify the algorithm proposed, which can realize yaw angle of arrive estimation just with two antennas instead of three antennas. The virtual antenna array model and two-dimensional forward smoothing algorithm with two antennas proposed in this paper have validity and applicability.