Leveraging TPDV to Direction Estimation With a Single Pair of Commodity Devices

In this paper, we propose an indoor passive human tracking system equipped with only one pair of commodity Wi-Fi devices, namely WiBlinker. The key insight is that the motion of moving target not only introduce Doppler frequency shift, but also changes the value of phase difference between two adjacent antennas of the receiver. First of all, a light-weight interpolation scheme is presented to remove the random phase noise in channel state information for improving the accuracy of the trajectory tracing. Instead of using AoA to obtain the moving direction, WiBlinker employs the trend of phase difference variation in direction estimation which is no need multiple Wi-Fi devices and easier to be achieved. Experimental results show that WiBlinker outperforms the conventional multiple Wi-Fi links methods, especially in the case of a sharp turn.