Implementation and evaluation of reactive base station selection for human blockage in mmWave communications

This paper presents implementation of a reactive base station selection scheme for millimeter-wave (mmWave) communications. In mmWave communications, the frame loss rate increases and the throughput sharply decreases when a pedestrian blocks a line-of-sight (LOS) path. To alleviate this human blockage problem, base stations can be selected so as to maintain LOS paths on the basis of communication quality. In this paper, we build a testbed using off the shelf IEEE 802.11ad based wireless local area network (WLAN) devices, and implement a reactive base station selection scheme on the testbed. To the best of our knowledge, there is no existing work which experimentally evaluates human blockage detection system using actual IEEE 802.11ad devices. Our prototype system monitors the throughput measured at each base station and detects human blockage when the throughput decreases below a threshold. The human blockage detection triggers the base station switching. Our experimental results show that the reactive base station selection scheme decreases the duration in which human blockage degrades throughput performance, and the total amount of received data increases by 21%.