Augmenting Transmission Environments for Better Communications: Tunable Reflector Assisted MmWave WLANs

Conventional design of wireless transmissions mainly focuses on manipulating end devices to better adapt to the transmission environments, such as channel coding and modulation techniques, whose performance is significantly affected by the quality of the transmission environments. In this paper, we propose an innovative idea to proactively manipulate, reconfigure, and augment wireless transmission environments to better support end-to-end services. Specifically, we implement this idea into the commercialized millimeter-wave (mmWave) wireless local area networks (WLANs) to address the vulnerability to blockages in mmWave bands. Without damaging the aesthetic nature of environments, we deploy multiple small-piece highly-reflective metallic reflecting surfaces as tunable reflectors, where alternative indirect line-of-sight links are created by tuning the orientations of the reflecting surfaces. To demonstrate our idea, we devise a novel adaptive mechanism, mmRef, to enable the implementation of tunable reflectors in mmWave WLANs, where the system architecture, operational procedures, and the signaling process are developed, respectively. To theoretically quantify the expected benefits, we characterize the outage probability and system throughput of mmRef mechanism based on stochastic geometry theory. Simulation and numerical results demonstrate the effectiveness of implementing mmRef and the significantly improved system performance.