Abstract:
With the increasing amount of mobile data and the demand for high data rates, current 2.4GHz/5GHz wireless local area networks (WLANs) are facing the problem of limited capacity. Millimeter-wave (mmWave) networks with gigahertz of channel bandwidth can provide multi-gigabit per second data rates, making it possible to support novel applications such as augmented/virtual reality (AR/VR), mobile offloading, high-resolution video streaming, etc. However, despite the potential, the directional nature of mmWave WLAN makes it prone to blockages and mobility. The dense deployment of Access Points (APs) brings unpredictable interference and non-negligible beamforming overhead. Moreover, current mmWave WLANs are application agnostic, resulting in inefficient usage of resources in supporting AR/VR type bandwidth-intensive applications. In this dissertation, I propose novel solutions to four key challenges, aiming to build practical, reliable, and efficient mmWave WLANs. Firstly, I explore a proactive blockage mitigation technique that utilizes joint transmissions of multiple APs to provide blockage resilience. Secondly, I characterize interference in dense mmWave WLANs and implement three interference mitigation techniques using commercial-off-the-shelf (COTS) devices. Thirdly, focusing on reducing the beamforming overhead, I propose a “Networked beamforming” model to reduce the number of APs that conduct beamforming in dense mmWave WLANs, resulting in significant improvements in network throughput. Lastly, I design novel solutions for blockage prediction and prefetching based on users’ six-degree-of-freedom (6DoF) position and orientation information to facilitate high-quality volumetric video streaming over mmWave WLANs.
