  Stringent line-of-sight demands necessitated by the fast attenuating nature
of millimeter waves (mmWaves) through obstacles pose one of the central
problems of next generation wireless networks. These mmWave links are easily
disrupted due to obstacles, including vehicles and pedestrians, which cause
degradation in link quality and even link failure. Dynamic obstacles are
usually tracked by dedicated tracking hardware like RGB-D cameras, which
usually have small ranges, and hence lead to prohibitively increased deployment
costs to achieve complete coverage of the deployment area. In this manuscript,
we propose an altogether different approach to track multiple dynamic obstacles
in an mmWave network, solely based on short-term historical link failure
information, without resorting to any dedicated tracking hardware. After
proving that the said problem is NP-complete, we employ a greedy set-cover
based approach to solve it. Using the obtained trajectories, we perform
proactive handoffs for at-risk links. We compare our approach with an RGB-D
camera-based approach and show that our approach provides better tracking and
handoff performances when the camera coverage is low to moderate, which is
often the case in real deployment scenarios.
