Connected wireless camera network deployment with visibility coverage

System deployments of IoT systems have drawn research attention, because it is very challenging to meet both physical and cyber constraints in real systems. In this article, we consider the problem of deploying wireless camera networks inside a complex indoor setting for surveillance applications. We formulate the problem of the minimum connected guarding network whose objective is to place a minimum number of cameras satisfying both visual coverage of the domain and wireless network connectivity. We prove that finding the minimum connected guarding network is NP-hard in both the geometric and discrete settings. We also give a 2-approximation algorithm to the geometric minimum guarding network problem. Motivated by the connection of this problem with the watchman tour problem and the art gallery problem, we developed two algorithms to calculate the locations of camera deployment. By deploying a prototype testbed, we verify the feasibility of the system design. Using simulations on 20 real floor plans, we demonstrate that our solutions reduce the number of cameras by up to 28%, and reduce the number of relay nodes by up to 47%.