关键词：无线传感器网络；三维网络；3D；靶向度
摘 要：A wireless sensor network (WSN) is categorized as three-dimensional (3D) when variation in the height of deployed sensor nodes is not negligible as compared to length and breadth of deployment field. The fundamental problem in such 3D networks is to find an optimal way to deploy sensor nodes needed to maintain full (or targeted degree of) coverage of monitored volume and reliable connectivity as desired by network designers. The solution should yield lower bound on number of nodes needed to achieve full coverage and connectivity. However, optimizing coverage and connectivity in 3D WSNs comes with its inherent complexities and intrinsic design challenges. 3D WSNs are not only difficult to visualize but their analysis is also computationally intensive. This literature summarizes major work conducted in the domain of coverage and connectivity in 3D WSNs. It studies different placement strategies, fundamental characteristics, modeling schemes, analytical methods, limiting factors, and practical constraints dealing with coverage and connectivity in 3D WSNs.