Barrier coverage in visual camera sensor networks (visual barrier coverage) has important real-world applications like battlefield surveillance, environmental monitoring, and protection of government property. Cost-effective deployment, a fundamental issue of visual barrier coverage, considers how to deploy the fewest camera sensors along the barrier to detect intruders (e.g., capture faces) with desirable performance. Existing visual barrier coverage approaches like full-view coverage require numerous camera sensors for capturing intruders' faces deterministically for any trajectory and facing angle. However, intruders' trajectories and facing angles are bounded and deterministic intruder detection requires many camera sensors for rare intrusion cases. Certain practical applications can tolerate limited intrusion mis-detection given budget limitations. This paper proposes local face-view barrier coverage, a novel concept that achieves statistical barrier coverage in camera sensor networks leveraging intruders' trajectory lengths ℓ along the barrier and head rotation angles δ. Using (ℓ, δ) and other parameters, we derive a rigorous probability bound for intruder detection for local face-view barrier coverage via a feasible deployment pattern. Our detection probability bound and deployment pattern can guide practical camera sensor network deployments with camera sensor budgets. Extensive evaluations show that local face-view barrier coverage requires up to 50% fewer camera sensors than full-view barrier coverage.

In this article, we address a new unexplored problem: what are the optimal patterns to achieve connected coverage in wireless networks with directional antennas. As their name implies, directional antennas can focus their transmission energy in a certain direction. This feature leads to lower cross-interference and larger communication distance. It has been shown that, with proper scheduling mechanisms, directional antennas may substantially improve networking performance in wireless networks. In this article, we propose a set of deployment patterns to achieve full coverage and up to 2-connectivity under two different antenna models, namely the sector model and the knob model. These patterns are optimal under most combinations of communication and sensing ranges. We also introduce with detailed analysis several fundamental theorems and conjectures. Finally, we examine a more realistic physical model, where there might be strong interference and both the sensing range and the communication range might be irregular. The results show that our designed patterns work well even in unstable and fickle physical environments.

In this paper, we study the problem of wireless coverage in bounded areas. Coverage is one of the fundamental requirements of wireless networks. There has been considerable research on optimal coverage of infinitely large areas. However, in the real world, the deployment areas of wireless networks are always geographically bounded. It is a much more challenging and significant problem to find optimal deployment patterns to cover bounded areas. In this paper, we approach this problem starting from the development of tight lower bounds on the number of nodes needed to cover a bounded area. Then we design several deployment patterns for different kinds of convex and concave shapes such as rectangles and L-shapes. These patterns require only few more nodes than the theoretical lower bound, and can achieve efficient coverage. We have also carefully addressed and evaluated practical conditions such as coverage modeling and connectivity regarding our deployment patterns.

In this paper, we address a new unexplored problem - what are the optimal patterns to achieve connected coverage in wireless networks with directional antennas. As their name implies, directional antennas can focus their transmission energy in a certain direction. This feature leads to lower cross-interference and larger communication distance. It has been shown that with proper scheduling mechanisms, directional antennas may substantially improve networking performance in wireless networks. In this paper, we propose a set of optimal patterns to achieve full coverage and global connectivity under two different antenna models, i.e., the sector model and the knob model. We also introduce with detailed analysis several fundamental theorems and conjectures. Finally, we examine a more realistic physical model, where there might be strong interference, and both the sensing range and the communication range might be irregular. The results show that our designed patterns work well even in unstable and fickle physical environments.