Connectivity-guaranteed and obstacle-adaptive deployment schemes for mobile sensor networks

Mobile sensors can relocate and self-deploy into a network. While focusing on the problems of coverage, existing deployment schemes largely over-simplify the conditions for network connectivity: they either assume that the communication range is large enough for sensors in geometric neighborhoods to obtain location information through local communication, or they assume a dense network that remains connected. In addition, an obstacle-free field or full knowledge of the field layout is often assumed. We present new schemes that are not governed by these assumptions, and thus adapt to a wider range of application scenarios. The schemes are designed to maximize sensing coverage and also guarantee connectivity for a network with arbitrary sensor communication/sensing ranges or node densities, at the cost of a small moving distance. The schemes do not need any knowledge of the field layout, which can be irregular and have obstacles/holes of arbitrary shape. Our first scheme is an enhanced form of the traditional virtual-force-based method, which we term the Connectivity-Preserved Virtual Force (CPVF) scheme. We show that the localized communication, which is the very reason for its simplicity, results in poor coverage in certain cases. We then describe a Floor-based scheme which overcomes the difficulties of CPVF and, as a result, significantly outperforms it and other state-of-the-art approaches. Throughout the paper our conclusions are corroborated by the results from extensive simulations

Resilient Wireless Sensor Networks Using Topology Control: A Review

Wireless sensor networks (WSNs) may be deployed in failure-prone environments, and WSNs nodes easily fail due to unreliable wireless connections, malicious attacks and resource-constrained features. Nevertheless, if WSNs can tolerate at most losing k − 1 nodes while the rest of nodes remain connected, the network is called k − connected. k is one of the most important indicators for WSNs’ self-healing capability. Following a WSN design flow, this paper surveys resilience issues from the topology control and multi-path routing point of view. This paper provides a discussion on transmission and failure models, which have an important impact on research results. Afterwards, this paper reviews theoretical results and representative topology control approaches to guarantee WSNs to be k − connected at three different network deployment stages: pre-deployment, post-deployment and re-deployment. Multi-path routing protocols are discussed, and many NP-complete or NP-hard problems regarding topology control are identified. The challenging open issues are discussed at the end. This paper can serve as a guideline to design resilient WSNs

Obstacle-Resistant Deployment Algorithms for Wireless Sensor Networks

[[abstract]]Node deployment is an important issue in wireless sensor networks (WSNs). Sensor nodes should be efficiently deployed in a predetermined region in a low-cost and high-coverage-quality manner. Random deployment is the simplest way to deploy sensor nodes but may cause unbalanced deployment and, therefore, increase hardware costs and create coverage holes. This paper presents the efficient obstacle-resistant robot deployment (ORRD) algorithm, which involves the design of a node placement policy, a serpentine movement policy, obstacle-handling rules, and boundary rules. By applying the proposed ORRD, the robot rapidly deploys a near-minimal number of sensor nodes to achieve full sensing coverage, even though there exist unpredicted obstacles with regular or irregular shapes. Performance results reveal that ORRD outperforms the existing robot deployment mechanism in terms of power conservation and obstacle resistance and, therefore, achieves better deployment performance.[[incitationindex]]SC

Coverage Protocols for Wireless Sensor Networks: Review and Future Directions

The coverage problem in wireless sensor networks (WSNs) can be generally defined as a measure of how effectively a network field is monitored by its sensor nodes. This problem has attracted a lot of interest over the years and as a result, many coverage protocols were proposed. In this survey, we first propose a taxonomy for classifying coverage protocols in WSNs. Then, we classify the coverage protocols into three categories (i.e. coverage aware deployment protocols, sleep scheduling protocols for flat networks, and cluster-based sleep scheduling protocols) based on the network stage where the coverage is optimized. For each category, relevant protocols are thoroughly reviewed and classified based on the adopted coverage techniques. Finally, we discuss open issues (and recommend future directions to resolve them) associated with the design of realistic coverage protocols. Issues such as realistic sensing models, realistic energy consumption models, realistic connectivity models and sensor localization are covered

Simulasi Coverage Wireless Sensor Network dengan Sum of Weighted Cost Function Genetic Algorithm

Masalah coverage pada wireless sensor network (WSN) adalah untuk meletakan sensor pada service area yang dapat mencakup seluruh service area. Masalah coverage dalam WSN sangat penting karena merepresentasikan QoS (Quality of Service) dari WSN tersebut. Pada paper ini akan disajikan sebuah simulasi untuk merancang sebuah system dengan coverage area yang optimal dengan sebuah algorithma genetika yang dikombinasikan dengan sum of weighted cost functions untuk penentuan komposisi berbagai macam letak dan jenis sensor yang dapat mengkover area seluas-luasnya dan dengan biaya seminimal mungkin. Dengan sum of weighted cost functions, perbandingan kedua fungsi dapat diatur, sehingga didapatkan optimisasi pada kedua fungsi tersebut. Fungsi-fungsi dalam hal ini adalah fungsi cost function yang merepresentasikan biaya total WSN dan fitness function yang merepresentasikan coverage sensor nodes

Analisa Kinerja dan Simulasi Coverage Wireless Sensor Network dengan Sum of Weighted Cost Function Genetic Algorithm

Masalah coverage pada wireless sensor network (WSN) adalah untuk meletakan sensor pada service area yang dapat mencakup seluruh service area. Masalah coverage dalam WSN sangat penting karena merepresentasikan QoS (Quality of Service) dari WSN tersebut. Pada paper ini akan disajikan sebuah simulasi untuk merancang sebuah system dengan coverage area yang optimal dengan sebuah algorithma genetika yang dikombinasikan dengan sum of weighted cost functions untuk penentuan komposisi berbagai macam letak dan jenis sensor yang dapat mengkover area seluas-luasnya dan dengan biaya seminimal mungkin. Dengan sum of weighted cost functions, perbandingan kedua fungsi dapat diatur, sehingga didapatkan optimisasi pada kedua fungsi tersebut. Fungsi-fungsi dalam hal ini adalah fungsi cost function yang merepresentasikan biaya total WSN dan fitness function yang merepresentasikan coverage sensor nodes

An Energy-Efficient Distributed Algorithm for k-Coverage Problem in Wireless Sensor Networks

Wireless sensor networks (WSNs) have recently achieved a great deal of attention due to its numerous attractive applications in many different fields. Sensors and WSNs possesses a number of special characteristics that make them very promising in many applications, but also put on them lots of constraints that make issues in sensor network particularly difficult. These issues may include topology control, routing, coverage, security, and data management. In this thesis, we focus our attention on the coverage problem. Firstly, we define the Sensor Energy-efficient Scheduling for k-coverage (SESK) problem. We then solve it by proposing a novel, completely localized and distributed scheduling approach, naming Distributed Energy-efficient Scheduling for k-coverage (DESK) such that the energy consumption among all the sensors is balanced, and the network lifetime is maximized while still satisfying the k-coverage requirement. Finally, in related work section we conduct an extensive survey of the existing work in literature that focuses on with the coverage problem

Coverage and Connectivity Improvement Algorithms for the Wireless Sensor Networks

In this paper we study the increase of coverage and connectivity in a sensor network with a view to improving coverage, while preserving the network’s coverage. We also examine the impact of on the related problem of coverage-boundary detection. We reduce both problems to the computation of Voronoi diagrams and intersectional point method prove and achieve lower bounds on the solution of these problems and present efficient distributed algorithms for computing and maintaining solutions in cases of sensor failures or insertion of new sensors. We prove the correctness and termination properties of our distributed algorithms, and analytically characterize the time complexity and the traffic generated by our algorithms. Our algorithms show that the increase coverage & Connectivity in wireless sensor density