Hybrid approaches for device placement in Wireless Sensor Networks

Device placement is a fundamental factor in determining the coverage, and connectivity, cost and lifetime of a Wireless Sensor Network (WSN). In this project, explore the Problem of relay node placement in heterogeneous WSNs. formulate a Generalized node placement optimization problem aimed at minimizing the network Cost with constraints on lifetime and connectivity. Depending on the constraints, two representative scenarios of this problem are described. Characterize the first problem, where relay nodes are not energy constrained, as a minimum set covering problem. Further consider a more challenging scenario, where all nodes are energy limited. As an optimal solution to this problem is difficult to obtain, a two-phase approach is proposed, in which locally optimal design decisions are taken. The placement of the first phase relay nodes (FPRNs), which are directly connected to Sensor Nodes (SNs), is modeled as a minimum set covering problem. To ensure the relaying of the traffic from the FPRNs to the base station, three heuristic schemes are proposed to place the second phase relay nodes (SPRNs).

Introduction

Smart environments represent the next evolutionary development step in Building, utilities, industrial, home, shipboard, and transportation systems automation. Like any sentient organism, the smart environment relies first and fore most on sensory Data from the real world. Sensory data comes from multiple sensors of different modalities in distributed Locations. The smart environment needs information about its surroundings as well as about its internal workings; The challenges in the hierarchy of: detecting the relevant quantities, monitoring and collecting the data, assessing and evaluating the information, formulating meaningful user displays, and performing decision-making and alarm functions are enormous.