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A Pragmatic Approach to Cooperative Positioning in Wireless Sensor Networks
6.1 Introduction
Location estimation in wireless sensor networks has become an important field of interest from researchers [1–3]. This is due to the demand for knowledge of the node position by the majority of applications. In environmental monitoring, such as fire or agriculture control, a basic premise to give sense to all the data measured is to know their location; if not known, data could be considered as meaningless information.
The main purpose of a localization algorithm is to estimate those positions of nodes with unknown coordinates from the following information: a priori knowledge of some node positions and intersensor measurements. Hence, the majority of existing localization methods applied in a wireless sensor network (WSN) tries to achieve the best accuracy considering the restrictions that this kind of network imposes.
Although nowadays there are many methods of localization in wireless networks, such as the global positioning system (GPS), a localization method suitable to be used in a WSN must take into account the resource constraints imposed by the nodes, such as energy consumption and the costs of transmission and computing hardware. The increase in terms of size and cost of energy required by the GPS hardware makes this ...