Positioning in ad hoc sensor networks

Position and orientation of individual nodes in ad hoc sensor networks are useful for both service and application implementation. Services that can be enabled by availability of position include routing and querying. At application level, position is required in order to label the reported data in a sensor network, whereas position and orientation enable tracking. Nodes may have local capabilities such as the possibility of measuring ranges to neighbors, angle of arrival, or global capabilities, such as GPS and digital compasses. This article surveys methods used to infer locations in a multihop fashion in networks with or without the mentioned capabilities.