Wireless sensor network

A wireless sensor network is a collection of distributed nodes that sense physical conditions and communicate measurements over wireless links. Nodes often combine sensing, computation, and radio communication under constraints on energy, bandwidth, and reliability.

Sensor node: A device that measures physical conditions and may process or transmit data. Each node combines the sensing and communication functions that make up the network.
Wireless sensor: A sensing device that communicates its measurements over a wireless link. It is the basic measurement-producing element used in these networks.
Environmental monitoring: The systematic measurement of environmental conditions to assess changes or risks. Distributed nodes can track conditions across locations that are difficult to monitor continuously.
Wireless LAN: A local-area network that connects devices using wireless radio communication. Wireless LANs typically prioritize general-purpose connectivity over the severe power limits of sensor nodes.
Battery life: The duration a battery-powered device can operate before its energy supply is depleted. Battery replacement often dominates the cost and feasibility of long-lived sensor deployments.
Wireless ad hoc network: A wireless network whose devices communicate without relying on fixed infrastructure. Sensor nodes often form routes among themselves rather than using a central access point.
Microcontroller: A compact computer on a chip that controls hardware and runs embedded software. It processes sensor readings and coordinates radio and power-management tasks at a node.
Precision agriculture: The use of detailed, location-specific data to manage agricultural inputs and operations. Soil and crop measurements can guide irrigation, fertilization, and other field decisions.
Cellular network: A wide-area wireless communication system organized into geographic cells served by base stations. Cellular infrastructure offers broad coverage but differs from self-organizing, locally deployed sensor networks.
Network lifetime: The period during which a network continues to meet a specified operational goal. A few depleted nodes or broken routes can determine whether the deployment remains useful.

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