Wireless sensor nodes

Wireless sensor nodes in a wireless sensor network

Wireless sensor node (radio node) in a wireless sensor networkWireless sensor nodes
(or  radio nodes) have the task to transmit the sensor data wirelessly to a wireless access point in a wireless sensor network.

Radio nodes receive the measured variables of the sensors, which are connected either by BNC connector or LEMO connector to the radio node. Exception is the TEDIASENS radio node SN-I, which receives no external sensor data, but transmits the data of its integrated industrial acceleration sensor to an access point.

But normally a SN-X sensor node receives three different input variables, which are captured simultaneously by the radio node and passed forward to the access point on the latest wireless technology. For this purpose, the wireless sensor node has a built-in wireless antenna by which the data is transferred.

WLAN sensor node

A wlan sensor node is a node in a wireless sensor network that is capable of performing some processing, gathering sensory information and communicating with other connected nodes in the network. The main components of a wlan sensor node are a microcontroller, transceiver, power source and one or more sensors.

Technical components of a sensor node

A sensor node consists of a receiving unit for receiving the sensor data, a radio unit to send the information, a processor or microcontroller to monitor the communication and a power supply. The power can be supplied either by a rechargeable battery or a power cable. The components of the radio node are surrounded by a robust, durable housing, which protects the components. By the protection, current sensor nodes are also used reliably in difficult environmental conditions.

Mounting of the sensor nodes

Sensor nodes can be installed in a wireless sensor network at any positions. Thereby, radio nodes require only little space and can be mounted at almost every place unobtrusively and compactly by screws or a magnetic attachment.

Operation of a sensor node

The sensor node receives the most analog data from the sensor. For further processing, the signals are converted by an adjustment circuit to digital data (by an A/D-converter). The controller of the radio node then processes the digital signals and prepares the data for the data transfer. In a final step, the data is transmitted via WLAN to thewireless access point.