Wireless monitoring systems consist of sensor nodes, a base station and a data storage and control center.
nodes are small computers connected in a wireless network. These sensor
nodes are equipped with various sensors, which measure physical
characteristics. The sensor nodes are decentralized data loggers, which
also act as relay stations forwarding data from neighboring nodes to
the base station. Each sensor node independently selects a neighboring
node suitable for a fast and reliable data transmission.
communication network can be easily extended with additional sensor
nodes, which autonomously join and integrate with the existing network.
An additional advantage is the system reliability: if one of the sensor
nodes fails and, thus, is no longer available as relay station, the
affected sensor nodes independently establish new connections to
operational nodes nearby.
The base station of the wireless
communication network collects the data gathered by the sensor nodes
and establishes a connection to the data storage and control center. This connection allows for a bidirectional communication of data and
instructions between the control center and the wireless monitoring
system. The base station is connected to the Internet over a mobile
phone network (UMTS/GMS). This communication channel is encrypted which
prevents reading or changing the data by a third party.
storage and control center receives, stores and analyses the measured
data. Automatic analysis methods permit to detect unusual and undesired
trends at an early stage and thus to take appropriate measures (e.g.
alarming the responsible people). Sensor node configuration and remote
maintenance of the network is performed from the control center.
modular architecture of the system allows for easy adoption to a wide
range of application requirements and makes it suitable for a variety
of measurement tasks.