Wireless sensors record physical or chemical properties in their environment. These include measured values such as temperature, humidity, pressure or pH value. The recorded data is transmitted via radio - for example, via RFID, LPWAN, Bluetooth or Wi-Fi. Active sensors generate the radio signal themselves. Passive sensors, on the other hand, have components that are activated by externally supplied energy.
Wireless sensors are used for real-time condition monitoring. Deviations from normal conditions - such as the operating temperature of a machine, the humidity in a data center or the temperature of vaccines - generate safety risks and damage. Sensors ensure permanent monitoring in real time. An immediate response to deviations can be made.
Active sensors measure the fill level of waste containers and enable predictive and intelligent collection and route planning. Soil moisture monitoring optimizes irrigation planning in smart cities. Temperature monitoring ensures the maintenance of cold chains for vaccines and food. Predictive maintenance is performed on machines in industry based on sensor data.
New, passive wireless sensors are available in the form of labels and tags - and are about the size of a postage stamp. Radio waves provide the energy for activation. Several measured values such as the fill level, humidity and temperature can be monitored by one sensor.