Patent attributes
There is provided a building management system and a method for associating a portable sensor device with a stationary control device in such a system. Upon detection of a movement of the portable sensor device, the portable sensor device starts to transmit signals more frequently to the stationary control devices. It is determined that the movement of the portable sensor device has stopped if the signal strength of the transmitted signals received at the stationary control devices is essentially constant during a time window. In response to such a determination, the portable sensor device is associated with the stationary control device having the highest received signal strength and the portable sensor device returns to an energy-saving mode.