Wireless hardware device for detecting relations of distance, and system for monitoring relations of distance between wireless hardware devices

Described herein is a wireless device, provided with: a transceiver module, which transmits data packets that have a transmission-power level selectable from among a number of power levels and include information of the transmission-power level, and receives data packets from surrounding devices; and a control unit, which is connected to the transceiver module and controls the transmission and reception of the data packets by the transceiver module. The control unit carries out processing operations on the data packets received from the surrounding devices in a detection time interval in order to determine proximity relations between the wireless device and said surrounding devices.