With reference to FIG. 2, the sensor(s) 125, 220 may notice at least one wireless signal from at least one personal electronic device 205; the signal may comprise strength 210 and directionality 215. The signal may comprise a known wireless signal that the sensor 220 or the controller 110 may be able to associate with a specific person, people, or entity (such as a musical instrument, explosives, water pipes, or anything that may have preferred state values) that is associated with the personal electronic device 205. A specific wireless signal may be associated with a specific entity through it having previously connected to an existing network, through its bluetooth address, through its MAC address which it broadcasts occasionally, even when the wireless network is turned off on the phone, through being stored in a database associated with the controller 110, or through another method. The sensor 125, 220 may infer from the existence of the personal electronic device 205 that there is a person (or other object of interest) in the building. Sensor(s) 125, 220 may comprise beacons which broadcasts signals that can be read by personal communication devices. The beacons may be bluetooth beacons. The sensor may read signals broadcast from personal information devices, such as MAC addresses or bluetooth information. The sensor may then notice how many personal information devices are within a certain radius. The sensor may use the received signal strength indicator (RSSI) estimate. A controller 110 in the building may then determine a number of people in the building based on how many signals a sensor 125 (or sensors) has noticed. The controller may then use this information to modify state parameters in the defined space 105, such as heat needs, humidity, lighting, security, grounds control, or entertainment, to name a few possibilities.