Sensor Networks in Buildings Could Use AC Ducts as Huge, Building-Wide Antennas
Wiring large building for fire safety systems, climate control mechanisms, and other public safety monitoring schemes consumes a lot of wire — imagine how much feet of copper connects every room, corridor, stairwell and broom closet in a building like the Empire State. So researchers figured out a far more simplified scheme for creating wireless sensor networks within buildings — why not use the heating, ventilation and air conditioning (HVAC) ducts that are already connecting the entire building as a big antenna that relays data via radio frequency identification (RFID)?
The scheme is rather simple but it could amount to huge cost savings for builders, as it saves the materials and time needed to physically connect sensors within a structure. Take the climate control system for instance. In order to function properly, temperature sensors have to be wired throughout the building to tell the central heating and cooling unit when and where to pipe conditioned air.
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