Patent attributes
A method, system and tag for low power radio frequency communication is described. In one embodiment, the RF tag comprises: an energy harvesting unit operable to convert incident RF energy to direct current (DC); a storage unit operable to store recovered DC power; a passive wakeup pattern detector operable to generate an interrupt in response to detecting a set of one or more subcarriers; one or more sensors for sensing; a communication mechanism; and a microcontroller coupled to the energy harvesting and storage units, the one or more sensors, and the backscatter communicator, the microcontroller operable to wake up from a sleep state in response to the interrupt and cause the communication mechanism to exchange data wirelessly with another while powered by energy previously harvested and stored by the energy harvesting and storage unit.