The optional coupler 242 is provided to securely or removably couple the tag 200 to an item (e.g., object 110 or 112 of FIG. 1). The coupler 242 includes, but is not limited to, a mechanical coupling means (e.g., a strap, clip, clamp, snap) and/or adhesive (e.g., glue or sticker). The coupler 242 is optional since the coupling can be achieved via a weld and/or chemical bond.

The tag 200 can also include a power source 236, an optional Electronic Article Surveillance (“EAS”) component 244, and/or a passive/active/semi-passive RFID component 246. Each of the listed components 236, 244, 246 is well known in the art, and therefore will not be described herein. Any known or to be known battery, EAS component and/or RFID component can be used herein without limitation. The power source 236 can include, but is not limited to, a rechargeable battery and/or a capacitor.

As shown in FIG. 2, the tag 200 further comprises an energy harvesting circuit 232 and a power management circuit 234 for ensuring continuous operation of the tag 200 without the need to change the rechargeable power source (e.g., a battery). In some scenarios, the energy harvesting circuit 232 is configured to harvest energy from one or more sources (e.g., heat, light, vibration, magnetic field, and/or RF energy) and to generate a relatively low amount of output power from the harvested energy. By employing multiple sources for harvesting, the device can continue to charge despite the depletion of a source of energy. Energy harvesting circuits are well known in the art, and therefore will not be described herein. Any known or to be known energy harvesting circuit can be used herein without limitation.