Power source system for RF location/identification tags

#Radio Frequency (“RF”) device, such as RF identification device, has become an important implementation of an Automatic Identification technique. The object of any RF system is to carry data suitable transponders, generally known as tags, and to retrieve data, by machine-readable means, at a desired time and place to satisfy particular application needs.

#Data within a tag may provide identification for an item in manufacture, goods in transit, a location, the identity of a vehicle, an animal, individual, etc. Additional data may be provided for supporting applications through item specific information or instructions immediately available on reading the tag. For example, the color of paint for a car body entering a paint spray area on the production line, the set-up instructions for a flexible manufacturing cell or the manifest to accompany a shipment of goods. In other cases, information may be obtained, indirectly, merely by observing the characteristics of the tags' transmissions-signal strength, multipath delay profile, or time of arrival, for example. RF technologies vary widely in frequency, packaging, performance, and cost.

#FIG. 1 shows a conventional RF system 1 which includes an RF tag 10 (e.g., an RFID tag) and an RF arrangement 2 for reading or interrogating the tag 10. The arrangement 2 communicates with a data processing unit 3 to exchange data with the tag 10. The system 1 may also include a facility (not shown) for entering or programming data into the tag 10, if this is not undertaken at source by the manufacturer of the tag 10.

#FIG. 1 shows a conventional RF system;

#FIG. 2 shows an exemplary embodiment of an active RF tag according to the present invention;

#FIG. 3 shows another exemplary embodiment of an active RF tag according to the present invention;

#According to present invention, an active RF tag is adapted to obtain power from a viable alternative to a full reliance on a stand alone battery. The power may be obtained from a variety of sources, for example, direct, in-line, inductive and/or solar power sources which are described in detail below.

#FIG. 2 shows an exemplary embodiment of a device 22 including a RF tag 10a according to the present invention. The device 22 has a serial interface connector 20 which may be used to obtain or provide data and power for RF tag 10a. The RF tag 10a, situated inside the device 22, obtains its power source feeding the power in connection of the serial interface 20. Those skilled in the art would understand that power may be obtained from any type of interface connector which transmits power, such as, Universal Serial Bus (“USB”), a “firewire” (i.e., IEEE 1394), parallel, microphone, etc.

#Examples of products which enable such tags are laptops, personal digital assistance (PDAs), medical equipment, etc. These devices generally have the type of connections described above. Thus, a RF device such as exemplary device 22 may acquire power from the target device (e.g., laptop, PDA) via the appropriate connection. In this manner, the power supply of the target device does not need to be disturbed. Those of skill in the art will understand that some minor modifications of the target device software may be needed to activate the port or connection where the RF tag 10a is connected.