Radio frequency identification system and related operating methods

1. A method of operating a radio frequency identification (RFID) system, the method comprising:

generating an RFID interrogation signal with an RFID reader of the RFID system;

obtaining, in response to generating the RFID interrogation signal, at least one RFID tag response signal at the RFID reader, the at least one RFID tag response signal conveying tag data, and being received through a first network at a stationary controller; and

providing at least some of the tag data to a mobile device through a second network;

receiving, from the mobile device, a request to locate a particular item of interest having a target RFID tag associated therewith, wherein the at least one RFID tag response signal conveys tag data for the particular item of interest;

determining a location of the target RFID tag relative to the mobile device; and

presenting indicia of the determined location of the target RFID tag at the mobile device;

interrogating the target RFID tag to obtain a first tag response signal, wherein the RFID reader interrogates the target RFID tag;

interrogating a reference RFID tag located at the mobile device to obtain a second tag response signal, wherein the RFID reader interrogates the reference RFID tag; and

calculating a position of the target RFID tag relative to the reference RFID tag, wherein the position is calculated based on the first and second tag response signals.

2. The method of claim 1 , wherein the mobile device is unable to interrogate RFID tags using an RFID over-the-air interface.

3. The method of claim 1 , wherein the mobile device is unable to receive RFID tag response signals using an RFID over-the-air interface.

4. The method of claim 1 , wherein the providing step comprises sending at least some of the tag data from an RFID system controller of the RFID system.

5. The method of claim 1 , wherein the providing step comprises wirelessly transmitting at least some of the tag data from a wireless local area network infrastructure device to the mobile device.

6. The method of claim 1 , wherein the providing step comprises sending at least some of the tag data to a data communication network for routing to the mobile device.

7. The method of claim 1 , further comprising presenting indicia of at least some of the tag data at the mobile device.

8. The method of claim 1 , further comprising:

obtaining a current location of the mobile device; and

filtering the tag data based on the current location of the mobile device to obtain filtered tag data, wherein the at least some of the tag data corresponds to the filtered tag data.

9. The method of claim 1 , wherein the calculating step calculates a distance between the target RFID tag and the reference RFID tag.

10. The method of claim 1 , wherein the calculating step calculates an angle of separation between the target RFID tag and the RFID reader, as measured from the reference RFID tag.

11. The method of claim 1 , further comprising:

obtaining a current location of the mobile device; and

identifying the RFID reader from a plurality of RFID readers in the RFID system, based on the current location of the mobile device.

12. A method of operating a radio frequency identification (RFID) system, the method comprising:

receiving a request through a first network to locate a particular item of interest having a target RFID tag associated therewith, the request originating at a mobile device;

in response to receiving the request, interrogating the target RFID tag with an RFID reader of the RFID system to obtain an RFID tag response signal through a second network from the target RFID tag;

obtaining a current location of the mobile device; and

determining a location of the target RFID tag relative to the current location of the mobile device;

interrogating the target RFID tag with the RFID reader to obtain a first tag response signal;

interrogating a reference RFID tag located at the mobile device to obtain a second tag response signal, wherein the RFID reader interrogates the reference RFID tag; and

calculating a position of the target RFID tag relative to the reference RFID tag, wherein the position is calculated based on the first and second tag response signals.

13. The method of claim 12 , further comprising providing the determined location of the target RFID tag to the mobile device.

14. The method of claim 12 , wherein obtaining the current location of the mobile device comprises receiving current self-position data from the mobile device.

15. A method of operating a radio frequency identification (RFID) system, the method comprising:

receiving a request through a first network to locate a particular item of interest having a target RFID tag associated therewith, the request originating at a mobile device;

in response to receiving the request, interrogating the target RFID tag with an RFID reader of the RFID system to obtain an RFID tag response signal through a second network from the target RFID tag;

obtaining a current location of the mobile device; and

determining a location of the target RFID tag relative to the current location of the mobile device; wherein determining the location of the target RFID tag comprises:

interrogating the target RFID tag with a first RFID reader of the RFID system to obtain a first tag response signal;

interrogating a reference RFID tag located at a second RFID reader of the RFID system to obtain a second tag response signal, wherein the first RFID reader interrogates the reference RFID tag;

obtaining, at the first RFID reader, a distance between the target RFID tag and the second RFID reader, wherein the distance is determined in response to the second RFID reader interrogating the target RFID tag; and

calculating a location of the target RFID tag based on the first tag response signal, the second tag response signal, and the obtained distance.