Is this possible—and, if so, who makes such tags?
I assume you are asking if an RFID chip can be connected to two separate antennas in order to create a transponder or tag. The answer is “yes.” The Monza X-2K Dura and Monza X-8K Dura, both from Impinj, support two independent antennas—a short-range loop antenna on the circuit board and a long-range dipole antenna inside the electronic device’s enclosure. This allows the chip to be read from both the near field (on a manufacturing line, for example) and at long range (within a warehouse). I believe there may be other chips with four pads for connecting two antennas.
—Mark Roberti, Founder and Editor, RFID Journal
Can an RFID Tag Provide Information About the Contents of a Box? »