| 摘要 |
A circular data-bearing medium 942) having a hub hole (43) has a chip (37) and two distinct loop antennas (32), each offset from the other, each antenna (32) disposed around the hub hole (43), the chip (37) electrically connected with each of the two distinct antennas (32). The circular data-bearing medium (42) does not have a battery. When bathed in RF energy the chip (37) receives power from one of the loop antennas (32). During the power-up time the chip (37) may receive message on the other of the loop antennas (32), and may respond, on that antenna (32), to some of the received messages and not others, based upon internal state within the chip (37). At least one of the internal states is reset upon loss and restoration of the bathing RF every. When passed nearby to an EAS sensor, for example at an xit of a sort, the chip (37) can selectively either trigger the sensor or not trigger the sensor, as a function of whether an EAS link has or has not been blown, and the triggering response is non-identical from one data-bearing medium (42) to the next. |
