Alarm systems, remote communication devices, and article security methods

1. An alarm system comprising:

a base communication device configured to implement wireless communications;

a remote communication device configured to communicate with the base communication device using the wireless communications, wherein the remote communication device is adapted to be associated with an article to be secured and wherein the remote communication device comprises alarm circuitry;

wherein the remote communication device is configured to generate a first signal responsive to one of the wireless communications of the base communication device and wherein the first signal comprises a characteristic configured to identify the first signal as being generated responsive to wireless communications of the base communication device;

wherein the remote communication device is configured to generate a second signal responsive to the reception of spurious electromagnetic energy by the remote communication device and wherein the second signal comprises the characteristic; and

wherein the remote communication device is configured to distinguish the first signal from the second signal and to generate a human perceptible alarm signal responsive to the distinguishing and the generation of the first signal.

2. The system of claim 1 wherein the base communication device is configured to implement the wireless communications including generation of the wireless communications within a secured area and the remote communication device is configured to generate the first signal responsive to the presence of the remote communication device in the secured area and the reception of the wireless communications by the remote communication device.

3. The system of claim 2 wherein the base communication device is positioned to emit the wireless signal to define the secured area adjacent to a point of ingress and egress of a defined area wherein the article is secured.

4. The system of claim 1 wherein the wireless communications of the base communication device are within a frequency band and the spurious electromagnetic energy occurs at a frequency outside of the frequency band.

5. The system of claim 4 wherein the remote communication device comprises monitoring circuitry tuned to the frequency of the spurious electromagnetic energy and not tuned to the frequency band.

6. The system of claim 5 wherein the remote communication device is configured to utilize output of the monitoring circuitry to distinguish the first signal from the second signal.

7. The system of claim 6 wherein the remote communication device is configured to identify the first signal by an absence of detected electromagnetic energy by the monitoring circuitry.

8. The system of claim 1 wherein the remote communication device is configured to not generate the human perceptible alarm signal during the presence of the second signal.

9. The system of claim 1 wherein the remote communication device comprises an antenna circuit consisting essentially of a parallel LC resonant circuit configured to resonate with wireless communications emitted from the base communication device.

10. The system of claim 1 wherein the base communication device and the remote communication device are configured to communicate using the wireless communications having a frequency less than 55 MHz.

11. A remote communication device comprising:

a housing configured to be coupled with an article to be secured;

alarm circuitry coupled with the housing;

an antenna circuit coupled with the housing and configured to receive a plurality of wireless signals emitted at a plurality of different moments in time from a base communication device associated with the remote communication device to form an alarm system;

conditioning circuitry configured to generate a plurality of electrical signals corresponding to the wireless signals;

monitoring circuitry configured to monitor for the presence of spurious electromagnetic energy at the remote communication device; and

processing circuitry coupled with the conditioning circuitry and the monitoring circuitry and configured to identify some of the electrical signals as corresponding to wireless signals communicated by a base communication device responsive to the monitoring by the monitoring circuitry, and wherein the processing circuitry is configured to control the alarm circuitry to generate a plurality of human perceptible alarm signals corresponding to respective ones of the identified some of the electrical signals.

12. The device of claim 11 wherein the conditioning circuitry comprises a non-linear device configured to generate the electrical signals.

13. The device of claim 11 wherein the antenna circuit is tuned to receive the wireless signals individually having a frequency less than 55 MHz.

14. The device of claim 11 wherein the antenna circuit consisting essentially of a parallel LC resonant circuit configured to resonate with the wireless signals.

15. The device of claim 11 wherein the antenna circuit is tuned to receive the wireless signals within a frequency band used by the base communication device, and the monitoring circuitry is configured to monitor for the presence of the spurious electromagnetic energy having a frequency outside of the frequency band.

16. The device of claim 11 wherein the antenna circuit is tuned to receive the wireless signals within a frequency band used by the base communication device, and the monitoring circuitry is tuned to a frequency range outside of the frequency band.

17. The device of claim 11 wherein the monitoring circuitry is tuned to receive the wireless signals outside of a frequency band used by the base communication device.

18. The device of claim 11 wherein the processing circuitry is configured to identify the some of the electrical signals by an absence of detected spurious electromagnetic energy by the monitoring circuitry at respective moments in time when the wireless signals corresponding to the some of the electrical signals are received by the remote communication device.

19. The device of claim 11 wherein the processing circuitry is configured to not control the generation of the human perceptible alarm signal during the presence of the spurious electromagnetic energy detected by the monitoring circuitry.

20. An article security method comprising:

associating a remote communication device with an article to be secured;

using the remote communication device, receiving spurious electromagnetic energy and wireless signals of a base communication device associated with the remote communication device to form an alarm system;

analyzing the received spurious electromagnetic energy and the received wireless signals with respect to criteria usable to identify the wireless signals of the base communication device;

indicating satisfaction of the criteria corresponding to individual ones of the received spurious electromagnetic energy and the wireless signals;

distinguishing the satisfied criteria indications resulting from the wireless signals of the base communication device from the satisfied criteria indications resulting from the spurious electromagnetic energy; and

responsive to the distinguishing, generating a plurality of human perceptible alarm signals corresponding to the satisfied criteria indications resulting from the wireless signals of the base communication device.

21. The method of claim 20 further comprising, using the base communication device, emitting the wireless signals towards a point of ingress and egress of a defined area wherein the article is secured and wherein the receiving the wireless signals of the base communication device comprises receiving using the remote communication device positioned adjacent to the point of ingress and egress of the defined area.

22. The method of claim 20 further comprising, using the base communication device, emitting the wireless signals within a frequency band, and the receiving the spurious electromagnetic energy comprises receiving the spurious electromagnetic energy having a frequency outside of the frequency band.

23. The method of claim 22 wherein the receiving the spurious electromagnetic energy comprises receiving using circuitry tuned to the frequency of the spurious electromagnetic energy and not tuned to the frequency band.

24. The method of claim 23 wherein the distinguishing comprises distinguishing using the circuitry tuned to the frequency of the spurious electromagnetic energy.

25. The method of claim 24 wherein the distinguishing comprises identifying the satisfied criteria indications resulting from the wireless signals of the base communication device by an absence of spurious electromagnetic energy received by the circuitry.

26. The method of claim 23 wherein the generating comprises not generating the human perceptible alarm signals during the presence of the spurious electromagnetic energy received by the circuitry.

27. The method of claim 20 further comprising, using the base communication device, emitting the wireless signals and wherein the receiving comprises receiving using an antenna circuit of the remote communication device consisting essentially of a parallel LC resonant circuit configured to resonate with the wireless signals emitted from the base communication device.

28. The method of claim 20 further comprising, using the base communication device, emitting the wireless signals having a frequency less than 55 MHz.

29. An article security method comprising:

associating a remote communication device with an article to be secured;

using the remote communication device, generating a plurality of electrical signals responsive to receipt of spurious electromagnetic energy and a plurality of wireless signals of a base communication device associated with the remote communication device to form an alarm system;

distinguishing the electrical signals generated responsive to the spurious electromagnetic energy from electrical signals generated responsive to the wireless signals of the base communication device; and

responsive to the distinguishing, generating a plurality of human perceptible alarm signals corresponding to respective ones of the electrical signals generated responsive to the wireless signals of the base communication device.

30. The method of claim 29 further comprising, using the base communication device, emitting the wireless signals towards a point of ingress and egress of a defined area wherein the article is secured and wherein the receiving the wireless signals of the base communication device comprises receiving using the remote communication device positioned adjacent to the point of ingress and egress of the defined area.

31. The method of claim 29 further comprising:

using the base communication device, emitting the wireless signals within a frequency band; and

receiving the spurious electromagnetic energy having a frequency outside of the frequency band.

32. The method of claim 31 wherein the receiving the spurious electromagnetic energy comprises receiving using circuitry tuned to the frequency of the spurious electromagnetic energy and not tuned to the frequency band.

33. The method of claim 32 wherein the distinguishing comprises distinguishing using the circuitry tuned to the frequency of the spurious electromagnetic energy.

34. The method of claim 33 wherein the distinguishing comprises identifying the electrical signals resulting from the wireless signals of the base communication device by an absence of spurious electromagnetic energy received by the circuitry.

35. The method of claim 32 wherein the generating comprises not generating the human perceptible alarm signals during the presence of the spurious electromagnetic energy received by the circuitry.

36. The method of claim 29 further comprising:

using the base communication device, emitting the wireless signals; and

using the remote communication device, receiving the wireless signals using an antenna circuit consisting essentially of a parallel LC resonant circuit configured to resonate with the wireless signals emitted from the base communication device.

37. The method of claim 29 further comprising, using the base communication device, emitting the wireless signals having a frequency less than 55 MHz.