System and methods for monitoring security zones

• US 7,940,177 B2
• Filed: 06/16/2008
• Issued: 05/10/2011
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: Johns Hopkins University
• Original Assignee: Johns Hopkins University
• Inventors: Krill, Jerry A.
• Primary Examiner(s): TRIEU, VAN THANH
• Application Number:
  US12/139,763
• Publication Number:
  US 20100045457A1
• Time in Patent Office: 1,058 Days
• Field of Search: 340/541, 340/545.3, 340/551, 340/552, 340/553, 340/555, 340/556, 340/557, 340/567, 340/539.22, 340/539.26, 340/539.21, 342/28, 709/228
• US Class Current: 340/545.3
• CPC Class Codes: G08B 13/2491 Intrusion detection systems, i.e. where the body of an intruder causes the interference with the electromagnetic field
• CPC Class Codes: G08B 29/188 Data fusion; cooperative systems, e.g. voting among different detectors

Abstract

A security zone is monitored for intrusion detection by dispersing therein a plurality of sensor nodes that, when an intrusion is detected, communicate with their neighboring sensor nodes without protocols other than a first tone. As the intrusion is detected by more sensor nodes, there is an increase in sensor node transmissions and, hence, an increase in the total power density in the security zone which is detected by a remote monitor for detecting and localizing the intrusion and providing an alert. In addition, certain of the sensor nodes also transmit a continuous second tone received by other sensor nodes. When an intrusion occurs, the transmission is blocked causing the receiving nodes to transmit the first tone to alert neighboring nodes.

Claims

1. A security zone monitoring system comprising:

a plurality of sensor nodes dispersed in the security zone, wherein each sensor node transmits a communication without protocols other than a rudimentary language or signal to alert its neighboring sensor nodes when the sensor node detects an intrusion into the security zone and the alerted neighboring sensor nodes that also detect the intrusion transmit the communication to alert their neighboring sensor nodes, the communication continuing to be transmitted by and through the plurality of sensor nodes that detect the intrusion until the intrusion is no longer detected, whereby an increase in the communication transmissions between the plurality of sensor nodes detecting the intrusion increases a total power density in the security zone; and

a transceiver located remotely from the security zone for detecting and localizing the increase in the total power density and for providing an alert of the intrusion.

2. The security zone monitoring system as recited in claim 1, wherein the transmitted communication comprises a first tone.

3. The security zone monitoring system as recited in claim 2, wherein the first tone comprises different frequencies.

4. The security zone monitoring system as recited in claim 2, wherein a portion of the plurality of sensor nodes also transmit a communication comprising a second tone, the second tone being transmitted continuously and being received continuously by neighboring sensor nodes, whereby the intrusion will block the transmission of the second tone thereby causing a receiving neighboring sensor node to detect a resulting drop in the received second tone power and, as a result, to transmit a first tone to its neighboring sensor nodes.

5. The security zone monitoring system as recited in claim 1, wherein the transceiver can modify the programming of the plurality of sensor nodes.

6. The security zone monitoring system as recited in claim 5, wherein the transceiver can modify a detection threshold of the plurality of sensor nodes.

7. The security zone monitoring system as recited in claim 1, wherein a detection threshold of each of the plurality of sensor nodes is pre-set high to ensure a low false alarm rate, the detection threshold being lowered after receiving the communication transmission from a neighboring sensor node.

8. The security zone monitoring system as recited in claim 1, wherein the plurality of sensor nodes are pre-set to search for a specific characteristic.

9. The security zone monitoring system as recited in claim 8, wherein the specific characteristic comprises one of a human voice, a human movement, and a molecule produced by a human.

10. The security zone monitoring system as recited in claim 1, the transceiver further comprising a directional antenna.

11. The security zone monitoring system as recited in claim 10, the system further comprising at least three transceivers for triangulating the received signals to further localize the intrusion location.

12. The security zone monitoring system as recited in claim 1, further comprising one or both of a video camera and an alarm for receiving the alert from the transceiver.

13. The security zone monitoring system as recited in claim 1, wherein the transceiver is one of a microwave transceiver and a millimeter wave transceiver.

14. The security zone monitoring system as recited in claim 1, wherein the transceiver transmits one of infrared, visible, and ultraviolet electromagnetic (EM) waves.

15. The security zone monitoring system as recited in claim 1, further comprising means for accommodating propagation variations of the communication transmissions to maintain the stability and performance of the plurality of sensor nodes.

16. The security zone monitoring system as recited in claim 15, the means for accommodating comprising means for monitoring the false alarms by the plurality of sensor nodes.

17. The security zone monitoring system as recited in claim 15, the means for accommodating comprising one or both of sensitivity time control and automatic gain control.

18. The security zone monitoring system as recited in claim 1, each of the plurality of sensor nodes comprising:

a small sensor;

a power supply;

a transceiver;

a controller integrated circuit; and

a container for protecting and disguising the sensor node.

19. The security zone monitoring system as recited in claim 18, each sensor node further comprising a solar array.

20. The security zone monitoring system as recited in claim 18, wherein the small specific sensor comprises one or more of acoustic, chemical, optical, and biological.

21. The security zone monitoring system as recited in claim 18, further comprising means for determining the direction of the received communication.

22. The security zone monitoring system as recited in claim 18, wherein the transceiver is one of a microwave transceiver and a millimeter wave transceiver.

23. The security zone monitoring system as recited in claim 18, wherein the transceiver transmits one of infrared, visible, and ultraviolet electromagnetic (EM) waves.

24. A security zone monitoring system comprising:

a plurality of transmitters, the transmitters continuously transmitting electromagnetic (EM) waves;

a plurality of receivers randomly dispersed in the security zone for receiving the transmitted EM waves, each of the plurality of receivers able to communicate with its neighboring receivers;

wherein an intrusion into the security zone will block the EM wave transmission of one or more of the EM wave transmitters thereby causing one or more of the receivers to detect a resulting drop in the received EM wave transmissions indicating the presence of the intrusion and to communicate a detection to its neighboring receivers.

25. The security zone monitoring system as recited in claim 24, wherein the plurality of transmitters is one of a microwave transmitter and a millimeter wave transmitter.

26. The security zone monitoring system as recited in claim 24, wherein the plurality of transmitters transmits one of infrared, visible, and ultraviolet electromagnetic (EM) waves.

27. A security zone monitoring system comprising a transceiver located remotely from the security zone for detecting and localizing an increase in the total incoherent power density resulting from communications between a plurality of transmitters located in the security zone when an intrusion is detected by the plurality of transmitters and for providing an alert of the intrusion.

28. A method for monitoring a security zone comprising:

dispersing a plurality of sensor nodes in the security zone;

transmitting a communication without protocols other than a rudimentary language or signal between the plurality of sensor nodes that detect an intrusion into the security zone, the communication continuing to be transmitted by and through the plurality of sensor nodes that detect the intrusion until the intrusion is no longer detected, whereby an increase in the communication transmissions between the plurality of sensor nodes detecting the intrusion increases a total power density in the security zone; and

detecting and localizing the increase in the total power density and providing an alert of the intrusion.

29. The method for monitoring the security zone as recited in claim 28, wherein the transmitted communication comprises a first tone.

30. The method for monitoring the security zone as recited in claim 29, wherein the first tone comprises different frequencies to further localize the intrusion.

31. The method for monitoring the security zone as recited in claim 29, further comprising:

transmitting a communication comprising a second tone between a portion of the plurality of the sensor nodes, the second tone being transmitted continuously;

receiving the second tone continuously by the portion of the plurality of sensor nodes, whereby the intrusion will block the transmission of the second tone thereby causing the receiving portion of the plurality of sensor nodes to detect a resulting drop in the received second tone power and, as a result, to transmit a first tone.

32. The method for monitoring the security zone as recited in claim 28, further comprising modifying the programming of the plurality of sensor nodes.

33. The method for monitoring the security zone as recited in claim 32, wherein the modified programming comprises a detection threshold of the plurality of sensor nodes.

34. The method for monitoring the security zone as recited in claim 28, further comprising:

pre-setting a detection threshold of each of the plurality of sensor nodes high to ensure a low false alarm rate; and

lowering the pre-set detection threshold after receiving the communication transmission.

35. The method for monitoring the security zone as recited in claim 28, further comprising pre-setting the plurality of sensor nodes to search for a specific characteristic.

36. The method for monitoring the security zone as recited in claim 28, further comprising using at least three transceivers for triangulating the received total power density signals to further localize the intrusion location.

37. The method for monitoring the security zone as recited in claim 28, wherein the transmissions are one of a microwave and a millimeter wave.

38. The method for monitoring the security zone as recited in claim 28, wherein the transmissions are one of infrared, visible, and ultraviolet electromagnetic (EM) waves.

39. The method for monitoring the security zone as recited in claim 28, further comprising accommodating propagation variations of the communication transmissions to maintain the stability and performance of the plurality of sensor nodes.

40. The method for monitoring the security zone as recited in claim 39, further comprising monitoring the false alarms by the plurality of sensor nodes.

41. The method for monitoring the security zone as recited in claim 39, further comprising using one or both of sensitivity time control and automatic gain control.

42. A method for monitoring a security zone comprising:

continuously transmitting electromagnetic (EM) waves using a plurality of transmitters; and

receiving the transmitted EM waves using a plurality of receivers, the plurality of receivers being randomly dispersed in the security zone and each of the plurality of receivers being able to communicate with its neighboring receivers;

wherein an intrusion into the security zone will block the EM wave transmission of one or more of the plurality of transmitters thereby causing one or more of the plurality of receivers to detect a resulting drop in the received EM wave transmission indicating the presence of the intrusion and to communicate a detection to its neighboring receivers.

43. The method for monitoring the security zone as recited in claim 42, wherein the transmitter is one of a microwave transmitter and a millimeter wave transmitter.

44. The method for monitoring the security zone as recited in claim 42, wherein the transmitter transmits one of infrared, visible, and ultraviolet EM waves.

45. A method for monitoring a security zone comprising the step of detecting and localizing an increase in a total incoherent power density using a transceiver located remotely from the security zone, the detected and localized power density resulting from communications between a plurality of transmitters located in the security zone when an intrusion is detected by the plurality of transmitters.