초록 ▼

A theft detection system includes an accelerometer attachable to an object, the accelerometer providing an acceleration signal in response to movement of the object; an alarm mechanism for providing a signal in response to movement of the object; and for preventing false alarms, a filter programmed

A theft detection system includes an accelerometer attachable to an object, the accelerometer providing an acceleration signal in response to movement of the object; an alarm mechanism for providing a signal in response to movement of the object; and for preventing false alarms, a filter programmed to determine the frequency of the acceleration signal and to provide an output to activate the alarm mechanism only when the frequency of the acceleration signal meets a predetermined criteria.

대표청구항 ▼

1. A theft detection and deterrence system comprising:an accelerometer attachable to an object, wherein the accelerometer measures the acceleration of the object and provides an acceleration signal in response to motion of the object;a processor for processing the acceleration signal to determine if

1. A theft detection and deterrence system comprising:an accelerometer attachable to an object, wherein the accelerometer measures the acceleration of the object and provides an acceleration signal in response to motion of the object;a processor for processing the acceleration signal to determine if the motion of the object is a hostile motion and wherein the processor provides a corresponding output;a hostility state machine responsive to the output of the processor comprising:a non-hostility state and a hostility state, the hostility state comprising an initial hostility state level and at least a subsequent hostility state level, wherein the non-hostility state represents a not-stolen status and the hostility state represents a stolen status and wherein the hostility state machine determines a current hostility state level;means for decreasing the current hostility state level when at the at least a subsequent hostility state level to the initial hostility state level; andan alarm subsystem responsive to the control signal providing an alarm signal in response to hostile motion.2. The theft detection and deterrence system of claim 1, wherein the processor further comprises a filter configured to pass acceleration signals in a specified frequency range.3. The theft detection and deterrence system of claim 2, wherein the processor further comprises a means for determining the frequency of the acceleration signal by performing spectral analysis of the acceleration signal.4. The theft detection and deterrence system of claim 3, wherein the processor further comprises a means for counting how often the frequency of the acceleration signal is within a specified range and providing a corresponding output.5. The theft detection and deterrence system of claim 3, wherein the state machine adjusts the current state when the frequency of the acceleration signal is within a predetermined range.6. The theft detection and deterrence system of claim 1, wherein the processor further comprises:a means for calculating the deviation of the amplitude of the acceleration signal in a predetermined time frame; anda means for comparing the deviation of the amplitude of the acceleration signal in a predetermined time frame with a predetermined threshold and providing a corresponding output.7. The theft detection and deterrence system of claim 6, wherein the processor further comprises means for counting how often the deviation of the amplitude of the acceleration signal exceeds the predetermined threshold.8. The theft detection and deterrence system of claim 6, wherein the state machine adjusts the current state when the deviation of the amplitude of the acceleration signal exceeds a predetermined threshold.9. The theft detection and deterrence system of claim 1, wherein the state machine comprises five hostility states.10. The theft detection and deterrence system of claim 9, wherein the first hostility state represents a not stolen status, a second hostility state represents a first level warning status, a third hostility state represents a second level warning status, a fourth hostility state represents a third level warning status, and the final hostility state represents a stolen status.11. The theft detection and deterrence system of claim 1, wherein the alarm subsystem comprises an audible alarm having an audible tone that indicates the current hostility state.12. The theft detection and deterrence system of claim 1, wherein the alarm subsystem comprises an audible alarm.13. The theft detection and deterrence system of claim 1, wherein the alarm subsystem comprises a means for disabling a computer.14. The theft detection and deterrence system of claim 13, wherein the state machine comprises five hostility states.15. The theft detection and deterrence system of claim 14, wherein the first hostility state represents a not stolen status, a second hostility state represents a first level warning status, a third hostility state represents a second level warning status, a fourth hostility state represents a third level warning status, and the final hostility state represents a stolen status.16. A theft detection and deterrence system comprising:an accelerometer attachable to an object, wherein the accelerometer measures the acceleration of the object and provides an acceleration signal in response to motion of the object;a circuit for processing the acceleration signal to determine if the motion of the object is a hostile motion and wherein the circuit provides a corresponding output;a hostility state machine responsive to the output of the circuit comprising:a non-hostility state and a hostility state, the hostility state comprising an initial hostility state level and at least a subsequent hostility state level, wherein the non-hostility state represents a not-stolen status and the hostility state represents a stolen status and wherein the hostility state machine determines a current hostility state level;means for decreasing the current hostility state level when at the at least a subsequent hostility state level to the initial hostility state level; andan alarm subsystem responsive to the control signal for providing an alarm signal in response to hostile motion.17. The theft detection and deterrence system of claim 16, wherein the circuit further comprises a filter configured to pass acceleration signals in a specified frequency range.18. The theft detection and deterrence system of claim 17, wherein the circuit further comprises a means for determining the frequency of the acceleration signal by performing spectral analysis of the acceleration signal.19. The theft detection and deterrence system of claim 18, wherein the circuit further comprises a means for counting how often the frequency of the acceleration signal is within a specified range and providing a corresponding output.20. The theft detection and deterrence system of claim 18, wherein the state machine adjusts the current state when the frequency of the acceleration signal is within a predetermined range.21. The theft detection and deterrence system of claim 16, wherein the circuit further comprises:a means for calculating the deviation of the amplitude of the acceleration signal in a predetermined time frame; anda means for comparing the deviation of the amplitude of the acceleration signal in a predetermined time frame with a predetermined threshold and providing a corresponding output.22. The theft detection and deterrence system of claim 21, wherein the circuit further comprises means for counting how often the deviation of the amplitude of the acceleration signal exceeds the predetermined threshold.23. The theft detection and deterrence system of claim 21, wherein the state machine adjusts the current state when the deviation of the amplitude of the acceleration signal exceeds a predetermined threshold.24. The theft detection and deterrence system of claim 16, wherein the alarm subsystem comprises an audible alarm having an audible tone that indicates the current hostility state.25. The theft detection and deterrence system of claim 16, wherein the alarm subsystem comprises an audible alarm.26. The theft detection and deterrence system of claim 16, wherein the alarm subsystem comprises a means for disabling a computer.27. A theft detection and deterrence method comprising the steps of:attaching an accelerometer to an object, wherein the accelerometer measures the acceleration of the object and provides an acceleration signal in response to motion of the object;programming a processor for processing the acceleration signal to determine if the motion of the object is a hostile motion and wherein the processor provides a corresponding output;providing a hostility state machine responsive to the output of the processor, wherein the state machine comprises a non-hostility state and a hostility state, the hostility state comprising an initial hostility state level and at least a subsequent hostility state level, wherein the non-hostility state represents a not-stolen status and the hostility state represents a stolen status and wherein the hostility state machine determines a current hostility state level;means for decreasing the current hostility state level when at the at least a subsequent hostility state level to the initial hostility state level; andproviding an alarm subsystem responsive to the control signal for providing an alarm signal in response to hostile motion.28. The theft detection and deterrence method of claim 27, further comprising the step of programming the processor to pass acceleration signals in a specified frequency range.29. The theft detection and deterrence method of claim 28, further comprising the step of programming the processor to determine the frequency of the acceleration signal by performing spectral analysis of the acceleration signal.30. The theft detection and deterrence method of claim 29, further comprising the step of programming the processor to count how often the frequency of the acceleration signal is within a specified range and to provide a corresponding output.31. The theft detection and deterrence method of claim 27, further comprising the step of configuring the state machine to adjust the current state when the frequency of the acceleration signal is within a predetermined range.32. The theft detection and deterrence method of claim 27, further comprising the steps of:programming the processor to calculate the deviation of the amplitude of the acceleration signal in a predetermined time frame; andprogramming the processor to compare the deviation of the amplitude of the acceleration signal in a predetermined time frame with a predetermined threshold and to provide a corresponding output.33. The theft detection and deterrence method of claim 32, further comprising the step of programming the processor to count how often the deviation of the amplitude of the acceleration signal exceeds the predetermined threshold.34. The theft detection and deterrence method of claim 32, further comprising the step of configuring the state machine to adjust the current state when the deviation of the amplitude of the acceleration signal exceeds a predetermined threshold.35. The theft detection and deterrence method of claim 27, further comprising the step of configuring the state machine to comprise five hostility states.36. The theft detection and deterrence method of claim 35, wherein the five hostility states comprise the first hostility state representing a not stolen status, a second hostility state representing a first level warning status, a third hostility state representing a second level warning status, a fourth hostility state representing a third level warning status, and the final hostility state representing a stolen status.37. The theft detection and deterrence method of claim 27, further comprising the step of configuring the alarm subsystem to comprise an audible alarm having an audible tone that indicates the current hostility state.38. The theft detection and deterrence method of claim 27, further comprising the step of configuring the alarm subsystem to comprise an audible alarm.39. The theft detection and deterrence method of claim 27, further comprising the step of configuring the alarm subsystem to comprise a means for disabling a computer.40. A theft detection and deterrence method comprising the steps of:attaching an accelerometer to an object, wherein the accelerometer measures the acceleration of the object and provides an acceleration signal in response to motion of the object;configuring a circuit for processing the acceleration signal to determine if the motion of the object is a hostile motion and wherein the circuit provides a corresponding output;providing a hostility state machine responsive to the output of the circuit, wherein the state machine comprises a non-hostility state and a hostility state, the hostility state comprising an initial hostility state level and at least a subsequent hostility state level, wherein the non-hostility state represents a not-stolen status and the hostility state represents a stolen status and wherein the hostility state machine determines a current hostility state level;means for decreasing the current hostility state level when at the at least a subsequent hostility state level to the initial hostility state level; andproviding an alarm subsystem responsive to the control signal for providing an alarm signal in response to hostile motion.41. The theft detection and deterrence method of claim 40, further comprising the step of configuring the circuit to pass acceleration signals in a specified frequency range.42. The theft detection and deterrence method of claim 41, further comprising the step of configuring the circuit to determine the frequency of the acceleration signal by performing spectral analysis of the acceleration signal.43. The theft detection and deterrence method of claim 42, further comprising the step of configuring the circuit to count how often the frequency of the acceleration signal is within a specified range and to provide a corresponding output.44. The theft detection and deterrence method of claim 42, further comprising the step of configuring the state machine to adjust the current state when the frequency of the acceleration signal is within a predetermined range.45. The theft detection and deterrence method of claim 40, further comprising the steps of:configuring the circuit to calculate the deviation of the amplitude of the acceleration signal in a predetermined time frame; andconfiguring the circuit to compare the deviation of the amplitude of the acceleration signal in a predetermined time frame with a predetermined threshold and to provide a corresponding output.46. The theft detection and deterrence method of claim 45, further comprising the step of configuring the circuit to count how often the deviation of the amplitude of the acceleration signal exceeds the predetermined threshold.47. The theft detection and deterrence method of claim 45, further comprising the step of configuring the state machine to adjust the current state when the deviation of the amplitude of the acceleration signal exceeds a predetermined threshold.48. The theft detection and deterrence method of claim 40, further comprising the step of configuring the state machine to comprise five hostility states.49. The theft detection and deterrence method of claim 48, wherein the five hostility states comprise the first hostility state representing a not stolen status, a second hostility state representing a first level warning status, a third hostility state representing a second level warning status, a fourth hostility state representing a third level warning status, and the final hostility state representing a stolen status.50. The theft detection and deterrence method of claim 40, further comprising the step of configuring the alarm subsystem to comprise an audible alarm having an audible tone that indicates the current hostility state.51. The theft detection and deterrence method of claim 40, further comprising the step of configuring the alarm subsystem to comprise an audible alarm.52. The theft detection and deterrence method of claim 40, further comprising the step of configuring the alarm subsystem to comprise a means for disabling a computer.53. A theft detection and deterrence system comprising:a hostility state machine comprising:a non-hostility state and a hostility state, the hostility state comprising an initial hostility state level and at least a subsequent hostility state level, wherein the non-hostility state represents a not-stolen status and the hostility state represents a stolen status and wherein the hostility state machine determines a current hostility state level; andmeans for decreasing the current hostility state level when at the at least a subsequent hostility state level to the initial hostility state level.