Access control system using a wearable access sensory implementing an energy harvesting technique

• US 9,831,724 B2
• Filed: 12/02/2015
• Issued: 11/28/2017
• Est. Priority Date: 12/02/2014
• Status: Active Grant

• Current Assignee: Sensormatic Electronics LLC (Johnson Controls International plc)
• Original Assignee: Tyco Fire & Security GmbH (Johnson Controls International plc)
• Inventors: Copeland, Richard L., Sequeira, Melwyn F.
• Primary Examiner(s): Hernandez, William
• Application Number:
  US14/956,803
• Publication Number:
  US 20160156219A1
• Time in Patent Office: 727 Days
• Field of Search: 307 52, 307104
• CPC Class Codes: G07C 9/20 involving the use of a pass
• CPC Class Codes: H02J 50/001 Energy harvesting or scavenging
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves

Abstract

A method for operating a Wearable Access Sensor (“WAS”). The methods comprise: capturing RF energy by the WAS, where the RF energy is emitted within a surrounding environment from equipment disposed at an access point of a restricted area; passing the RF energy through a switch that is normally in a position which provides an electrical connection between an antenna of the WAS and a full wave rectifier of the WAS; performing operations by the WAS to convert the RF energy into direct current for generating electric power; supplying the electric power to an energy storage device of the WAS for charging the energy storage device to a pre-determined voltage level; and supplying power from the energy storage device to a controller of the WAS when a voltage level of the energy storage device is equal to or greater than the pre-determined voltage level.

Claims

1. A method for operating a Wearable Access Sensor (“

WAS”

), comprising;

capturing RF energy by the WAS being worn by a person, where the RF energy is emitted within a surrounding environment from equipment disposed at an access point of a restricted area;

passing the RF energy through a switch that is normally in a position which provides an electrical connection between an antenna of the WAS and a full wave rectifier of the WAS;

performing operations by the WAS to convert the RF energy into direct current for generating electric power;

supplying the electric power to an energy storage device of the WAS for charging the energy storage device to a pre-determined voltage level; and

supplying power from the energy storage device to a controller of the WAS when a voltage level of the energy storage device is equal to or greater than the pre-determined voltage level.

2. The method according to claim 1, wherein the energy storage device comprises a super capacitor.

3. The method according to claim 1, further comprising generating and sending a switch control signal from the controller to the switch to cause the switch to change positions such that the switch is disconnected from the antenna and connected to a transceiver of the WAS.

4. The method according to claim 3, further comprising communicating information from the WAS to a wireless edge device.

5. The method according to claim 4, wherein the information comprises user credentials that are useful for authenticating a user such that the user can be granted or denied access to the restricted area.

6. The method according to claim 1, wherein the power is supplied from the energy storage device to the controller via a voltage converter that changes the pre-determined voltage level to a sub-threshold voltage level.

7. The method according to claim 1, further comprising increasing or decreasing, by a voltage converter of the WAS, a voltage level of a signal received from the energy storage device to a sub-threshold voltage level that is at least one order of magnitude below a normal operating range for the WAS, prior to supplying the power from the energy storage device to the controller.

8. The method according to claim 7, wherein the normal operating range of a voltage level is 1.2 Volts to 3.6 Volts.

9. The method according to claim 7, wherein the sub-threshold voltage level is within 200 milli-Volts to 600 milli-Volts.

10. The method according to claim 1, wherein a directionality of the WAS'"'"'s movement is determined based on at least one of a rate of change of a charging voltage of the energy storage device and a detected direction of travel of the WAS in relation to the access point.

11. A Wearable Access Sensor (“

WAS”

), comprising;

an article wearable on a person;

an electronic circuit coupled to the article and comprising;

an antenna configured to capture RF energy emitted within a surrounding environment from equipment disposed at an access point of a restricted area;

a switch through which the RF energy passes, where the switch is normally in a position which provides an electrical connection between the antenna and a full wave rectifier;

said full wave rectifier configured to convert the RF energy into direct current for generating electric power and to supply the electric power to charge an energy storage device; and

an energy harvester power manager configured to supply power from the energy storage device to a controller when a voltage level of the energy storage device is equal to or greater than a pre-determined voltage level.

12. The WAS according to claim 11, wherein the energy storage device comprises a super capacitor.

13. The method according to claim 11, wherein the controller is configured to generate and send a switch control signal to the switch to cause the switch to change positions such that the switch is disconnected from the antenna and connected to a transceiver of the WAS.

14. The method according to claim 13, wherein the transceiver is configured to communicate information from the WAS to a wireless edge device.

15. The method according to claim 14, wherein the information comprises user credentials that are useful for authenticating a user such that the user can be granted or denied access to the restricted area.

16. The method according to claim 11, wherein the power is supplied from the energy storage device to the controller via a voltage converter that changes the pre-determined voltage level to a sub-threshold voltage level.

17. The method according to claim 11, wherein the voltage level of a signal received from the energy storage device is increased or decreased to a sub-threshold voltage level that is at least one order of magnitude below a normal operating range for the WAS, prior to when the power is supplied from the energy storage device to the controller.

18. The method according to claim 17, wherein the normal operating range of a voltage level is 1.2 Volts to 3.6 Volts.

19. The method according to claim 17, wherein the sub-threshold voltage level is within 200 milli-Volts to 600 milli-Volts.

20. The method according to claim 11, wherein a directionality of the WAS'"'"'s movement is determined based on at least one of a rate of change of a charging voltage of the energy storage device and a detected direction of travel of the WAS in relation to the access point.