Tampering detection for an electric meter

• US 9,506,950 B2
• Filed: 03/17/2014
• Issued: 11/29/2016
• Est. Priority Date: 03/17/2014
• Status: Active Grant

• Current Assignee: Landis+Gyr Inc. (Landis+Gyr Group AG)
• Original Assignee: Landis+Gyr Inc. (Landis+Gyr Group AG)
• Inventors: Ramirez, Anibal Diego
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): Zhang, Haidong
• Application Number:
  US14/215,445
• Publication Number:
  US 20150260759A1
• Time in Patent Office: 988 Days
• US Class Current: 1/1
• CPC Class Codes: G01R 11/24 Arrangements for avoiding or indicating fraudulent use
• CPC Class Codes: G01R 22/066 Arrangements for avoiding or indicating fraudulent use
• CPC Class Codes: G06Q 50/06 Energy or water supply

Abstract

A tamper detection system for an electricity meter includes an antenna, an RF signal level circuit, and a controller. The antenna is configured to receive an RF signal. The RF signal level circuit is supported within an electricity meter housing and is operatively connected to the antenna. The RF signal level circuit is configured to detect the RF signal received by the antenna and to provide a strength signal corresponding to a magnitude of the RF signal. The controller is supported within the electricity meter housing, and is operatively connected to the RF signal level circuit. The controller is configured to generate an RF signal strength value based at least in part on the strength signal, and to generate a tamper flag responsive at least in part to a determination that the RF signal strength value exceeds a threshold value.

Claims

1. A tamper detection system for an electricity meter, comprising:

an antenna configured to receive an RF signal;

an RF signal level circuit supported within an electricity meter housing and operatively connected to the antenna, the RF signal level circuit configured to detect the RF signal and to provide a strength signal corresponding to a magnitude of the RF signal received by the antenna;

a controller supported within the electricity meter housing, operatively connected to the RF signal level circuit, the controller configured to;

generate an RF signal strength value based at least in part on the strength signal;

generate a tamper flag responsive at least in part to a determination that the RF signal strength value exceeds a threshold value;

wherein the RF signal level circuit includes RF peak detector circuit operatively connected to the antenna, the RF peak detector circuit configured to provide a signal component of the RF signal; and

wherein the RF signal level circuit includes a discharge circuit operatively connected to the RF peak detector circuit and configured to receive the component of the RF signal, wherein the discharge circuit is configured to provide the strength signal.

2. The tamper detection system of claim 1, further comprising an RF filter circuit interposed between the discharge circuit and the controller, wherein the RF filter circuit is configured to remove an RF component from the strength signal prior to being compared at the controller.

3. The tamper detection system of claim 1, further comprising a memory operatively connected to the controller and configured to store the tamper flag responsive at least in part to a determination that the RF signal strength value exceeds a threshold value.

4. The tamper detection system of claim 3, further comprising a communication circuit operatively connected to the memory, wherein the controller is further configured to generate the tamper flag by causing the communication circuit to transmit the stored tamper flag external to the electricity meter.

5. The tamper detection system of claim 4, wherein the memory is configured to store programmed instructions;

and

wherein the controller is configured to execute the programmed instructions stored in the memory.

6. The tamper detection system of claim 5, wherein the controller includes an analog to digital converter configured to convert the strength signal to a digital signal for comparison to the threshold value.

7. The tamper detection system of claim 1, wherein the discharge circuit comprises a first resistor operably coupled between the RF peak detector circuit and ground.

8. The tamper detection system of claim 1, wherein the controller is configured to provide a control signal to the discharge circuit, wherein the control signal adjusts a configuration of the strength signal.

9. The tamper detection system of claim 8, wherein the discharge circuit comprises a first resistor operably coupled between the RF peak detector circuit and ground, and a second resistor operably coupled to the RF peak detector circuit, the second resistor further operatively coupled to receive the control signal from the controller.

10. The tamper detection system of claim 8, further comprising a memory operatively connected to the controller and configured to store the tamper flag responsive at least in part to a determination that the RF signal strength value exceeds a threshold value.

11. The tamper detection system of claim 10, further comprising a communication circuit operatively connected to the memory, wherein the controller is further configured to generate the tamper flag by causing the communication circuit to transmit the stored tamper flag external to the electricity meter.

12. The tamper detection system of claim 11, wherein the memory is configured to store programmed instructions;

and

wherein the controller is configured to execute the programmed instructions stored in the memory.

13. The tamper detection system of claim 12, wherein the controller includes an analog to digital converter configured to convert the strength signal to a digital signal for comparison to the threshold value.

14. The tamper detection system of claim 13, wherein the discharge circuit comprises a first resistor operably coupled between the RF peak detector circuit and ground, and a second resistor operably coupled to the RF peak detector circuit, the second resistor further operatively coupled to receive the control signal from the controller.