Method, system, apparatus, and computer program product for determining a physical location of a sensor

• US 20060242323A1
• Filed: 03/16/2006
• Published: 10/26/2006
• Est. Priority Date: 03/16/2005
• Status: Active Grant

• Current Assignee: Sensus Spectrum, LLC (Xylem, Inc.)
• Original Assignee: Advanced Metering Data Systems Incorporated (Xylem, Inc.)
• Inventors: Sanderford, H. Britton Jr., Larson, Gregg A.
• Granted Patent: US 7,945,626 B2
• Time in Patent Office: Days
• US Class Current: 709/245
• CPC Class Codes: G01S 5/02213 Receivers arranged in a network for determining the position of a transmitter
• CPC Class Codes: H04L 67/12 specially adapted for proprietary or special-purpose networking environments, e.g. medical networks, sensor networks, networks in vehicles or remote metering networks
• CPC Class Codes: H04L 67/52 specially adapted for the location of the user terminal
• CPC Class Codes: H04W 4/02 Services making use of location information
• CPC Class Codes: H04W 4/029 Location-based management or tracking services
• CPC Class Codes: H04W 52/241 taking into account channel quality metrics, e.g. SIR, SNR, CIR, Eb/lo
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

A method that determines a physical location of an unknown position device (UPD) in a communication network including a plurality of known position devices (KDPs), in which a message transmitted by the UPD is received by plural KDPs. The method includes measuring a signal quality of each received message received by the plural KDPs from the UPD, and computing the likely physical location of the UPD based on the physical location of the plural KPDs receiving the message from the UPD and the respective signal quality measured at each KPD.

Claims

1. A method for determining a physical location of an unknown position device (UPD) in a communication network including a plurality of known position devices (KDPs), in which a message transmitted by the UPD is received by plural KDPs, said method comprising:

measuring a signal quality of each received message received by the plural KDPs from the UPD; and

computing the likely physical location of the UPD based on the physical location of the plural KPDs receiving the message from the UPD and the respective signal quality measured at each KPD.

2. The method of claim 1, wherein the measuring a signal quality further comprises measuring at least one of a signal to noise ratio (SNR), a receiver quieting, or a bit error rate (BER).

3. The method of claim 1, wherein the computing further comprises:

performing at least one of a triangulation algorithm, a multilateration algorithm, or a center of mass algorithm to compute the likely physical location of the UPD.

4. The method of claim 1, further comprising:

moving the UPD away from an installed location by an authorized party, the UPD including at least one of a water utility meter, a gas utility meter, or an electric utility meter.

5. The method of claim 1, wherein the computing comprises computing the likely physical location of the UPD based on known locations of KPDs in the communication network.

6. The method of claim 1, further comprising:

receiving a tamper message including a unique identifier of a tampered device in the communication network,

wherein the computing comprises computing the likely physical location of the UPD based on the unique identifier of the tampered device.

7. A method for determining a physical location of an unknown position device (UPD) in a communication network, said method comprising steps of:

receiving first messages from plural known position devices (KPD) in the communication network, each first message including a signal quality of a second message received from the UPD by a respective KPD from which each first message was received; and

computing the physical location of the UPD based on a physical location of each of the plural KPDs, and the signal quality of the second message received from each KPD.

8. The method of claim 7, wherein:

receiving first messages comprises receiving signal quality information based on at least one of a UPD signal to noise ratio (SNR), a UPD receiver quieting, or a UPD bit error rate (BER), as measured at the corresponding KPD, and

the computing further comprises computing the physical location of the UPD based on at least one of the UPD SNR, the UPD receiver quieting, or the UPD BER.

9. The method of claim 7, wherein the computing comprises:

performing at least one of a triangulation algorithm, a multilateration algorithm, or a center of mass algorithm to compute the physical location of the UPD.

10. The method of claim 7, further comprising:

moving the UPD away from an installed location by an authorized party, the UPD including at least one of a water utility meter, a gas utility meter, or an electric utility meter.

11. The method of claim 7, wherein the computing comprises computing the physical location of the UPD based on known locations of KPDs in the communication network.

12. The method of claim 7, further comprising:

receiving a tamper message including a unique identifier of a tampered device in the communication network,

wherein the computing comprises computing the physical location of the UPD based on the unique identifier of the tampered device.

13. A regional network interface (RNI) device in a communication network that includes plural known position devices (KPDs) and an unknown position device (UPD), the RNI comprising:

a receiving unit configured to receive first messages from the plural KPDs in the communication network, each first message including a signal quality of a second message received from the UPD by the respective KPD from which each first message was received; and

a computing unit configured to compute the physical location of the UPD based on a physical location of each of the plural KPDs, and the signal quality of the second message as received from each KPD.

14. The RNI of claim 13, wherein:

the receiving unit is further configured to receive the first messages including signal quality information based on at least one of a UPD signal to noise ratio (SNR), a UPD receiver quieting, or a UPD bit error rate (BER), each as measured at the corresponding KPD, and

the computing unit is further configured to compute the physical location of the UPD based on at least one of the UPD SNR, the UPD receiver quieting, or the UPD BER, each as measured at the KPD.

15. The RNI of claim 13, wherein the computing unit is configured to perform at least one of a triangulation algorithm, a multilateration algorithm, or a center of mass algorithm to compute the physical location of the UPD.

16. The RNI of claim 13, wherein the computing unit is further configured to compute the physical location of the UPD based on known locations of KPDs in the communication network.

17. The RNI of claim 13, further comprising:

a tamper message receiving unit configured to receive a tamper message including an ID of a tampered device in the communication network,

wherein the computing unit is further configured to compute the physical location of the UPD based on the ID of the tampered device.

18. A known position device (KPD) having a known physical location in a communication network, said KPD comprising:

a receiver configured to receive a first message from an unknown position device (UPD);

a measurement unit configured to measure a received signal quality of the first message; and

a transmitter unit configured to transmit a second message including the received signal quality to a regional network interface (RNI).

19. The KPD of claim 18, wherein the measurement unit is further configured to measure the received signal quality based on at least one of a UPD signal to noise ratio (SNR), a UPD receiver quieting, or a UPD bit error rate (BER), and

the transmitter unit is further configured to transmit the second message including at least one of the UPD SNR, the UPD receiver quieting, or the UPD BER.

20. The KPD of claim 18, wherein the transmitter unit is further configured to delay a transmission of the second message by a random delay time.

21. The KPD of claim 18, wherein the transmitter unit is further configured to delay a transmission of the second message by a time based on the received signal quality measured by the measurement unit.

22. The KPD of claim 18, wherein the transmitter unit is further configured to delay a transmission of the second message by a time that is inversely related to the received signal quality measured by the measurement unit.

23. A computer program product storing program instructions which when executed by a computer to determine a physical location of an unknown position device (UPD) in a communication network, results in performing steps comprising:

receiving first messages from plural known position devices (KPD) in the communication network, each first message including a signal quality of a second message received from the UPD by a respective KPD from which each first message was received; and

computing the physical location of the UPD based on a physical location of each of the plural KPDs, and the signal quality of the second message as received from each KPD.

24. A communication system comprising:

an unknown position device (UPD) configured to transmit a first message;

plural known position devices (KPD) located at known physical locations, each KPD including,

a KPD receiver unit configured to receive the first message from the unknown position device (UPD),

a measurement unit configured to measure a received signal quality of the first message, and

a transmitter unit configured to transmit a second message including the signal quality measured by the measurement unit; and

a regional network interface (RNI) including,

an RNI receiving unit configured to receive second messages from the KPDs, each of the second messages including the signal quality measured at the respective KPD, and

a computing unit configured to compute a physical location of the UPD based on the known physical location of each KPD and the signal quality of the first message measured at the respective KPD.