Cell isolation through quasi-orthogonal sequences in a frequency hopping network

• US 7,965,758 B2
• Filed: 09/10/2007
• Issued: 06/21/2011
• Est. Priority Date: 09/15/2006
• Status: Active Grant

• Current Assignee: Itron Global Sarl (Itron, Inc.)
• Original Assignee: Itron, Inc.
• Inventors: Picard, Gilles
• Primary Examiner(s): Pham; Chi H
• Assistant Examiner(s): Ng; Fan
• Application Number:
  US11/900,203
• Publication Number:
  US 20080089390A1
• Time in Patent Office: 1,380 Days
• Field of Search: None
• US Class Current: 375/130
• CPC Class Codes: G01D 4/004 Remote reading of utility meters to a fixed location
• CPC Class Codes: G01D 4/006 Remote reading of utility meters to a non-fixed location, i.e. mobile location
• CPC Class Codes: G08C 19/16 in which transmission is by pulses
• CPC Class Codes: H04B 1/7143 Arrangements for generation of hop patterns
• CPC Class Codes: H04B 17/318 Received signal strength
• CPC Class Codes: H04B 7/15 Active relay systems
• CPC Class Codes: H04L 45/127 based on intermediate node capabilities
• CPC Class Codes: H04W 40/005 Routing actions in the presence of nodes in sleep or doze mode
• CPC Class Codes: H04W 40/10 based on available power or energy
• CPC Class Codes: H04W 40/22 using selective relaying for reaching a BTS [Base Transceiver Station] or an access point
• CPC Class Codes: H04W 40/248 Connectivity information update
• CPC Class Codes: H04W 48/12 using downlink control channel
• CPC Class Codes: H04W 56/00 Synchronisation arrangements
• CPC Class Codes: H04W 56/0015 one node acting as a reference for the others
• CPC Class Codes: H04W 56/002 Mutual synchronization
• CPC Class Codes: H04W 8/005 Discovery of network devices, e.g. terminals
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks
• CPC Class Codes: H10N 70/8418 adapted for focusing electric field or current, e.g. tip-shaped
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/30 Smart metering, e.g. specially adapted for remote reading

Abstract

The present technology relates to protocols relative to utility meters associated with an open operational framework. More particularly, the present subject matter relates to protocol subject matter for advanced metering infrastructure, adaptable to various international standards, while economically supporting a 2-way mesh network solution in a wireless environment, such as for operating in a residential electricity meter field. The present subject matter supports meters within an ANSI standard C12.22/C12.19 system while economically supporting a 2-way mesh network solution in a wireless environment, such as for operating in a residential electricity meter field, all to permit cell-based adaptive insertion of C12.22 meters within an open framework. Cell isolation is provided through methodology and apparatus subject matter relating to quasi-orthogonal sequences in a frequency hopping network.

Claims

1. An advanced metering system frequency hopping network, comprising:

a central facility; and

a plurality of end devices, at least some of which end devices comprise metrology devices, with said central facility and said plurality of end devices being configured for bi-directional communications therebetween, and with each end device being associated with one of a plurality of cells each having a unique cell identifier;

wherein each end device within a given cell is configured for synchronized communications with each other end device in the given cell;

wherein communications among adjacent cells is substantially isolated; and

wherein communications effected by one or more end devices within a given cell are effected using a hopping pattern formed from a nested combination of two sequences, including an inner sequence generated with Galois field arithmetic and an outer sequence generated using the unique cell identifier for the given cell as a seed.

2. An advanced metering system as in claim 1, wherein the hopping pattern is more

particularly formed by using the elements of the outer sequence to select a specific N-hop inner sequence, where integer N is the number of channels used by the advanced metering system frequency hopping network.

3. An advanced metering system as in claim 2, wherein the outer sequence (OHS) is formed by:

breaking up the cell identifier for the given cell into a plurality of parts; and

generating a sequence starting with elements corresponding to respective selected ones of the plurality of parts of the cell identifier and forming subsequent elements in the sequence by repeatedly adding a plurality of prior sequence elements together.

4. An advanced metering system as in claim 1, wherein the outer sequence (OHS) is constructed by breaking up the cell identifier for the given cell into at least two parts and combining the at least two parts in a Fibonacci sequence according to the following relationship:

OHS(0)=Cell Identifier(0)

OHS(1)=Cell Identifier(1);

OHS(n)=OHS(n−

1)+OHS(n−

2), n=2, 3, 4, . . . , M−

1;

where the integer M is the length of the outer sequence.

5. An advanced metering system as in claim 1, wherein the outer sequence (OHS) is constructed by breaking up the cell identifier into at least four parts and combining the at least four parts in a Tetranacci sequence according to the following relationship:

OHS(n)=Cell Identifier(n), n=0, 1, 2, 3

OHS(n)=OHS(n−

1)+OHS(n−

2)+OHS(n−

3)+OHS(n−

4), n=4, . . . , M−

1

where the integer M is the length of the outer sequence.

6. An advanced metering system as in claim 1, wherein the inner sequence is calculated iteratively with knowledge of a previous hop and hopping sequence number.

7. An advanced metering system as in claim 2, wherein the inner sequence is

generated with a Galois field of order p, where p is a prime number, and wherein the selected specific N-hop inner sequence is selected from a plurality of k different inner sequences, and wherein the k-th inner sequence (IHS) is generated by the k-th primitive element (α

) and can be expressed as;

IHS(k)=(1,α

_k,α

_k²,α

_k³, . . . α

_k<sup>N−

1</sup>).

8. An advanced metering system as in claim 3, wherein the inner sequence (IHS) can be expressed as

IHS(k,n)=α

_kⁿ, k=0, 1, 2, . . . K−

1, n=0, 1, 2, . . . N−

1, where

IHS(k,n) is the channel number of the n-th hop of the k-th inner sequence and α

_k is the primitive element of the k-th inner sequence, and wherein the hopping pattern can be expressed as the following nested combination of inner and outer sequences;

{[IHS(OHS(0),0),IHS(OHS(0),1), . . . , IHS(OHS(0),N−

1)],

[IHS(OHS(1),0),IHS(OHS(1),1), . . . , IHS(OHS(1),N−

1)],

. . .

[IHS(OHS(M−

1),0),IHS(OHS(M−

1),1), . . . , IHS(OHS(M−

1),N−

1)]}.

9. A metrology device for use with an advanced metering system frequency hopping network, said metrology device characterized by a unique identifier, said metrology device comprising:

a metrology portion configured to measure consumption of a utility commodity;

a transmitter portion configured to transmit consumption information;

a receiver portion configured to receive information from other network devices; and

wherein said transmitter portion and said receiver portion are configured to communicate using a frequency hopping pattern formed from a nested combination of two sequences, including an inner hopping sequence generated with Galois field arithmetic and an outer hopping sequence generated using the unique identifier for the metrology device as a seed.

10. A metrology device as in claim 9, wherein the hopping pattern is more

particularly formed by using the elements of the outer hopping sequence to select a specific N-hop inner hopping sequence, where integer N is the number of channels used by the advanced metering system frequency hopping network.

11. A metrology device as in claim 10, wherein the outer hopping sequence (OHS) is formed by:

breaking up the unique identifier into a plurality of parts; and

generating a sequence starting with elements corresponding to respective selected ones of the plurality of parts of the unique identifier and forming subsequent elements in the sequence by repeatedly adding a plurality of prior sequence elements together.

12. A metrology device as in claim 9, wherein the outer hopping sequence (OHS) is

constructed by breaking up the unique identifier into at least two parts and combining the at least two parts in a Fibonacci sequence according to the following relationship:

OHS(0)=Cell Identifier(0)

OHS(1)=Cell Identifier(1);

OHS(n)=OHS(n−

1)+OHS(n−

2), n=2, 3, 4, . . . , M−

1;

where the integer M is the length of the outer hopping sequence.

13. A metrology device as in claim 9, wherein the outer hopping sequence (OHS) is

constructed by breaking up the unique identifier into at least four parts and combining the at least four parts in a Tetranacci sequence according to the following relationship:

OHS(n)=Cell Identifier(n), n=0, 1, 2, 3

OHS(n)=OHS(n−

1)+OHS(n−

2)+OHS(n−

3)+OHS(n−

4), n=4, . . . , M−

1

where the integer M is the length of the outer hopping sequence.

14. A metrology device as in claim 9, wherein the inner hopping sequence is calculated iteratively with knowledge of a previous hop and hopping sequence number.

15. A metrology device as in claim 10, wherein the inner hopping sequence is

generated with a Galois field of order p, where p is a prime number, and wherein the selected specific N-hop inner hopping sequence is selected from a plurality of k different inner hopping sequences, and wherein the k-th inner hopping sequence (IHS) is generated by the k-th primitive element (α

) and can be expressed as;

IHS(k)=(1,α

_k,α

_k²,α

_k³, . . . α

_k<sup>N−

1</sup>).

16. A metrology device as in claim 10, wherein the inner hopping sequence (IHS) can be expressed as IHS(k,n)=α

_kⁿ, k=0, 1, 2, . . . K−

1, n=0, 1, 2, . . . N−

1,where IHS(k,n) is the channel number of the n-th hop of the k-th inner hopping sequence and α

_k is the primitive element of the k-th inner hopping sequence, and wherein the hopping pattern can be expressed as the following nested combination of inner and outer hopping sequences;

{[IHS(OHS(0),0),IHS(OHS(0),1), . . . , IHS(OHS(0),N−

1)],

[IHS(OHS(1),0),IHS(OHS(1),1), . . . , IHS(OHS(1),N−

1)],

. . .

[IHS(OHS(M−

1),0),IHS(OHS(M−

1),1), . . . , IHS(OHS(M−

1),N−

1)]}.