Use of minimal propagation delay path to optimize a mesh network
View Patent ↗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. Particular present features relate to the use of minimal propagation delay path to optimize a mesh network.
1. A method for optimizing an advanced metering system mesh network, comprising:
establishing a network including a central facility root node and a plurality of node devices, and at least some of the node devices comprise metrology devices;
configuring the network for bi-directional communications between the central facility root node and each of the plurality of node devices;
computing total propagation delay along each path to the central facility root node;
selecting at each node device the lowest value of total propagation delay to define its own global propagation delay value;
sharing the global propagation delay valve for each node device with every other node device accessible within its range;
calculating a global propagation delay to the central facility root node for each respective node device using only local propagation delay for each respective node device and shared values from its immediate neighbors; and
conducting communications using the path corresponding to the selected value,
whereby communications among nodes within the network is optimized.
2. A method as in claim 1 , wherein each node device shares its own global propagation delay value by updating its message header.
3. A method as in claim 1 , wherein average local propagation delay is derived by:
maintaining a record of all communication attempts with each one of the plurality of node devices in the direction of the central facility root node; and
computing a statistical communication success rate for each one of the plurality of node devices.
4. A method as in claim 1 , further including computing average local propagation delay for each one-hop link using the relationship:
D
=
T
d
+
T
r
(
1
-
P
P
)
where D is the average local propagation delay, T d is time needed by a packet to travel from a transmitter to a receiver, P is packet success rate, and T r is wait time between transmissions.
5. A method as in claim 4 , wherein the average local propagation delay is updated after each use of any given link.
6. A method as in claim 4 , wherein the packet success rate is updated after each packet transmission attempt with a sliding average using the relationship:
P
(
n
)
=
PS
(
n
)
N
av
+
N
av
-
1
N
av
P
(
n
-
1
)
where P(n) is the packet success rate for a given node n, N av is the number of transmissions used to compute the average, and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.
7. A method as in claim 6 , wherein the propagation delay of any link is updated using the relationship:
D
r
(
n
)
=
{
N
av
D
r
(
n
-
1
)
+
1
N
av
-
1
if
PS
(
n
)
=
0
(
N
av
-
1
)
D
r
(
n
-
1
)
D
r
(
n
-
1
)
+
N
av
if
PS
(
n
)
=
1
where D r (n) is the propagation delay of a link for transmission n and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.
8. A method for optimizing an advanced metering system mesh network, comprising:
establishing a network including a central facility root node and a plurality of node devices, at least some of the node devices comprise metrology devices;
configuring the network for bi-directional communications between the central facility root node and each of the plurality of node devices;
propagating global propagation delay information from the central facility root node to each of the node devices on a step by step basis;
storing global propagation delay information at each node device; and
conducting communications using a path corresponding to the lowest value of total propagation delay based on the stored global propagation delay information and average local propagation delay,
whereby each node device selects a communications path based only on knowledge of its own average local propagation delay and the global propagation delay information from immediate neighbor node devices.
9. A method as in claim 8 , wherein each node makes available its own global propagation delay value by updating its message header.
10. A method as in claim 8 , wherein the average local propagation delay is derived by:
maintaining a record of all communication attempts with each one of the plurality of node devices in the direction of the central facility root node; and
computing a statistical communication success rate for each one of the plurality of node devices.
11. A method as in claim 8 , further including computing average local propagation delay for each one-hop link using the relationship:
D
=
T
d
+
T
r
(
1
-
P
P
)
where D is the average local propagation delay, T d is time needed by a packet to travel from a transmitter to a receiver, P is packet success rate, and T r is wait time between transmissions.
12. A method as in claim 11 , wherein the average local propagation delay is updated after each use of any given link.
13. A method as in claim 11 , wherein the packet success rate is updated after each packet transmission attempt with a sliding average using the relationship:
P
(
n
)
=
PS
(
n
)
N
av
+
N
av
-
1
N
av
P
(
n
-
1
)
where P(n) is the packet success rate for a given node n, N av is the number of transmissions used to compute the average, and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.
14. A method as in claim 13 , wherein the propagation delay of any link is updated using the relationship:
D
r
(
n
)
=
{
N
av
D
r
(
n
-
1
)
+
1
N
av
-
1
if
PS
(
n
)
=
0
(
N
av
-
1
)
D
r
(
n
-
1
)
D
r
(
n
-
1
)
+
N
av
if
PS
(
n
)
=
1
where D r (n) is the propagation delay of a link for transmission n and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.
15. An advanced metering system mesh network, comprising;
a central facility root node; and
a plurality of node devices, each node device configured for bi-directional communications with said central facility root node, and at least some of the node devices comprise metrology devices;
wherein each node device is further configured to compute an average propagation delay for each one-hop link to itself in the mesh network and to select the shortest transmission path to said central facility root node based only on its own computed average propagation delay and global propagation delay information stored in its immediate neighbors;
whereby communications between said central facility root node and said plurality of node devices are optimized.
16. An advanced metering system mesh network as in claim 15 , wherein said central facility root node is configured to propagate global propagation delay information to each node device on a step by step basis.
17. An advanced metering system mesh network as in claim 15 , wherein each node device is configured to calculate its own average local propagation delay by maintaining a record of all communication attempts with each one of the plurality of node devices in the direction of said central facility root node and computing a statistical communication success rate for each one of said plurality of node devices.
18. An advanced metering system mesh network as in claim 15 , wherein each node device is configured to compute its average local propagation delay for each one-hop link using the relationship:
D
=
T
d
+
T
r
(
1
-
P
P
)
where D is the average local propagation delay, T d is time needed by a packet to travel from a transmitter to a receiver, P is packet success rate, and T r is wait time between transmissions.
19. An advanced metering system mesh network as in claim 18 , wherein each node device is configured to update its average local propagation delay calculation after each use of any given link.
20. An advanced metering system mesh network as in claim 18 , wherein each node device is configured to update its packet success rate after each packet transmission attempt with a sliding average using the relationship:
P
(
n
)
=
PS
(
n
)
N
av
+
N
av
-
1
N
av
P
(
n
-
1
)
where P(n) is the packet success rate for a given node n, N av is the number of transmissions used to compute the average, and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.
21. An advanced metering system mesh network as in claim 20 , wherein each node device is configured to update the propagation delay to any other linked node device using the relationship:
D
r
(
n
)
=
{
N
av
D
r
(
n
-
1
)
+
1
N
av
-
1
if
PS
(
n
)
=
0
(
N
av
-
1
)
D
r
(
n
-
1
)
D
r
(
n
-
1
)
+
N
av
if
PS
(
n
)
=
1
where D r (n) is the propagation delay of a link for transmission n and PS(n) is an indication of success or failure at attempt n where PS(n)=0 if transmission n failed and PS(n)=1 if transmission n succeeded.