Method and Apparatus for Determining the Locating of Nodes in a Wireless Network

• US 20080240116A1
• Filed: 03/26/2007
• Published: 10/02/2008
• Est. Priority Date: 03/26/2007
• Status: Abandoned Application

• Current Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Original Assignee: Motorola, Inc. (Motorola Solutions, Inc.)
• Inventors: O'Dea, Robert J., Niu, Feng, Bancroft, Timothy J.
• Application Number:
  US11/691,066
• Publication Number:
  US 20080240116A1
• Time in Patent Office: Days
• US Class Current: 370/400
• CPC Class Codes: H04W 40/246 Connectivity information discovery
• CPC Class Codes: H04W 64/00 Locating users or terminals or network equipment for network management purposes, e.g. mobility management
• 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

Abstract

A method and apparatus for determining the relative locations of nodes in a wireless network is disclosed. A list of neighboring nodes of a master node of the wireless network is generated and, from this list, a list of independent nodes is generated. An adjacency table for the independent nodes is then generated by examining the neighbors of dependent nodes. Two independent nodes are determined to be adjacent nodes only if they are the only neighboring nodes of a dependent node. Relative locations of nodes in wireless network may be determined from the adjacency table.

Claims

1. A method for determining relative locations of nodes in wireless network, the method comprising:

generating a list of neighboring nodes of a master node of the wireless network;

generating, from the list of neighboring nodes, a list of independent nodes;

for each selected node of the list of neighboring nodes that is not an independent node;

determining two independent nodes to be adjacent nodes if only if they are the only neighboring nodes of the selected node;

generating an adjacency table for the independent nodes; and

determining relative locations of nodes in wireless network from the adjacency table.

2. A method in accordance with claim 1, wherein generating the list of independent nodes comprises:

generating a ranking list of nodes in the list of neighboring nodes; and

for each successively selected node in the ranking list;

determining the selected node to be an independent node if no other independent node is a neighbor of the selected node.

3. A method in accordance with claim 2, wherein generating a ranking list of nodes in the list of neighboring nodes comprises:

for each selected node of the list of neighboring nodes of the master node;

determining the number of nodes that are neighbors of both the selected node and the master node; and

ranking the list of nodes in the list of neighboring nodes in accordance to the number of nodes that are neighbors of both the selected node and the master node, wherein a node having the smallest number of nodes that are neighbors of both the selected node and the master node is positioned first in the ranking list.

4. A method in accordance with claim 2, wherein generating a ranking list of nodes in the list of neighboring nodes comprises:

for each selected node of the list of neighboring nodes of the master node;

determining the path loss between the selected node and the master node; and

ranking the list of nodes in the list of neighboring nodes in accordance to the path loss between the selected node and the master node,

wherein a node having the largest path loss is positioned first in the ranking list.

5. A method for determining relative locations of nodes in wireless network, the method comprising:

generating a list of neighboring nodes of a master node of the wireless network;

generating, from the list of neighboring nodes, a list of independent nodes;

a first neighboring node of the master node determining its relative location by determining which independent nodes are neighboring nodes.

6. A method in accordance claim 5, wherein generating a list of neighboring nodes of the master node of the wireless network and generating, from the list of neighboring nodes, a list of independent nodes is performed by the master node, the method further comprising:

the master node transmitting the list of independent node to the first neighboring node.

7. A method in accordance with claim 5, wherein generating the list of independent nodes comprises:

generating a ranking list of nodes in the list of neighboring nodes; and

for each successively selected node in the ranking list;

determining the selected node to be an independent node if no independent node is a neighbor of the selected node.

8. A method in accordance with claim 7, wherein generating a ranking list of nodes in the list of neighboring nodes comprises:

for each selected node of the list of neighboring nodes of the master node;

determining the number of nodes that are neighbors of both the selected node and the master node; and

ranking the list of nodes in the list of neighboring nodes in accordance to the number of nodes that are neighbors of both the selected node and the master node, wherein a node having the smallest number of nodes that are neighbors of both the selected node and the master node is positioned first in the ranking list.

9. A method in accordance with claim 7, wherein generating a ranking list of nodes in the list of neighboring nodes comprises:

for each selected node of the list of neighboring nodes of the master node;

determining the path loss between the selected node and the master node; and

ranking the list of nodes in the list of neighboring nodes in accordance to the path loss between the selected node and the master node,

wherein a node having the largest path loss is positioned first in the ranking list.

10. A wireless network comprising:

a master node;

a set of neighboring nodes, operable to communicate with the master node;

wherein the master node is operable to;

select, from the set of neighboring nodes, a set of independent nodes, where no independent node is a neighbor of any other independent node;

determine which nodes of the set of independent nodes are adjacent to one another; and

determine the relative location a selected node of the set of neighboring nodes by determining which independent nodes are neighbors of the selected node.

11. A wireless network in accordance with claim 10, wherein the wireless network comprises a piconet.

12. A wireless network in accordance with claim 10, wherein the master mode is further operable to select the set of independent nodes by:

generating a ranking list of neighboring nodes; and

for each successively selected node in the ranking list;

determining the selected node to be an independent node if no other independent node is a neighbor of the selected node.

13. A wireless network in accordance with claim 12, wherein the master node is further operable to determine the path loss between the master node and each neighboring node, wherein the nodes in the ranking list are ordered dependent upon the path loss.

14. A wireless network in accordance with claim 12, wherein the master node is further operable to determine the number of neighbors it has in common with each neighboring node, wherein the nodes in the ranking list are ordered dependent upon the number of common neighbors.

15. A wireless network comprising:

a master node;

a set of neighboring nodes, operable to communicate with the master node;

wherein the master node is operable to;

select, from the set of neighboring nodes, a set of independent nodes, where no independent node is a neighbor of any other independent node;

determine which nodes of the set of independent nodes are adjacent to one another; and

wherein a node of the set of neighboring nodes is further operable to determine its relative location in the network by determining which independent nodes are its neighbors.

16. A wireless network in accordance with claim 15, wherein the wireless network comprises a piconet.

17. A wireless network in accordance with claim 15, wherein the master mode is further operable to select the set of independent nodes by:

generating a ranking list of neighboring nodes; and

for each successively selected node in the ranking list;

determining the selected node to be an independent node if no other independent node is a neighbor of the selected node.

18. A wireless network in accordance with claim 17, wherein the master node is further operable to determine the path loss between the master node and each neighboring node, wherein the nodes in the ranking list are ordered dependent upon the path loss.

19. A wireless network in accordance with claim 17, wherein the master node is further operable to determine the number of neighbors it has in common with each neighboring node, and wherein the nodes in the ranking list are ordered dependent upon the number of common neighbors.