MONITORING OF CHANNEL STABILITY AND INTERFERENCE IN WIRELESS NETWORKS

• US 20180160321A1
• Filed: 02/01/2018
• Published: 06/07/2018
• Est. Priority Date: 04/19/2013
• Status: Active Grant

• Current Assignee: Analog Devices International Unlimited Company (Analog Devices, Inc.)
• Original Assignee: Linear Technology Corporation (Analog Devices, Inc.)
• Inventors: DOHERTY, Lance Robert, LINDSAY, William Alan, SIMON, Jonathan Noah, LEVESQUE, Alain Pierre
• Granted Patent: US 10,595,216 B2
• Time in Patent Office: Days
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 24/04 Arrangements for maintaining operational condition
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

The stability of a channel in a wireless network is evaluated at a node. Upon transmitting a packet from the node on a network channel, a first counter associated with the channel is incremented. Upon receiving an acknowledgment packet responsive to the transmitted packet, a second counter associated with the channel is incremented. A stability metric for the channel is computed based on values stored in the first and second counters. Additionally, interference on a channel of the network is measured at a node. Upon determining that no packet is received during a predetermined time-period on the channel, a received signal strength (RSS) is measured on the channel at an end of the predetermined time-period. Alternatively, upon determining that a packet is received during the predetermined time-period on the channel, the RSS is measured on the channel following completion of the transmission of the packet on the channel.

Claims

1. A method for evaluating stability of communication channels in a wireless communication network, the method comprising steps of:

monitoring, by a first node of the wireless communication network, a plurality of communication channels utilized for communications between the first node and other nodes in the wireless communication network;

computing, by the first node, channel stability metrics for each of the plurality of communication channels; and

initiating, by the first node, in coordination with at least another node of the wireless communication network, a change in a usage of a selected communication channel of the plurality of communication channels based on the computed channel stability metrics for each of the plurality of communication channels.

2. The method of claim 1, wherein the initiating the change in the usage of the selected communication channel comprises:

discontinuing transmission of packets by the first node on the selected communication channel of the wireless communication network.

3. The method of claim 1, wherein the initiating the change in the usage of the selected communication channel comprises:

transmitting a reporting packet by the first node to at least one neighbor node of the first node in the wireless communication network, to cause the at least one neighbor node to stop transmitting packets to the first node on the selected communication channel of the wireless communication network.

4. The method of claim 1, wherein the initiating the change in the usage of the selected communication channel comprises:

transmitting a reporting packet, including the computed stability metric, from the first node to a manager of the wireless communication network; and

receiving at the first node, from the manager of the wireless communication network, a control packet for causing the first node to adjust a communication parameter,

wherein the adjustment to the communication parameter includes one of adjusting a superframe structure of the wireless communication network and adjusting a routing graph of the wireless communication network to discontinue the usage of the selected communication channel.

5. The method of claim 1, wherein the computed channel stability metrics include a rate at which packets are successfully communicated to or from the first node on each of the plurality of communication channels, and

the method further comprises discontinuing usage of the selected communication channel subject when the selected communication channel has a low rate at which packets are successfully communicated to or from the first node.

6. The method of claim 1, further comprising:

incrementing, by the first node, a first transmit counter of a plurality of transmit counters in response to a first packet being transmitted from the first node to a second node of the wireless communication network using a first communication channel of the plurality of communication channels, each of the plurality of transmit counters being associated with a different communication channel of the plurality of communication channels and the first transmit counter being associated with the first communication channel;

in response to receiving an acknowledgement that the first packet was received by the second node, determining a second communication channel of the wireless communication network associated with the second packet and incrementing a second receive counter of a plurality of receive counters, each of the plurality of receive counters being associated with a different communication channel of the plurality of communication channels and the second receive counter being associated with the second communication channel; and

computing the channel stability metric for the first communication channel of the wireless communication network based on incremented values stored in the transmit and receive counters.

7. The method of claim 6, wherein the second channel of the wireless communication network associated with the second packet is a channel that the second packet is received on.

8. The method of claim 6, wherein the second channel of the wireless communication network associated with the second packet is a same channel as the first communication channel on which the first packet is transmitted.

9. The method of claim 6, wherein the second packet is one of an acknowledgment (ACK) or a negative acknowledgment (NACK) packet.

10. The method of claim 6, further comprising:

determining whether the first packet transmitted to the second node of the wireless communication network is of a type of packet whose receipt is acknowledged,

wherein the first transmit counter is incremented only upon determining that the first packet is of a type of packet whose receipt is acknowledged.

11. The method of claim 6, wherein the second receive counter is incremented only when the second packet is received.

12. The method of claim 1, wherein each communication channel corresponds to a different frequency band used for communication in the wireless communication network.

13. The method of claim 1, wherein the first node is configured to transmit packets to multiple different other nodes of the wireless communication network on a particular communication channel of the plurality of communication channels of the wireless communication network.

14. The method of claim 1, wherein the first node is configured to transmit packets to a second node of the wireless communication network on multiple different communication channels of the plurality of communication channels of the wireless communication network.

15. A wireless network node in communication with other wireless network nodes across a wireless communication network, the wireless network node comprising:

a transceiver configured to transmit and receive packets on selected communication channels of a plurality of communication channels of the wireless communication network; and

a processor configured to control operation of the transceiver to monitor the plurality of communication channels and to compute, for each respective communication channel of the plurality of communication channels, a channel stability metric for the respective communication channel,

wherein the processor is further configured to initiate, in coordination with at least another node of the wireless communication network, a change in a usage of a selected communication channel of the plurality of communication channels based on the computed channel stability metrics for each of the plurality of communication channels.

16. The wireless network node of claim 15, wherein the processor is configured to initiate the change in the usage of the selected communication channel by discontinuing transmission of packets on the selected communication channel of the wireless communication network.

17. The wireless network node of claim 15, wherein the processor is configured to initiate the change in the usage of the selected communication channel by causing the transceiver to transmit a reporting packet to at least one neighbor node of the first node in the wireless communication network to cause the at least one neighbor node to stop transmitting packets to the first node on the selected communication channel of the wireless communication network.

18. The wireless network node of claim 15, wherein the processor is configured to initiate the change in the usage of the selected communication channel by:

causing the transceiver to transmit a reporting packet, including the computed stability metric to a manager of the wireless communication network; and

receiving through the transceiver from the manager of the wireless communication network, a control packet for causing the wireless network node to adjust a communication parameter,

wherein the adjustment to the communication parameter includes one of adjusting a superframe structure of the wireless communication network and adjusting a routing graph of the wireless communication network to discontinue the usage of the selected communication channel.

19. The wireless network node of claim 15, wherein each communication channel corresponds to a different frequency band used for communication in the wireless communication network, and the transceiver is configured to transmit and receive packets on any selected frequency band of a plurality of frequency bands of the wireless communication network.

20. A wireless network node configured for communication with other wireless network nodes of a wireless communication network across a plurality of communication channels, the wireless network node comprising:

means for monitoring the plurality of communication channels utilized for communications between the wireless network node and the other wireless network nodes in the wireless communication network;

means for computing channel stability metrics for each of the plurality of communication channels; and

means for initiating_;

in coordination with at least another node of the wireless communication network, a change in a usage of a selected communication channel of the plurality of communication channels based on the computed channel stability metrics for each of the plurality of communication channels.