Channel hopping sequence generation with variable channel width

• US 10,595,300 B2
• Filed: 06/15/2018
• Issued: 03/17/2020
• Est. Priority Date: 06/15/2018
• Status: Active Grant

• Current Assignee: Landis+Gyr Technology, Inc. (Landis+Gyr Group AG)
• Original Assignee: Landis+Gyr Innovations Incorporated (Landis+Gyr Group AG)
• Inventors: Matthews, Justin Clifford, Karlgaard, Matthew Donald, Kharangate, Govind, Holcombe, Michael Sean
• Primary Examiner(s): Moore, Jr., Michael J
• Application Number:
  US16/009,930
• Publication Number:
  US 20190387499A1
• Time in Patent Office: 641 Days
• CPC Class Codes: H04B 1/713 using frequency hopping
• CPC Class Codes: H04B 1/7136 Arrangements for generation of hop frequencies, e.g. using a bank of frequency sources, using continuous tuning or using a transform
• CPC Class Codes: H04B 2201/71384 Look-up tables
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0446 Resources in time domain, e.g. slots or frames
• CPC Class Codes: H04W 72/542 using measured or perceived quality
• CPC Class Codes: H04W 84/18 Self-organising networks, e.g. ad-hoc networks or sensor networks

Abstract

In some aspects, a channel hopping sequence for communication on a mesh network is generated. The hopping sequence may include multiple channels assigned to respective positions in the hopping sequence. In some cases, a first channel is assigned to a first position such that the first channel may transmit communications in a first transmission mode, such as a low-bandwidth transmission mode. In addition, an additional channels adjacent to the first channel is also assigned to the first position such that the combination of the first channel and additional channel may transmit communications in a second transmission mode, such as a high-bandwidth transmission mode. In some cases, a whitelist is determined based on the assigned channels. The whitelist may indicate channels that do not conflict with the assigned channels during transmission of a communication. In addition, channels may be assigned to the hopping sequence based on the whitelist.

Claims

1. A method of generating a channel hopping sequence for communicating across a wireless mesh network, the method comprising:

receiving an indication of a group of channels, each channel including a respective frequency range for communicating on the wireless mesh network and available for use in the channel hopping sequence, wherein the channel hopping sequence defines an ordered sequence of channel numbers spanning multiple time slots;

receiving, from a pseudo-random number generator, an indication of a first number;

assigning a first channel, from the group of channels, to the channel hopping sequence at a first position in the channel hopping sequence, based on the first number;

selecting an additional channel, from the group of channels, wherein the additional channel is adjacent to the first channel,

wherein frequencies included in a first width of the first channel are available at a first time slot for a first transmission mode,

wherein frequencies included in a combined width of the first channel and the additional channel are available at the first time slot for a second transmission mode;

determining a whitelist subset of the group of channels, wherein the whitelist subset omits the first channel and the additional channel; and

assigning a second channel, from the whitelist subset, to the channel hopping sequence at a second position in the channel hopping sequence, based on a second number received from the pseudo-random number generator.

2. The method of claim 1, further comprising determining a blacklist subset of the group of channels, wherein the blacklist subset includes the first channel and the additional channel, wherein:

the blacklist subset indicates that the first channel is unavailable for a first quantity of time slots that is based on a maximum transmission time of the first transmission mode, and

the blacklist subset indicates that the additional channel is unavailable for an additional quantity of time slots that is based on a maximum transmission time of the second transmission mode.

3. The method of claim 1, further comprising:

calculating a reserved time duration of the first channel, wherein the reserved time duration is based on a sum of the first time slot and a quantity of time slots associated with a maximum transmission time of the first transmission mode;

assigning a third channel, from the group of channels, to the channel hopping sequence at a third position, based on a third number received from the pseudo-random number generator, wherein the third position is associated with a third time slot;

based on a comparison of the reserved time duration and the third time slot, determining that the third time slot is subsequent to the reserved time duration; and

responsive to determining that the third time slot is subsequent to the reserved time duration, updating the whitelist subset to include the first channel.

4. The method of claim 3, further comprising:

calculating an additional reserved time duration of the additional channel, wherein the additional reserved time duration is based on an additional sum of the first time slot and an additional quantity of time slots associated with an additional maximum transmission time of the second transmission mode; and

responsive to determining that the third time slot is subsequent to the additional reserved time duration, updating the whitelist subset to include the additional channel.

5. The method of claim 1, wherein a communication that is transmitted via the second transmission mode is transmitted via a combination of frequencies included in the respective frequency ranges of the first channel and the additional channel.

6. The method of claim 1, wherein:

the first transmission mode is a low-bandwidth transmission mode, and

the second transmission mode is a high-bandwidth transmission mode.

7. The method of claim 1, further comprising:

selecting another channel from the group of channels based on the first channel,

wherein frequencies included in a combined width of the first channel and at least the another channel are available at the first time slot for a third transmission mode,

wherein the whitelist subset further omits the another channel.

8. The method of claim 1, wherein a node device on the mesh network:

selects the first position in the channel hopping sequence for a communication with an additional node on the mesh network;

determines the first channel and the first time slot based on the first position in the channel hopping sequence;

determines a signal quality associated with the additional node; and

based on the signal quality, selects the first transmission mode or the second transmission mode for the communication,

wherein the first transmission mode is selected responsive to determining that the signal quality is below a threshold signal quality,

wherein the second transmission mode is selected responsive to determining that the signal quality is above the threshold signal quality.

9. A node capable of generating a channel hopping sequence for communicating on a wireless mesh network, the node comprising a processor configured with code to perform operations comprising:

receiving an indication of a group of channels, each channel including a respective frequency range for communicating on the wireless mesh network and available for use in the channel hopping sequence, wherein the channel hopping sequence defines an ordered sequence of channel numbers spanning multiple time slots;

receiving, from a pseudo-random number generator, an indication of a first number;

assigning a first channel, from the group of channels, to the channel hopping sequence at a first position in the channel hopping sequence, based on the first number;

selecting an additional channel, from the group of channels, wherein the additional channel is adjacent to the first channel,

wherein frequencies included in a first width of the first channel are available at a first time slot for a first transmission mode,

wherein frequencies included in a combined width of the first channel and the additional channel are available at the first time slot for a second transmission mode;

determining a whitelist subset of the group of channels, wherein the whitelist subset omits the first channel and the additional channel; and

assigning a second channel, from the whitelist subset, to the channel hopping sequence at a second position in the channel hopping sequence, based on a second number received from the pseudo-random number generator.

10. The node of claim 9, the operations further comprising:

calculating a reserved time duration of the first channel, wherein the reserved time duration is based on a sum of the first time slot and a quantity of time slots associated with a communication transmitted via the first channel;

assigning another channel, from the group of channels, to the channel hopping sequence at another position, based on another number received from the pseudo-random number generator, wherein the another position is associated with another time slot;

based on a comparison of the reserved time duration and the another time slot, determining that the another time slot is subsequent to the reserved time duration; and

responsive to determining that the another time slot is subsequent to the reserved time duration, updating the whitelist subset to include the first channel.

11. The node of claim 10, the operations further comprising:

calculating an additional reserved time duration of the additional channel, wherein the additional reserved time duration is based on an additional sum of the first time slot and an additional quantity of time slots associated with an additional maximum transmission time of the second transmission mode; and

responsive to determining that the another time slot is subsequent to the additional reserved time duration, updating the whitelist subset to include the additional channel.

12. The node of claim 9, wherein a communication that is transmitted via the second transmission mode is transmitted via a combination of frequencies included in the respective frequency ranges of the first channel and the additional channel.

13. The node of claim 9, the operations further comprising:

selecting the first position in the channel hopping sequence for a communication with an additional node on the mesh network;

determining the first channel and the first time slot based on the selected first position in the channel hopping sequence;

determining a signal quality associated with the additional node; and

based on the signal quality, selecting the first transmission mode or the second transmission mode for the communication,

wherein the first transmission mode is selected responsive to determining that the signal quality is below a threshold signal quality,

wherein the second transmission mode is selected responsive to determining that the signal quality is above the threshold signal quality.

14. The node of claim 13, wherein:

the first channel is associated with the first transmission mode and the additional channel is associated with the second transmission mode;

responsive to selecting the first transmission mode, the node transmits the communication via the respective frequency range included in the first channel; and

responsive to selecting the second transmission mode, the node transmits the communication via a combination of the respective frequency ranges of the first channel and the additional channel.

15. A wireless mesh network comprising multiple nodes,

wherein at least one node of the multiple nodes is capable of generating a channel hopping sequence, such that each of the multiple nodes communicates on the wireless mesh network according to the generated channel hopping sequence,

wherein the at least one node comprises a processor configured with code to perform operations comprising:

receiving an indication of a group of channels, each channel including a respective frequency range for communicating on the wireless mesh network and available for use in the channel hopping sequence, wherein the channel hopping sequence defines an ordered sequence of channel numbers spanning multiple time slots;

receiving, from a pseudo-random number generator, an indication of a first number;

assigning a first channel, from the group of channels, to the channel hopping sequence at a first position in the channel hopping sequence, based on the first number;

selecting an additional channel, from the group of channels, wherein the additional channel is adjacent to the first channel,

wherein frequencies included in a first width of the first channel are available at a first time slot for a first transmission mode,

wherein frequencies included in a combined width of the first channel and the additional channel are available at the first time slot for a second transmission mode;

determining a whitelist subset of the group of channels, wherein the whitelist subset omits the first channel and the additional channel; and

assigning a second channel, from the whitelist subset, to the channel hopping sequence at a second position in the channel hopping sequence, based on a second number received from the pseudo-random number generator.

16. The wireless mesh network of claim 15, the operations further comprising determining a blacklist subset of the group of channels, wherein the blacklist subset includes the first channel and the additional channel, wherein:

the blacklist subset indicates that the first channel is unavailable for a first quantity of time slots that is based on a maximum transmission time of the first transmission mode, and

the blacklist subset indicates that the additional channel is unavailable for an additional quantity of time slots that is based on a maximum transmission time of the second transmission mode.

17. The wireless mesh network of claim 15, the operations further comprising:

calculating a reserved time duration of the first channel, wherein the reserved time duration is based on a sum of the first time slot and a quantity of time slots associated with a communication transmitted via the first channel;

assigning another channel, from the group of channels, to the channel hopping sequence at another position, based on another number received from the pseudo-random number generator, wherein the another position is associated with another time slot;

based on a comparison of the reserved time duration and the another time slot, determining that the another time slot is subsequent to the reserved time duration; and

responsive to determining that the another time slot is subsequent to the reserved time duration, updating the whitelist subset to include the first channel.

18. The wireless mesh network of claim 15, wherein a communication that is transmitted via the second transmission mode is transmitted via a combination of frequencies included in the respective frequency ranges of the first channel and the additional channel.

19. The wireless mesh network of claim 15, wherein a particular node of the multiple nodes:

selects the first position in the channel hopping sequence for a communication with an additional one of the multiple nodes;

determines the first channel and the first time slot based on the first position in the channel hopping sequence;

determines a signal quality associated with the additional one of the multiple nodes; and

based on the signal quality, selects the first transmission mode or the second transmission mode for the communication,

wherein the first transmission mode is selected responsive to determining that the signal quality is below a threshold signal quality,

wherein the second transmission mode is selected responsive to determining that the signal quality is above the threshold signal quality.

20. The wireless mesh network of claim 19, wherein:

the first channel is associated with the first transmission mode and the additional channel is associated with the second transmission mode;

responsive to selecting the first transmission mode, the particular node transmits the communication via the respective frequency range included in the first channel; and

responsive to selecting the second transmission mode, the particular node transmits the communication via a combination of the respective frequency ranges of the first channel and the additional channel.