Adapting channel width for improving the performance of wireless networks

• US 8,699,424 B2
• Filed: 06/27/2008
• Issued: 04/15/2014
• Est. Priority Date: 06/27/2008
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Chandra, Ranveer, Mahajan, Ratul, Moscibroda, Thomas, Bahl, Paramvir, Raghavendra, Ramya
• Primary Examiner(s): Hamza, Faruk
• Assistant Examiner(s): LO, DIANE LEE
• Application Number:
  US12/163,187
• Publication Number:
  US 20090323600A1
• Time in Patent Office: 2,118 Days
• Field of Search: 370/329, 370/437
• US Class Current: 370/329
• CPC Class Codes: H04W 24/02 Arrangements for optimising operational condition
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 28/20 Negotiating bandwidth

Abstract

The subject invention relates to a system and/or methodology that provide improved wireless networking performance by dynamically adapting the channel width. A dynamic adaptation component adjust the channel width based on at least one characteristic of a wireless network, the characteristics can include but are not limited to range, power consumption, throughput, signal to noise ratio (SNR), resilience to delay spread, data rate, and capacity. Additionally, an optimization component can determine an optimum channel width.

Claims

1. A system comprising:

a wireless transmitter that sends one or more symbols in a wireless signal via a channel having a specified width;

a sensing and analysis component that determines a value for at least one attribute of at least one of;

the wireless signal, or the wireless transmitter;

and

a dynamic adaptation component that adjusts the channel width based at least in part on;

a determination of a parameter pair that includes a first threshold value and a second threshold value, the first threshold value and the second threshold value comprising average data rates corresponding to a maximum data throughput efficiency of the channel, the determination of the parameter pair being based at least in part on a number of probing intervals between probes of the channel;

a determination of a current average data rate for the channel at the specified width; and

a determination of a relationship between the current average data rate and the parameter pair, the channel width being adjusted based at least in part on the relationship.

2. The system of claim 1, wherein the attribute includes at least one of energy consumption, data rate, loss rate, interference, link condition, signal-to-noise ratio (SNR), or signal strength.

3. The system of claim 1, wherein the channel having a first bandwidth hosting a plurality of flows is partitioned into a plurality of channels having a second bandwidth in order to increase capacity or decrease interference, and the second bandwidth for each flow being narrower than the first bandwidth.

4. The system of claim 1, wherein:

the channel width initially corresponds to a preset channel width, and

the dynamic adaptation component adjusts the preset channel width.

5. The system of claim 1, wherein the dynamic adaptation component further comprises a binding component that maintains networking associations when the dynamic adaptation component adjusts the channel width.

6. The system of claim 1, further comprising a control component that obtains at least one desired optimization objective.

7. The system of claim 6, wherein the desired optimization objective includes at least one of throughput, transmission range, capacity, or energy consumption.

8. The system of claim 6, wherein the dynamic adaptation component further comprises an optimization component that determines an optimum channel width for the wireless transmitter based at least in part on at least one of the attribute or the desired optimization objective.

9. The system of claim 8, wherein the optimum channel width is at least one of:

a channel width having a greatest throughput, a channel width having a most efficient energy consumption, a channel width with a least energy-per-byte, or a channel width with a longest transmission range.

10. The system of claim 8, wherein the optimization component further comprises a probing component that samples other channel widths to determine the optimum channel width.

11. The system of claim 6, wherein the control component obtains the at least one desired optimization objective from at least one of:

a policy, a user, an application, or a higher-layer protocol.

12. The system of claim 6, wherein:

if the current average data rate is below the first threshold value, the channel width is adjusted from the specified width to an adjacent narrower channel width of a set of known channel widths;

if the current average data rate is above the second threshold value, the channel width is adjusted from the specified width to an adjacent wider channel width of the set of known channel widths; and

if the current average data rate is between the first threshold value and the second threshold value or if the current average data rate is equal to the first threshold value or the second threshold value, the channel width is adjusted according to the highest measured throughput or the highest measured energy efficiency of the channel based on at least one of the attribute or the desired optimization objective.

13. A method comprising:

transmitting one or more symbols in a wireless signal via a channel having a specified width;

determining at least one value for at least one characteristic of at least one of the wireless signal, or a wireless signal transmitter;

obtaining at least one optimization objective; and

adjusting the channel width based at least in part on;

determining a parameter pair that includes a first threshold value and a second threshold value, the first threshold value and the second threshold value comprising average data rates corresponding to a maximum data throughput efficiency of the channel, the determining the parameter pair being based at least in part on a number of probing intervals between probes of the channel;

determining a current average data rate for the channel at the specified width;

determining a relationship between the current average data rate and the parameter pair, the channel width being adjusted based at least in part on the relationship and at least one of the characteristic or the optimization objective.

14. The method of claim 13, wherein at least one of the characteristic or the optimization objective includes at least one of energy consumption, data rate, loss rate, interference, link condition, signal-to-noise ratio (SNR), signal strength, throughput, transmission range, or capacity.

15. The method of claim 13, further comprising determining an optimum channel width for the wireless signal transmitter based at least in part on at least one of the characteristic or the optimization objective,

wherein the optimum channel width is at least one of:

a channel width having a greatest throughput, a channel width having a most efficient energy consumption, a channel width having a least energy per byte, or a channel width having a longest transmission range.

16. The method of claim 15, further comprising sampling other channel widths to determine the optimum channel width.

17. The method of claim 13, further comprising implementing adaptive channel width control using wireless transmitters by at least one of:

maintaining one or more rate tables that are loaded by a device driver of the wireless signal transmitter, modifying a slot time to be the same across all channel widths, or adjusting a computation for packet durations according to different channel widths.

18. The method of claim 13, further comprising splitting the channel having a first bandwidth hosting multiple conversations into a plurality of channels having a bandwidth that is narrower than the first bandwidth, wherein there is one or more conversations per channel.

19. The method of claim 13, further comprising maintaining a data rate supported by the channel width when the channel width of the wireless signal transmitter is adjusted.

20. The method of claim 13, wherein the optimization objective is obtained from at least one of:

a policy, a user, an application, or a higher-layer protocol.

21. The method of claim 13, further comprising selecting the narrowest available channel width when there is no data to transmit.

22. A method comprising:

transmitting a wireless signal by a wireless transmitter via a channel having a specified channel width;

determining at least one characteristic of at least one of the wireless signal, or the wireless transmitter, the characteristic including at least one of energy consumption, data rate, loss rate, interference, link condition, signal-to-noise ratio (SNR), or signal strength;

acquiring at least one network objective from at least one of a policy, a user, an application, or a higher-layer protocol, the network objective including at least one of throughput, transmission range, capacity, or power consumption; and

adjusting the channel width based at least in part on;

determining a parameter pair that includes a first threshold value and a second threshold value, the first threshold value and the second threshold value comprising average data rates corresponding to a maximum data throughput efficiency of the channel, the determining the parameter pair being based at least in part on a number of probing intervals between probes of the channel;

determining a current average data rate for the channel at the specified channel width relative to the first threshold value and the second threshold value, wherein;

if the current average data rate is below the first threshold value and the channel has not been probed within the number of probing intervals, the channel width is adjusted from the specified channel width to an adjacent narrower channel width of a set of predetermined channel widths;

if the current average data rate is above the second threshold value and the channel has not been probed within the number of probing intervals, the channel width is adjusted from the specified channel width to an adjacent wider channel width of the set of predetermined channel widths; and

if the current average data rate is between the first threshold value and the second threshold value or if the current average data rate is equal to the first threshold value or the second threshold value, the channel width is adjusted according to a highest measured throughput or a highest measured energy efficiency of the channel based on at least one of the characteristic or the network objective.