Opportunistic use of wireless network stations as repeaters

• US 8,050,212 B2
• Filed: 02/16/2007
• Issued: 11/01/2011
• Est. Priority Date: 05/02/2003
• Status: Expired due to Fees

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Corporation
• Inventors: Bahl, Paramvir, Yu, Yan, Chandra, Ranveer, Padhye, Jitendra D.
• Primary Examiner(s): Eng; George
• Assistant Examiner(s): HUYNH, NAM TRUNG
• Application Number:
  US11/676,207
• Publication Number:
  US 20070147338A1
• Time in Patent Office: 1,719 Days
• Field of Search: 370/315, 370/252, 370/253, 370229-235, 370/238, 370241-247, 370/338, 455/423, 455/8, 455/9
• US Class Current: 370/315
• CPC Class Codes: H04J 3/06 Synchronising arrangements for television systems H04N5/04; bit-synchronisation H04L7/00
• CPC Class Codes: H04W 36/14 Reselecting a network or an air interface
• CPC Class Codes: H04W 48/18 Selecting a network or a communication service
• CPC Class Codes: H04W 8/22 Processing or transfer of terminal data, e.g. status or physical capabilities
• CPC Class Codes: H04W 8/24 Transfer of terminal data
• CPC Class Codes: H04W 8/245 from a network towards a terminal
• CPC Class Codes: H04W 88/06 adapted for operation in multiple networks or having at least two operational modes, e.g. multi-mode terminals

Abstract

Implementation of opportunistic use of stations in a wireless network as repeaters is described. In one implementation, a station detects the existence of rate anomaly in a wireless network. In response to the rate anomaly, the station may transform into a software repeater for certain other neighboring stations. The repeater function allows for the relaying of packets sent by these neighboring stations to the access point and vice versa. The other neighboring stations, owing to their relative proximity to the repeater station, transmit data at a higher rate to the repeater station. Thus, the removal of the slower stations reduces clogging of the access point and increases the overall data rate within the wireless network. Further, a zero-overhead network coding protocol may be implemented in conjunction with the repeater function to increase capacity of the wireless network.

Claims

1. A method comprising:

detecting rate anomaly suffered by one or more stations in a wireless network, the rate anomaly existing if the one or more stations transmitting or receiving data suffer from throughput degradation, the detecting comprising;

collecting information from one or more other stations in the wireless network, the information comprising at least MAC identifiers of the one or more other stations, number of packets heard from each of the one or more other stations, average size of the packets heard, RSSI and data rate of the packets heard, and BSSID of the wireless network;

computing airtime consumed by each of the one or more other stations based on the number of packets heard, the average size of the packets heard, and the data rate of the packets heard;

determining utilization of a wireless medium by adding airtime consumed by the one or more other stations from the collected information; and

ascertaining existence of the rate anomaly, the rate anomaly existing when the utilization of the wireless medium is greater than a threshold and the one or more other stations suffer from throughput degradation; and

requesting the one or more stations to activate a repeater function implemented as a software at the one or more stations based on the detecting.

2. A method as recited in claim 1, further comprising:

using a network coding protocol to increase capacity of the wireless network, wherein the network coding protocol comprises;

buffering packets sent or received by each of the one or more stations in the wireless network;

receiving at the one or more stations activating the repeater function, a first packet from an access point for a first station using the repeater function, and a second packet from the first station for the access point;

mixing the first packet and the second packet to form a mixed packet;

broadcasting the mixed packet to the one or more other stations in the wireless network; and

decoding the mixed packet at the access point and the first station based on the buffered packets.

3. A method as recited in claim 1, wherein the requesting further comprises determining whether activation of the repeater function at the one or more stations would improve expected throughput of the one or more stations activating the repeater function and to performance of the wireless network.

4. A method as recited in claim 1, wherein the requesting further comprises broadcasting a message to one or more other stations in the wireless network seeking activation of the repeater function at the one or more other stations to alleviate the rate anomaly.

5. One or more computer-readable storage media storing computer-executable instructions that, when executed by one or more processors, perform acts comprising:

detecting rate anomaly suffered by one or more stations in a wireless network, the rate anomaly existing when the one or more stations transmitting or receiving data suffer from throughput degradation, the detecting comprising;

collecting information from one or more other stations in the wireless network, the information comprising at least MAC identifiers of the one or more other stations, number of packets heard from each of the one or more other stations, average size of the packets heard, signal strength and data rate of the packets heard;

computing airtime consumed by each of the one or more other stations;

determining utilization of a wireless medium based at least in part on the airtime consumed; and

ascertaining existence of the rate anomaly, the rate anomaly existing when the utilization of the wireless medium is greater than a threshold and at least a subset of the one or more other stations suffer from throughput degradation; and

requesting the one or more stations to activate a repeater function implemented as a software at the one or more stations based on the detecting.

6. The one or more computer-readable storage media as recited in claim 5, the computing airtime consumed being based at least in part on the number of packets heard, the average size of the packets heard and the data rate of the packets heard.

7. The one or more computer-readable storage media as recited in claim 5, the determining utilization being based at least in part on the airtime consumed by adding the airtime consumed by the one or more other stations from the collected information.

8. The one or more computer-readable media as recited in claim 5, the acts further comprising:

using a network coding protocol to increase capacity of the wireless network, wherein the network coding protocol comprises;

buffering packets locally sent or received by each of the one or more stations in the wireless network;

receiving at the one or more stations activating the repeater function, a first packet from an access point for a first station using the repeater function, and a second packet from the first station for the access point;

mixing the first packet and the second packet to form a mixed packet;

broadcasting the mixed packet to the one or more other stations in the wireless network; and

decoding the mixed packet at the access point and the first station based on the buffered packets.

9. The one or more computer-readable storage media as recited in claim 5, the requesting further comprising determining whether activation of the repeater function at the one or more stations would improve expected throughput of the one or more stations activating the repeater function and to performance of the wireless network.

10. The one or more computer-readable storage media as recited in claim 5, the requesting further comprising broadcasting a message to one or more other stations in the wireless network seeking activation of the repeater function at the one or more other stations to alleviate the rate anomaly.

11. A method comprising:

detecting rate anomaly suffered by one or more stations in a wireless network, the rate anomaly existing when the one or more stations transmitting or receiving data suffer from throughput degradation, the detecting including;

collecting information from one or more other stations in the wireless network, the information comprising at least MAC identifiers of the one or more other stations, number of packets heard from each of the one or more other stations, average size of the packets heard, signal strength and data rate of the packets heard;

computing airtime consumed by each of the one or more other stations;

determining utilization of a wireless medium based at least in part on the airtime consumed; and

ascertaining existence of the rate anomaly, the rate anomaly existing when the utilization of the wireless medium is greater than a threshold and at least a subset of the one or more other stations suffer from throughput degradation; and

requesting the one or more stations to activate a repeater function implemented as a software at the one or more stations based on the detecting.

12. The method as recited in claim 11, the computing airtime consumed being based at least in part on the number of packets heard, the average size of the packets heard and the data rate of the packets heard.

13. The method as recited in claim 11, the determining utilization being based at least in part on the airtime consumed by adding the airtime consumed by the one or more other stations from the collected information.

14. The method as recited in claim 11, the method further comprising:

using a network coding protocol to increase capacity of the wireless network, wherein the network coding protocol comprises;

buffering packets locally sent or received by each of the one or more stations in the wireless network;

receiving at the one or more stations activating the repeater function, a first packet from an access point for a first station using the repeater function, and a second packet from the first station for the access point;

mixing the first packet and the second packet to form a mixed packet;

broadcasting the mixed packet to the one or more other stations in the wireless network; and

decoding the mixed packet at the access point and the first station based on the buffered packets.

15. The method as recited in claim 11, the requesting further comprising determining whether activation of the repeater function at the one or more stations would improve expected throughput of the one or more stations activating the repeater function and to performance of the wireless network.

16. The method as recited in claim 11, the requesting further comprising broadcasting a message to one or more other stations in the wireless network seeking activation of the repeater function at the one or more other stations to alleviate the rate anomaly.