Adaption of medium access and transmission parameters for wireless networks

• US 8,634,447 B2
• Filed: 07/23/2009
• Issued: 01/21/2014
• Est. Priority Date: 07/23/2009
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Diener, Neil Robert, Kruys, Johannes P., Qian, Lu
• Primary Examiner(s): KASSA, ZEWDU A
• Application Number:
  US12/508,028
• Publication Number:
  US 20110019721A1
• Time in Patent Office: 1,643 Days
• Field of Search: 375/219, 375/319, 375/295, 370/329, 370/465, 370/332, 370/252, 370/236, 370/468
• US Class Current: 375/219
• CPC Class Codes: H04W 28/18 Negotiating wireless communication parameters
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02
• CPC Class Codes: H04W 88/02 Terminal devices

Abstract

In accordance with an example embodiment, there is disclosed herein an apparatus where transmitter operating parameters are adjusted based on channel condition data obtained from a transmitter and/or from a receiver communicating with the transmitter. For example, the transmitter'"'"'s contention window may be increased responsive to determining channel occupancy at the receiver is increasing. As another example, aggregation/fragmentation may be adjusted based on channel occupancy at the receiver. Still another example, the data rate employed by the transmitter may be changed responsive to changes in receiver success count.

Claims

1. An apparatus, comprising:

a wireless transmitter;

logic coupled to the wireless transmitter and configured to control the operation of the transmitter;

wherein the logic is configured to obtain channel condition data from the transmitter;

wherein the logic is configured to obtain channel condition data from a receiver communicatively coupled with the wireless transmitter;

wherein the logic is configured to perform a smoothing function on channel condition data consisting of data obtained from the transmitter and channel condition data obtained by the receiver;

wherein the logic is configured to perform the smoothing function on the channel condition data in accordance with a series of previously obtained channel condition data over a specified span;

wherein the logic is configured to have the wireless transmitter employ an aggressive back-off responsive to determining that foreground interference is more dominant than background interference in accordance with smoothed channel condition data.

2. The apparatus set forth in claim 1, wherein the logic is configured to have the wireless transmitter employ a conservative back-off responsive to determining that background interference is more dominant than foreground interference.

3. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of channel occupancy;

and

wherein the logic is operable to decrease contention window size for the wireless transmitter responsive to determining that channel occupancy is decreasing.

4. The apparatus set forth in claim 3, wherein the channel condition data from the wireless transmitter comprises data representative of channel occupancy;

and

wherein the logic selects the channel occupancy that is the maximum of the channel occupancy at the receiver and the channel occupancy at the transmitter.

5. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of channel occupancy;

and

wherein the logic increases packet size of packets sent by the transmitter responsive to determining that the channel occupancy is decreasing.

6. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of channel occupancy;

and

wherein the logic is operable to increase a contention window for the wireless transmitter responsive to determining that channel occupancy is increasing.

7. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of channel occupancy;

and

wherein the logic decreases a packet size of packets sent by the transmitter responsive to determining that the channel occupancy is increasing.

8. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of receiver success count;

and

wherein the logic increases a contention window size responsive to determining the receiver success count is decreasing.

9. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of receiver success count;

and

wherein the logic decrease a contention window size responsive to determining the receiver success count is increasing.

10. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of receiver success count;

and

wherein the logic decreases a data rate responsive to determining a receiver success rate is decreasing.

11. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of receiver success count;

and

wherein the logic increases a data rate responsive to determining a receiver success rate is increasing.

12. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of signal to noise ratio measured at the receiver;

and

wherein the logic increases transmitter data rate responsive to determining the signal to noise ratio is increasing.

13. The apparatus set forth in claim 1, wherein the channel condition data from the receiver comprises data representative of signal to noise ratio measured at the receiver;

and

wherein the logic decreases transmitter data rate responsive to determining the signal to noise ratio is decreasing.

14. The apparatus set forth in claim 1, wherein the logic is configured to calculate an average channel occupancy and receiver success count for a preceding predetermined time period.

15. The apparatus set forth in claim 1, wherein the wireless transceiver communicates with a plurality of receivers;

wherein the logic is configured to receive channel condition data from each of the plurality of receivers; and

wherein the logic is configured maintain channel condition data for each of the plurality of receivers separately.

16. The apparatus set forth in claim 1, wherein the logic is configured to determine a receiver success counts for different packet durations.

17. The apparatus set forth in claim 1, wherein the logic is configured to obtain the channel condition data from the receiver from a Medium Access Control header of one of a group consisting of a data packet, a control frame and a management frame received from the receiver via the wireless transceiver.

18. The apparatus set forth in claim 1, wherein the logic is configured to obtain the channel condition data from the receiver from an information element from a frame received from the receiver via the wireless transceiver.

19. An apparatus, comprising:

a wireless transmitter;

logic coupled to the wireless transmitter and configured to control the operation of the transmitter;

wherein the logic is configured to obtain channel condition data from a receiver communicatively coupled with the wireless transmitter;

wherein the logic is configured to perform a smoothing function on channel condition data consisting of data obtained from the transmitter and channel condition data obtained by the receiver;

wherein the logic is configured to perform the smoothing function on the channel condition data in accordance with a series of previously obtained channel condition data over a specified span;

wherein the logic is configured to increase transmitter data rate responsive to determining from smoothed channel condition data from the receiver that receiver success count is increasing.

20. An apparatus, comprising:

a wireless transmitter;

logic coupled to the wireless transmitter and configured to control the operation of the transmitter;

wherein the logic is configured to obtain channel condition data consisting of data obtained from a receiver communicatively coupled with the wireless transmitter;

wherein the logic is configured to perform a smoothing function on the channel condition data;

wherein the logic is configured to perform the smoothing function on the channel condition data in accordance with a series of previously obtained channel condition data over a specified span;

wherein the logic is configured to decrease packet size responsive to determining that channel occupancy is increasing based on smoothed channel condition data received from the receiver.

21. A method, comprising:

obtaining channel condition data consisting of data obtained from a transmitter over a period of time;

obtaining channel condition data from a receiver communicatively coupled with the wireless transmitter over the period of time;

performing a smoothing function on the channel condition data in accordance with a series of previously obtained channel condition data over a specified span;

determining foreground and background interference over the specified span based on the channel condition data obtained from the transmitter and the channel condition data obtained from the receiver; and

decreasing a contention window, increasing a data rate, and increasing packet size responsive to determining foreground interference and background interference are decreasing over the period of time.

22. The method set forth in claim 21, further comprising:

obtaining channel condition data from a plurality of receivers communicatively coupled with the wireless transmitter; and

maintaining a separate setting for back-off, contention window, packet size, and data rate for communicating with each of the plurality of receivers.

23. The method set forth in claim 21, comprising:

obtaining a receiver success count based on a plurality of ranges of packet sizes; and

maintaining a separate setting for back-off, contention window, and data rate for each of the plurality of packet sizes.

24. The method set forth in claim 21, wherein the channel condition data obtained from the receiver comprises receiver success count and channel occupancy.

25. The method set forth in claim 21, changing a back-off setting to a conservative back-off setting responsive to determining that background interference is more dominant than foreground interference.