Aligning 802.11e HCF and 802.11h TPC operations

• US 20030012165A1
• Filed: 04/10/2002
• Published: 01/16/2003
• Est. Priority Date: 07/09/2001
• Status: Active Grant

• Current Assignee: Atreus Labs LLC
• Original Assignee: Koninklijke Philips Electronics N.V. (Koninklijke Philips N.V.)
• Inventors: Choi, Sunghyun, Soomro, Amjad, del Prado Pavon, Javier
• Granted Patent: US 7,245,592 B2
• Time in Patent Office: Days
• US Class Current: 370/338
• CPC Class Codes: H04W 52/367 Power values between minimum and maximum limits, e.g. dynamic range
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]
• CPC Class Codes: H04W 92/18 between terminal devices

Abstract

A granted TxOP holder transmits the first frame of a QSTA-to-QSTA communication at a power level sufficient to ensure correct reception by the destination and at least detection by the HC, and then, with exceptions, transmits subsequent frames at a power level merely sufficient to ensure correct reception by the destination, regardless of reception or detection by the HC. Subsequent frames that must be received by the HC, such as those changing the TC queue size or requesting extension of the current TxOP, are transmitted at a power sufficient to ensure reception by the HC as well as the destination, as are the last frame(s). The HC is constrained from reclaiming the channel unconditionally merely because of failure to detect activity, and recovery is limited to the TxOP holder.

Claims

1. A portion of a wireless communications system comprising:

a first station selectively capable of station-to-station communication with one or more other stations, the first station operable to control transmit power,

wherein the first station is adapted to transmit a first frame for a station-to-station communication with the one or more other stations at a power level sufficient for both correct reception of the first frame by the one or more other stations and at least detection of the first frame by a hybrid coordination function controller, and to transmit subsequent frames for the station-to-station communication at a power level merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller.

2. The portion of a wireless communications system according to claim 1, wherein the first station is adapted to selectively transmit one or more frames following the first frame and the subsequent frames for the station-to-station communication at a power level sufficient for correct reception of the one or more frames by both the one or more other stations and the hybrid coordination function controller, and

wherein the one or more other stations are adapted to selectively transmit selected frames which must be correctly received by the hybrid coordination function controller at a power level sufficient for correct reception of the one or more frames by the hybrid coordination function controller and any other stations involved with the station-to-station communication.

3. The portion of a wireless communications system according to claim 2, wherein the one or more frames are selected from the group comprising:

frames changing a traffic category queue size;

frames requesting a change in duration of the station-to-station communication;

frames requesting an additional station-to-station communication; and

last frames within the station-to-station communication.

4. The portion of a wireless communications system according to claim 1, wherein the first station is operable for station-to-station communication while the hybrid coordination function controller is constrained from reclaiming a channel over which the first and subsequent frames are transmitted based upon failure to detect activity on the channel during the station-to-station communication.

5. The portion of a wireless communications system according to claim 1, wherein the first station is adapted to be the only station capable of initiating recovery from a communication failure during the station-to-station communication.

6. The portion of a wireless communications system according to claim 1, wherein the first station is adapted to transmit the subsequent frames at a data rate merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller.

7. The portion of a wireless communications system according to claim 1, wherein the power level at which the subsequent frames are transmitted is lower than the power level at which the first frame is transmitted.

8. A wireless communications system comprising:

a hybrid coordination function controller; and

stations selectively capable of station-to-station communication, at least a first station among the stations operable to control transmit power,

wherein the first station is adapted to transmit a first frame for a station-to-station communication with one or more other stations at a power level sufficient for both correct reception of the first frame by the one or more other stations and at least detection of the first frame by the hybrid coordination function controller, and to transmit subsequent frames for the station-to-station communication at a power level merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller.

9. The wireless communications system according to claim 8, wherein the first station is adapted to selectively transmit one or more frames following the first frame and the subsequent frames for the station-to-station communication at a power level sufficient for correct reception of the one or more frames by both the one or more other stations and the hybrid coordination function controller, and

wherein the one or more other stations are adapted to selectively transmit selected frames which must be correctly received by the hybrid coordination function controller at a power level sufficient for correct reception of the one or more frames by the hybrid coordination function controller and any other stations involved with the station-to-station communication.

10. The wireless communications system according to claim 9, wherein the one or more frames are selected from the group comprising:

frames changing a traffic category queue size;

frames requesting a change in duration of the station-to-station communication;

frames requesting an additional station-to-station communication; and

last frames within the station-to-station communication.

11. The wireless communications system according to claim 8, wherein the first station is operable for station-to-station communication while the hybrid coordination function controller is constrained from reclaiming a channel over which the first and subsequent frames are transmitted based upon failure to detect activity on the channel during the station-to-station communication.

12. The wireless communications system according to claim 8, wherein the first station is adapted to be the only station capable of initiating recovery from a communication failure during the station-to-station communication.

13. The wireless communications system according to claim 8, wherein the first station is adapted to transmit the subsequent frames at a data rate merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller.

14. The wireless communications system according to claim 8, wherein the power level at which the subsequent frames are transmitted is lower than the power level at which the first frame is transmitted.

16. The method according to claim 15, further comprising:

transmitting one or more frames following the first frame and the subsequent frames for the station-to-station communication at a third power level sufficient for correct reception of the one or more frames by both the one or more other stations and the hybrid coordination function controller; and

transmitting, from one of the one or more other stations, one or more frames responsive to frames transmitted by the first station which must be correctly received by the hybrid coordination function controller at a power level sufficient for correct reception of the one or more responsive frames by the hybrid coordination function controller and the first station.

17. The method according to claim 16, wherein the one or more frames are selected from the group comprising:

frames changing a traffic category queue size;

frames requesting a change in duration of the station-to-station communication;

frames requesting an additional station-to-station communication; and

last frames within the station-to-station communication.

18. The method according to claim 15, further comprising:

constraining the hybrid coordination function controller from reclaiming a channel over which the first and subsequent frames are transmitted based upon failure to detect activity on the channel during the station-to-station communication.

19. The method according to claim 15, wherein the first station is the only station capable of initiating recovery from a communication failure during the station-to-station communication.

20. The method according to claim 15, further comprising:

transmitting the subsequent frames at a data rate merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller.

15. A method of wireless communications comprising:

transmitting a first frame for a station-to-station communication from a first station to one or more other stations at a first power level sufficient for both correct reception of the first frame by the one or more other stations and at least detection of the first frame by a hybrid coordination function controller; and

transmitting subsequent frames for the station-to-station communication at a second power level merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller,

wherein the second power level is lower than the first power level.

21. A station-to-station communication, comprising:

a first frame from a first station to one or more other stations at a first power level sufficient for both correct reception of the first frame by the one or more other stations and at least detection of the first frame by a hybrid coordination function controller; and

subsequent frames following the first frame at a second power level merely sufficient for correct reception of the subsequent frames by the one or more other stations, regardless of reception or detection of the subsequent frames by the hybrid coordination function controller,

wherein the second power level is lower than the first power level.