Trained data transmission for communication systems

• US 7,373,112 B2
• Filed: 11/20/2003
• Issued: 05/13/2008
• Est. Priority Date: 08/08/2003
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Intel Corporation
• Inventors: Jacobsen, Eric A., Stephens, Adrian P., Sandhu, Sumeet, Kitchin, Duncan M.
• Primary Examiner(s): PHU, SANH D
• Application Number:
  US10/719,208
• Publication Number:
  US 20050032478A1
• Time in Patent Office: 1,636 Days
• Field of Search: 455/517, 455/452.1, 455/67.11, 455/423, 370/328, 370/329
• US Class Current: 455/67.11
• CPC Class Codes: H04W 72/23 in the downlink direction of a wireless link, i.e. towards a terminal
• CPC Class Codes: H04W 72/54 based on quality criteria
• CPC Class Codes: H04W 74/08 Non-scheduled access, e.g. ALOHA hybrid access H04W74/02

Abstract

Various embodiments are described for a trained data transmission for communication systems.

Claims

1. A method comprising:

receiving a medium reservation request message at an access point to initiate training and to request a medium reservation, said medium reservation request message includes training information comprising a training sequence;

sending a medium reservation reply message from said access point granting a medium reservation request and providing training feedback describing at least one measured transmission condition measured on a per antenna basis using each antenna where multiple antenna are used at said access point; and

selecting at least one data transmission parameter based on the received training feedback.

2. The method of claim 1 and further comprising transmitting data according to the at least one data transmission parameter.

3. The method of claim 1 wherein the feedback describing at least one measured transmission condition comprises at least one from the group comprising:

a measured signal to noise ratio;

a presence of errors or not in received training information or other information;

a number of errors detected;

a bit error rate or packet error rate; and

a measured signal strength.

4. The method of claim 3 wherein the measured transmission condition is measured on a per subcarrier basis.

5. The method of claim 1 wherein the selecting at least one data transmission parameter comprises selecting a data transmission parameter from the group including:

a data rate;

a modulation scheme;

a coding rate;

use and/or type of interleaving; and

transmission power.

6. The method of claim 5 wherein the selected data transmission parameter is selected on a per subcarrier basis.

7. The method of claim 1 and further comprising obtaining access to a wireless transmission medium prior to the transmitting a medium reservation request message.

8. The method of claim 1 wherein the obtaining access comprises performing one from the group including:

obtaining access to a wireless medium using a polling access technique; and

obtaining access to a wireless medium using a contention based access technique.

9. The method of claim 1 and further comprising:

receiving the medium reservation request message;

measuring a transmission condition in response to the medium reservation request message; and

transmitting the medium reservation reply message to grant the medium reservation request, the medium reservation reply message including training feedback.

10. The method of claim 9 wherein the measuring comprises measuring a transmission condition based on training information provided in the medium reservation request message.

11. The method of claim 9 wherein the medium reservation reply message includes training feedback, the training feedback comprising at least one of:

feedback describing at least one measured transmission condition; and

feedback specifying at least one data transmission parameter to be used for transmitting data.

12. The method of claim 1 wherein at least one of the medium reservation request message and the medium reservation reply message include a duration field to specify a duration of the requested medium reservation.

13. The method of claim 1 wherein the medium reservation request message comprises a request-to-send type message and which also initiates a receiving station to measure a transmission condition for training.

14. The method of claim 1 wherein the request-to-send type message that also includes training information.

15. The method of claim 1 wherein the medium reservation reply message comprises a clear-to-send type message that also includes training feedback.

16. The method of claim 1 and further comprising sending data via the reserved medium according to the at least one selected transmission parameter.

17. A method comprising:

receiving at a first station a medium reservation request message sent from a second station, said medium reservation request message includes training information composing a training sequence;

measuring a transmission condition in response to the medium reservation request message; and

transmitting a medium reservation reply message from the first station to the second station, the medium reservation reply message granting the medium reservation request from the second station and including training feedback describing at least one measured transmission condition measured on a per antenna basis using each antenna where multiple antenna are used at said first station, said training feedback to be used by the second station to select or adapt at least one transmission parameter.

18. The method of claim 17 and further comprising the second station selecting at least one data transmission parameter based on the received training feedback.

19. The method of claim 17 wherein the measuring comprises measuring a transmission condition based on the training information in response to the medium reservation request message.

20. An apparatus comprising a processor and a wireless transceiver, the apparatus adapted to receive a medium reservation request message via a wireless link at a first station to initiate training and to request a medium reservation, said medium reservation request message includes training information comprising a training sequence, the apparatus further adapted to select at least one data transmission parameter based upon training feedback describing at least one measured transmission condition measured on a per antenna basis using each antenna where multiple antenna are used at said first station, said training feedback included within a medium reservation reply message sent from the first station.

21. The apparatus of claim 20 wherein the medium reservation request message and the medium reservation reply message each comprise a duration field indicating a duration of the requested medium reservation.

22. The apparatus of claim 20 wherein the apparatus is adapted to send a medium reservation request message via a wireless link to a first station to initiate training and to request a medium reservation, the medium reservation request message including training information to allow the first station to measure a transmission condition.

23. The apparatus of claim 20, wherein the wireless system further comprises a memory coupled to the processor, and an antenna coupled to the wireless transceiver.

24. An apparatus comprising a processor and a wireless transceiver, the apparatus adapted to receive a medium reservation request message via a wireless link from a first station, said medium reservation request message includes training information comprising a training sequence, the apparatus further adapted to measure a transmission condition and send a medium reservation reply message to the first station, the medium reservation reply message granting the requested medium reservation and including training feedback describing at least one measured transmission condition measured on a per antenna basis using each antenna where multiple antenna are used at said apparatus, said training feedback to allow the first station to select at least one transmission parameter.

25. The apparatus of claim 24 wherein the medium reservation request message includes training information, the apparatus adapted to measure a transmission condition based on the received training information.

26. A method of transmitting information between first and second wireless stations, the method comprising:

a training phase, the training phase including sending a medium reservation request message from the first station to the second station to request a medium reservation, said medium reservation request message includes training information comprising a training sequence, measuring a transmission condition in response to the medium reservation request message, and sending a medium reservation reply message from the second station to the first station to grant the requested medium reservation and providing training feedback describing at least one measured transmission condition measured on a per antenna basis using each antenna where multiple antenna are used at said second station, the second station selecting at least one data transmission parameter based upon the received training feedback; and

a data phase, where at least one data message is sent from the first station to the second station via the reserved medium according to the selected data transmission parameter.

27. The method of claim 26 wherein the medium reservation request message and the medium reservation reply message include a duration field indicating a duration of the requested medium reservation.

28. The method of claim 26 wherein the medium reservation request message and the medium reservation reply message comprise legacy-compatible RTS and CTS messages, respectively.