System and method for preambles in a wireless communications network

• US 9,713,031 B2
• Filed: 06/04/2015
• Issued: 07/18/2017
• Est. Priority Date: 12/07/2011
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Li, Yunbo, Suh, Jung Hoon, Au, Kwok Shum, Aboul-Magd, Osama, Sun, Sheng
• Primary Examiner(s): Mui, Gary
• Application Number:
  US14/730,728
• Publication Number:
  US 20150271704A1
• Time in Patent Office: 775 Days
• Field of Search: None
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04B 7/0689 using different transmission schemes, at least one of them being a diversity transmission scheme
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0048 Allocation of pilot signals, i.e. of signals known to the receiver
• CPC Class Codes: H04L 5/0053 Allocation of signaling, i.e. of overhead other than pilot signals
• CPC Class Codes: H04L 69/22 Parsing or analysis of headers
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method for transmitting a frame includes generating an omni portion of the frame, the omni portion including a non-beamformed long training field and a signal field, the non-beamformed long training field including channel estimation information used to decode the signal field, the non-beamformed long training field configured to be transmitted through one of multiple antennas and multiple streams. The method also includes generating a multi-stream portion of the frame, the multi-stream portion including a data field and a multi-stream long training field, the multi-stream long training field including station-specific decoding information for station-specific data in the data field. The method further includes applying a beamforming indicator to the signal field of the omni portion, and transmitting the frame.

Claims

1. A method for transmitting a frame, the method comprising:

generating, by an access point, a non-beamformed omni portion of the frame, wherein the non-beamformed omni portion includes a short training field, a first long training field and a signal field, wherein the first long training field includes channel estimation information for decoding the signal field, and wherein the signal field includes a beam forming field indicating whether beamforming is used for a multi-stream portion of the frame;

generating, by the access point, the multi-stream portion of the frame, wherein the multi-stream portion of the frame is located after the omni portion of the frame, wherein the multi-stream portion includes a second long training field and a data field, and wherein the second long training field includes reference signal information for channel estimation of station-specific data in the data field; and

wirelessly transmitting, by the access point, the frame.

2. The method of claim 1, further comprising setting the beam forming field to a first value indicating the multi-stream portion of the frame is beamformed.

3. The method of claim 2, wherein the beam forming field is a one-bit value set to one.

4. The method of claim 1, further comprising setting the beam forming field to a second value indicating the multi-stream portion of the frame is not beamformed.

5. The method of claim 4, wherein the beam forming field is a one-bit value set to zero.

6. The method of claim 1, wherein transmitting the frame comprises transmitting the non-beamformed omni portion of the frame through one stream.

7. The method of claim 6, wherein transmitting the frame comprises transmitting the multi-stream portion of the frame through multiple antennas and multiple streams.

8. The method of claim 1, wherein the beam forming field indicates whether a Q matrix is changed from the omni portion of the frame to the multi-stream portion of the frame.

9. A method for receiving a frame, the method comprising:

wirelessly receiving, by a station, a non-beamformed omni portion of the frame, wherein the non-beamformed omni portion includes a short training field, a first long training field and a signal field, wherein the first long training field includes channel estimation information for decoding the signal field, and wherein the signal field includes a beam forming field;

decoding, by the station, the beam forming field to determine whether a multi-stream portion of the frame is beamformed;

wirelessly receiving, by the station, the multi-stream portion of the frame, wherein the multi-stream portion of the frame is located after the omni portion of the frame, wherein the multi-stream portion includes a second long training field and a data field, and wherein the second long training field includes reference signal information for channel estimation of station-specific data in the data field; and

decoding, by the station, the multi-stream portion of the frame in accordance with the decoded beam forming field.

10. The method of claim 9, wherein decoding the beam forming field comprises determining the beam forming field has a first value indicating the multi-stream portion of the frame is beamformed.

11. The method of claim 10, wherein the beam forming field is a one-bit value equal to one.

12. The method of claim 9, wherein decoding the beam forming field comprises determining the beam forming field has a second value indicating the multi-stream portion of the frame is not beamformed.

13. The method of claim 12, wherein the beam forming field is a one-bit value equal to zero.

14. The method of claim 9, wherein the beam forming field indicates whether a Q matrix is changed from the omni portion of the frame to the multi-stream portion of the frame.

15. An access point comprising:

a processor configured for;

generating a non-beamformed omni portion of a frame, wherein the non-beamformed omni portion includes a short training field, a first long training field and a signal field, wherein the first long training field includes channel estimation information for decoding the signal field, and wherein the signal field includes a beam forming field indicating whether beamforming is used for a multi-stream portion of the frame; and

generating the multi-stream portion of the frame, wherein the multi-stream portion of the frame is located after the omni portion of the frame, wherein the multi-stream portion includes a second long training field and a data field, and wherein the second long training field includes reference signal information for channel estimation of station-specific data in the data field; and

a transmitter coupled to the processor and configured for wirelessly transmitting the frame.

16. The access point of claim 15, wherein the processor is further configured for setting the beam forming field to a first value indicating the multi-stream portion of the frame is beamformed.

17. The access point of claim 16, wherein the beam forming field is a one-bit value set to one.

18. The access point of claim 15, wherein the processor is further configured for setting the beam forming field to a second value indicating the multi-stream portion of the frame is not beamformed.

19. The access point of claim 18, wherein the beam forming field is a one-bit value set to zero.

20. The access point of claim 15, wherein the transmitter configured for transmitting the frame comprises the transmitter configured for transmitting the non-beamformed omni portion of the frame through one stream.

21. The access point of claim 20, wherein the transmitter configured for transmitting the frame comprises the transmitter configured for transmitting the multi-stream portion of the frame through multiple antennas and multiple streams.

22. The access point of claim 15, wherein the beam forming field indicates whether a Q matrix is changed from the omni portion of the frame to the multi-stream portion of the frame.

23. A station comprising:

a receiver configured for wirelessly receiving a non-beamformed omni portion of a frame, wherein the non-beamformed omni portion includes a short training field, a first long training field and a signal field, wherein the first long training field includes channel estimation information for decoding the signal field, and wherein the signal field includes a beam forming field;

a processor coupled to the receiver and configured for decoding the beam forming field to determine whether a multi-stream portion of the frame is beamformed;

the receiver further configured for wirelessly receiving the multi-stream portion of the frame, wherein the multi-stream portion of the frame is located after the omni portion of the frame, wherein the multi-stream portion includes a second long training field and a data field, and wherein the second long training field includes reference signal information for channel estimation of station-specific data in the data field; and

the processor further configured for decoding the multi-stream portion of the frame in accordance with the decoded beam forming field.

24. The station of claim 23, wherein the processor configured for decoding the beam forming field comprises the processor configured for determining the beam forming field is a first value indicating the multi-stream portion of the frame is beamformed.

25. The station of claim 24, wherein the beam forming field is a one-bit value equal to one.

26. The station of claim 23, wherein the processor configured for decoding the beam forming field comprises the processor configured for determining the beam forming field is a second value indicating the multi-stream portion of the frame is not beamformed.

27. The station of claim 26, wherein the beam forming field is a one-bit value equal to zero.

28. The station of claim 23, wherein the beam forming field indicates whether a Q matrix is changed from the omni portion of the frame to the multi-stream portion of the frame.