Method and apparatus for transmitting control information in WLAN system

• US 9,042,331 B2
• Filed: 01/28/2014
• Issued: 05/26/2015
• Est. Priority Date: 09/09/2009
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Dae Won, Roh, Dong Wook, Kang, Byeong Woo, Seok, Yong Ho, Noh, Yu Jin, Kim, Bong Hoe
• Primary Examiner(s): Nguyen, Brian D
• Application Number:
  US14/166,621
• Publication Number:
  US 20140140312A1
• Time in Patent Office: 483 Days
• Field of Search: 370/329, 370/330, 370/338, 370/343
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0413 MIMO systems
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0456 Selection of precoding matrices or codebooks, e.g. using matrices antenna weighting
• CPC Class Codes: H04B 7/0473 taking constraints in layer or codeword to antenna mapping into account
• CPC Class Codes: H04B 7/0486 taking channel rank into account
• CPC Class Codes: H04B 7/0617 for beam forming
• CPC Class Codes: H04L 27/2613 Structure of the reference signals
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• CPC Class Codes: H04L 5/0091 Signaling for the administration of the divided path
• CPC Class Codes: H04L 5/0094 Indication of how sub-channels of the path are allocated
• CPC Class Codes: H04W 72/046 the resource being in the space domain, e.g. beams
• CPC Class Codes: H04W 72/20 Control channels or signalling for resource management
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

There is provided a method of transmitting control information in a Wireless Local Area Network (WLAN) system, comprising transmitting first control information by means of cyclic shift delay diversity beam-forming and transmitting second control information. The first control information comprises information necessary for each of a plurality of target stations of the second control information to receive the second control information. The second control information beamformed and transmitted to the plurality of target stations.

Claims

1. A method of signal transmission in a Wireless Local Area Network (WLAN) system, the method comprising:

generating, by a station, a first very high throughput (VHT) signal containing control information;

generating, by the station, a second VHT signal containing control information; and

transmitting, by the station, the first VHT signal and the second VHT signal to at least one target station, wherein the first VHT signal includes an indicator indicating that the second VHT signal is to be transmitted by using a single-user multiple input multiple output (SU-MIMO) scheme or a multi-user multiple input multiple output (MU-MIMO) scheme.

2. The method of claim 1, further comprising:

applying a multi-user multiple input multiple output (MU-MIMO) steering matrix to the second VHT signal to form a pre-coded second control signal.

3. The method of claim 1, wherein the second VHT signal includes a modulation and coding scheme (MCS) index indicating a MCS used in the transmitting step.

4. The method of claim 1, wherein the first VHT signal includes a spatial stream identifier indicating a number of spatial streams for each of the at least one target station used in the transmitting step.

5. The method of claim 1, wherein the first VHT signal is transmitted over first data subcarriers in each of two orthogonal frequency division multiplexing (OFDM) symbols and the second VHT signal is transmitted over second data subcarriers in one OFDM symbol.

6. The method of claim 5, wherein the number of the first data subcarriers is 48 and the number of the second data subcarriers is 52.

7. The method of claim 1, wherein when the second VHT signal is to be transmitted to a plurality of target stations, different scrambling codes are applied to signals transmitted to the plurality of target stations.

8. The method of claim 1, wherein an identification value indicating one of the at least one target station is included in the first VHT signal or the second VHT signal.

9. The method of claim 1, further comprising:

applying a column matrix to the second VHT signal to form a pre-coded signal, wherein a number of row of the column matrix is determined based on a number of spatial streams for each of the at least one target station.

10. The method of claim 1, wherein a first cyclic shift is applied to the first VHT signal and a second cyclic shift is applied to the second VHT signal.

11. The method of claim 1, wherein the first VHT signal indicates a number of spatial streams for the at least one target station.

12. The method of claim 1, wherein when the second VHT signal is to be transmitted to a plurality of target stations, the first VHT signal indicates a total number of spatial streams for the plurality of target stations.

13. The method of claim 1, wherein the first control signal includes indication information indicating at least one spatial stream of another target station.

14. The method of claim 13, wherein the indication information is used to reduce interference caused by the at least one spatial stream of another target station.

15. A radio apparatus for signal transmission in a Wireless Local Area Network (WLAN) system, the radio apparatus comprising:

a processor configured to;

generate a first very high throughput (VHT) signal containing control information; and

generate a second VHT signal containing control information; and

a transceiver configured to;

transmit the first VHT signal and the second VHT signal to at least one target station, wherein the first VHT signal includes an indicator indicating that the second VHT signal is to be transmitted by using a single-user multiple input multiple output (SU-MIMO) scheme or a multi-user multiple input multiple output (MU-MIMO) scheme.

16. The radio apparatus of claim 15, wherein the processor is configured to apply a multi-user multiple input multiple output (MU-MIMO) steering matrix to the second VHT signal to form a pre-coded second control signal.

17. The radio apparatus of claim 15, wherein the second VHT signal includes a modulation and coding scheme (MCS) index indicating a MCS used in the transmission of the first VHT signal and the second VHT signal.

18. The radio apparatus of claim 15, wherein the first VHT signal includes a spatial stream identifier indicating a number of spatial streams for each of the at least one target station used in the transmission of the first VHT signal and the second VHT signal.

19. The radio apparatus of claim 15, wherein the first VHT signal is transmitted over first data subcarriers in each of two orthogonal frequency division multiplexing (OFDM) symbols and the second VHT signal is transmitted over second data subcarriers in one OFDM symbol.

20. The radio apparatus of claim 19, wherein the number of the first data subcarriers is 48 and the number of the second data subcarriers is 52.

21. The radio apparatus of claim 15, wherein when the second VHT signal is to be transmitted to a plurality of target stations, different scrambling codes are applied to signals transmitted to the plurality of target stations.

22. The radio apparatus of claim 15, wherein an identification value indicating one of the at least one target station is included in the first VHT signal or the second VHT signal.

23. The radio apparatus of claim 15, wherein the processor is further configured to apply a column matrix to the second VHT signal to form a pre-coded signal, wherein a number of row of the column matrix is determined based on a number of spatial streams for each of the at least one target station.

24. The radio apparatus of claim 15, wherein a first cyclic shift is applied to the first VHT signal and a second cyclic shift is applied to the second VHT signal.

25. The radio apparatus of claim 15, wherein the first VHT signal indicates a number of spatial streams for the at least one target station.

26. The radio apparatus of claim 15, wherein when the second VHT signal is to be transmitted to a plurality of target stations, the first VHT signal indicates a total number of spatial streams for the plurality of target stations.

27. The radio apparatus of claim 15, wherein the first control signal includes indication information indicating at least one spatial stream of another target station.

28. The radio apparatus of claim 27, wherein the indication information is used to reduce interference caused by the at least one spatial stream of another target station.

29. A radio apparatus for signal transmission in a Wireless Local Area Network (WLAN) system, the radio apparatus comprising:

a means for;

generating, by a station, a first very high throughput (VHT) signal containing control information; and

generating, by the station, a second VHT signal containing control information; and

a means for transmitting the first VHT signal and the second VHT signal to at least one target station, wherein the first VHT signal includes an indicator indicating that the second VHT signal is to be transmitted by using a single-user multiple input multiple output (SU-MIMO) scheme or a multi-user multiple input multiple output (MU-MIMO) scheme.

30. The radio apparatus of claim 29, further comprising:

applying a multi-user multiple input multiple output (MU-MIMO) steering matrix to the second VHT signal to form a pre-coded second control signal.

31. The radio apparatus of claim 29, wherein the first VHT signal is transmitted over first data subcarriers in each of two orthogonal frequency division multiplexing (OFDM) symbols and the second VHT signal is transmitted over second data subcarriers in one OFDM symbol.

32. The radio apparatus of claim 29, wherein when the second VHT signal is to be transmitted to a plurality of target stations, different scrambling codes are applied to signals transmitted to the plurality of target stations.

33. The radio apparatus of claim 29, wherein an identification value indicating one of the at least one target station is included in the first VHT signal or the second VHT signal.

34. The radio apparatus of claim 29, wherein a first cyclic shift is applied to the first VHT signal and a second cyclic shift is applied to the second VHT signal.

35. The radio apparatus of claim 29, wherein the first VHT signal indicates a number of spatial streams for the at least one target station.

36. The radio apparatus of claim 29, wherein when the second VHT signal is to be transmitted to a plurality of target stations, the first VHT signal indicates a total number of spatial streams for the plurality of target stations.

37. The radio apparatus of claim 29, wherein the first control signal includes indication information indicating at least one spatial stream of another target station.

38. The radio apparatus of claim 37, wherein the indication information is used to reduce interference caused by the at least one spatial stream of another target station.