METHOD AND APPARATUS FOR TRANSMITTING CONTROL INFORMATION IN WLAN SYSTEM

• US 20120127940A1
• Filed: 09/08/2010
• Published: 05/24/2012
• 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
• Granted Patent: US 8,675,597 B2
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04B 7/0671 using different delays between antennas
• CPC Class Codes: H04L 25/0226 sounding signals per se
• CPC Class Codes: H04L 25/03343 Arrangements at the transmitter end
• CPC Class Codes: H04L 5/001 the frequencies being arranged in component carriers
• CPC Class Codes: H04L 5/0023 Time-frequency-space
• 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: 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

1-12. -12. (canceled)

13. A method of transmitting control information by an access point in a Wireless Local Area Network (WLAN) system, the method comprising:

generating, by the access point, a first control sequence including a first very high throughput control signal (VHTSIG-A) containing control information which is commonly received by a plurality of target stations;

generating, by the access point, a second control sequence including a second very high throughput control signal (VHTSIG-B) containing control information which is specifically received by each of the plurality of target stations;

generating, by the access point, a first time domain signal by modulating the first control sequence;

generating, by the access point, a second time domain signal by modulating the second control sequence; and

transmitting, by the access point, the first time domain signal and the second time domain signal to the plurality of stations.

14. The method of claim 13, further comprising:

applying a multi-user multiple input multiple output (MU-MIMO) steering matrix to the second control sequence to form a pre-coded second control signal prior to the step of modulating the second control sequence.

15. The method of claim 13, wherein the VHTSIG-B includes a modulation and coding scheme (MCS) index indicating a MCS used in the step of transmitting.

16. The method of claim 13,

wherein the VHTSIG-A includes a channel bandwidth identifier indicating a channel width used in the step of transmitting and a spatial stream identifier indicating a number of spatial streams for each of the plurality of target stations used in the step of transmitting.

17. The method of claim 13,

wherein the VHTSIG-A consists of a first number of information bits/symbol and the VHTSIG-B consists of a second number of information bits/symbol greater than the first number of bits/symbol.

18. The method of claim 17,

wherein the first number of information bits/symbol is 24 and the second number of information bits/symbol is at least 26.

19. A wireless apparatus of transmitting control information in a Wireless Local Area Network (WLAN) system, the apparatus comprising a processor configured to:

generate a first control sequence including a first very high throughput control signal (VHTSIG-A) containing control information which is commonly received by a plurality of target stations;

generate a second control sequence including a second very high throughput control signal (VHTSIG-B) containing control information which is specifically received by each of the plurality of target stations;

generate a first time domain signal by modulating the first control sequence;

generate a second time domain signal by modulating the second control sequence; and

transmit the first time domain signal and the second time domain signal to the plurality of stations.

20. The apparatus of claim 19, the processor further configured to:

apply a multi-user multiple input multiple output (MU-MIMO) steering matrix to the second control sequence to form a pre-coded second control signal prior to the step of modulating the second control sequence.

21. The apparatus of claim 19, wherein the VHTSIG-B includes a modulation and coding scheme (MCS) index indicating a MCS used in the step of transmitting.

22. The apparatus of claim 19, wherein the VHTSIG-A includes a channel bandwidth identifier indicating a channel width used in the step of transmitting and a spatial stream identifier indicating a number of spatial streams for each of the plurality of target stations used in the step of transmitting.

23. The apparatus of claim 19, wherein the VHTSIG-A consists of a first number of information bits/symbol and the VHTSIG-B consists of a second number of information bits/symbol greater than the first number of bits/symbol.

24. The apparatus of claim 23, wherein the first number of information bits/symbol is 24 and the second number of information bits/symbol is at least 26.