Method for transmitting control information and apparatus for the same

• US 8,718,173 B2
• Filed: 02/09/2011
• Issued: 05/06/2014
• Est. Priority Date: 02/12/2010
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Lee, Dae Won, Noh, Yu Jin, Kang, Byeong Woo, Seok, Yong Ho
• Primary Examiner(s): Fan, Chieh M
• Assistant Examiner(s): Stevens, Brian J
• Application Number:
  US13/520,769
• Publication Number:
  US 20120281774A1
• Time in Patent Office: 1,182 Days
• Field of Search: 375/267, 375/260, 375/259
• US Class Current: 375/267
• 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 7/06 at the transmitting station
• CPC Class Codes: H04L 27/2626 Arrangements specific to the transmitter only
• CPC Class Codes: H04L 27/2646 using feedback from receiver for adjusting OFDM transmission parameters, e.g. transmission timing or guard interval length
• CPC Class Codes: H04L 27/2647 Arrangements specific to the receiver only equalisation H04L27/01
• CPC Class Codes: H04L 27/28 with simultaneous transmission of different frequencies each representing one code element
• CPC Class Codes: H04L 69/323 in the physical layer [OSI layer 1]
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method and apparatus for transmitting control information in a wireless communication system is provided. The method includes transmitting common control information including a multiple input multiple output (MIMO) indicator indicating single user-MIMO (SU-MIMO) or multi user-MIMO (MU-MIMO) to a receiver, generating first precoded dedicated control information by performing precoding on dedicated control information including information for the MU-MIMO by the use of a first precoding matrix, generating second precoded dedicated control information by performing precoding on the first precoded dedicated control information by the use of a second precoding matrix and transmitting the second precoded dedicated control information to the receiver.

Claims

1. A method for transmitting a data unit in a wireless local area network, the method comprising:

transmitting, by a transmitter, a very high throughput (VHT)-SIG-A field to a receiver;

transmitting, by the transmitter, a very high throughput (VHT)-long training field (LTF) for multiple input multiple output (MIMO) channel estimation to the receiver;

transmitting, by the transmitter, a VHT-SIG-B field to the receiver; and

transmitting, by the transmitter, a data field to the receiver;

wherein the VHT-SIG-A field, the VHT-LTF, the VHT-SIG-B field and the data field are sequentially transmitted,

wherein the VHT-SIG-A field includes a spatial streams indicator indicating a number of spatial streams for transmitting the data field,

wherein the VHT-LTF is applied by a first mapping matrix and a second mapping matrix,

wherein the data field is applied by the second mapping matrix,

wherein the VHT-SIG-B field is applied by a column of the first mapping matrix and the second mapping matrix and is mapped to the spatial streams based on the applied first mapping matrix,

wherein the VHT-SIG-A field is not applied by any of the first mapping matrix and the second mapping matrix, and

wherein the column of the first mapping matrix is a first column element of the first mapping matrix.

2. The method of claim 1, wherein the VHT-SIG-A field includes a group identifier indicating whether a data unit including the data field is transmitted by a single-user transmission or a multi-user transmission.

3. The method of claim 2, wherein the VHT-SIG-B field includes a modulation and coding scheme (MCS) indicator, if the group identifier indicates the data unit is transmitted by a multi-user transmission.

4. The method of claim 2, wherein if the VHT-SIG-A field indicates that the data unit is transmitted by the single-user transmission, the VHT-SIG-B field is not decoded by the receiver.

5. A wireless apparatus in a wireless local area network, the wireless apparatus comprising:

transceiver transmitting and receiving radio signals; and

processor operably coupled to the transceiver and configured to;

transmit a very high throughput (VHT)-SIG-A field to a receiver,

transmit a very high throughput (VHT)-long training field (LTF) for multiple input multiple output (MIMO) channel estimation to the receiver,

transmit a VHT-SIG-B field to the receiver, and

transmit a data field to the receiver,

wherein the VHT-SIG-A field, the VHT-LTF, the VHT-SIG-B field and the data field are sequentially transmitted,

wherein the VHT-SIG-A field includes a spatial streams indicator indicating a number of spatial streams for transmitting the data field,

wherein the VHT-LTF is applied by a first mapping matrix and a second mapping matrix,

wherein the data field is applied by the second mapping matrix,

wherein the VHT-SIG-B field is applied by a column of the first mapping matrix and the second mapping matrix and is mapped to the spatial streams based on the applied first mapping matrix,

wherein the VHT-SIG-A field is not applied by any of the first mapping matrix and the second mapping matrix, and

wherein the column of the first mapping matrix is a first column element of the first mapping matrix.

6. The apparatus of claim 5, wherein the VHT-SIG-A field includes a group identifier indicating whether a data unit including the data field is transmitted by a single-user transmission or a multi-user transmission.

7. The apparatus of claim 6, wherein the VHT-SIG-B field includes a modulation and coding scheme (MCS) indicator, if the group identifier indicates the data unit is transmitted by a multi-user transmission.

8. The apparatus of claim 6, wherein if the VHT-SIG-A field indicates that the data unit is transmitted by the single-user transmission, the VHT-SIG-B field is not decoded by the receiver.