FRAME TRANSMITTING METHOD AND FRAME RECEIVING METHOD

• US 20150296517A1
• Filed: 04/10/2015
• Published: 10/15/2015
• Est. Priority Date: 04/11/2014
• Status: Active Grant

• Current Assignee: Atlas Global Technologies LLC (Acacia Research Corporation)
• Original Assignee: Newracom Inc.
• Inventors: YU, Heejung, CHEONG, Minho, KWON, Hyoung Jin
• Granted Patent: US 9,712,342 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: H04B 7/04 using two or more spaced independent antennas
• CPC Class Codes: H04B 7/0452 Multi-user MIMO systems
• CPC Class Codes: H04L 25/0202 Channel estimation
• CPC Class Codes: H04L 25/03866 using scrambling
• CPC Class Codes: H04W 74/002 Transmission of channel access control information
• CPC Class Codes: H04W 84/12 WLAN [Wireless Local Area Networks]

Abstract

A method of transmitting a frame is provided by a device in a WLAN. The device sets as additional data subcarriers some of subcarriers which are not set as data subcarriers in at least part of fields included in a frame of a legacy frame format, and allocates information to the additional data subcarriers.

Claims

1. A method of transmitting a frame by a device in a wireless local area network (WLAN), the method comprising:

generating a legacy short training field, a legacy long training field, a legacy signal field, and a data field of a legacy frame format;

allocating predetermined information to additional data subcarriers that are some of subcarriers which are not set as data subcarriers at the legacy frame format, in at least one field among the legacy short training field, the legacy long training field, the legacy signal field, and the data field; and

transmitting a frame including the legacy short training field, the legacy long training field, the legacy signal field, the data field, and the predetermined information.

2. The method of claim 1, wherein the at least one field includes the data field.

3. The method of claim 2, wherein the at least one field further includes the legacy signal field.

4. The method of claim 1, wherein the additional data subcarriers include some of subcarriers that are used as guards in the legacy frame format.

5. The method of claim 4, wherein the additional data subcarriers include subcarriers whose indices −

28, −

27, 27, and 28 on a 20 MHz bandwidth basis.

6. The method of claim 1, wherein the additional data subcarriers on a symbol of a plurality of symbol included in the at least one field are used as a long training field for channel estimation.

7. The method of claim 1, wherein when M additional data subcarriers are used in each of N symbols of the at least one field, the predetermined information is allocated by a predetermined M×

N matrix pattern.

8. The method of claim 1, wherein the frame is a request to send (RTS) frame or a clear to send (CTS) frame.

9. The method of claim 8, wherein the predetermined information includes information on a bandwidth which the device uses.

10. The method of claim 1, wherein the frame further includes an indication indicating whether the frame is in a mode using an additional data subcarrier.

11. The method of claim 10, wherein a predetermined bit of the legacy signal field includes the indication.

12. The method of claim 10, wherein a predetermined bit of the first 7 bits in a scrambling sequence for scrambling the data field includes the indication.

13. The method of claim 10, wherein the data field includes a service field,

the first 7 bits of the service field corresponds to the first 7 bits of a scrambling sequence, and

a predetermined bit of the first 7 bits in the scrambling sequence includes the indication.

14. The method of claim 10, wherein the data field includes a service field, and

a predetermined bit of the eighth to sixteenth bits in the service field includes the indication.

15. A method of receiving a frame by a device in a wireless communication network, the method comprising:

receiving a frame of a legacy frame format including a legacy short training field, a legacy long training field, a legacy signal field, and a data field; and

acquiring information from additional data subcarriers that are set by some of subcarriers which are not set as data subcarriers at the legacy frame format, in at least one field among the legacy short training field, the legacy long training field, the legacy signal field, and the data field.

16. The method of claim 15, wherein the additional data subcarriers include some of subcarriers that are used as guards in the legacy frame format.

17. The method of claim 16, wherein the additional data subcarriers include subcarriers whose indices −

28, −

27, 27, and 28 on a 20 MHz bandwidth basis.

18. The method of claim 15, wherein the information includes information on a bandwidth which a device transmitting the frame uses.

19. The method of claim 15, further comprising determining whether the frame is in a mode using an additional data subcarrier, based on an indication included in a predetermined bit of the frame.

20. The method of claim 15, further comprising determining whether the frame is in a mode using an additional data subcarrier, by measuring a power of subcarriers that are not set as data subcarriers in the legacy frame format.