Frame transmitting method and frame receiving method

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

receiving a second frame including bandwidth information of a second channel from a second device before transmitting a first frame, the second channel being selected from among a plurality of channels into which an entire channel width is divided;

transmitting the first frame including bandwidth information of a first channel directly to the second device, the first channel being selected from among the plurality of channels into which the entire channel width is divided and discontinuous channels capable of being selected as the first channel from among the plurality of channels; and

performing a direct communication with the second device through the first channel,

wherein a direct transmission is performed through a third channel between a third device and a fourth device when the direct communication with the second device through the first channel is performed, the third channel is determined by the third device using the bandwidth information included in the second frame and the bandwidth information included in the first frame, and the third channel is a part of the plurality of channels and the first and third channels have disjoint bandwidths, and

wherein each channel of the plurality of channels is a wireless channel, and

wherein the second channel has a bandwidth that includes the first channel and the third channel.

2. The method of claim 1 , wherein receiving the second frame includes receiving the second frame on the plurality of channels.

3. The method of claim 1 , wherein receiving the second frame includes receiving the second frame only on the second channel.

4. The method of claim 1 , wherein transmitting the first frame includes transmitting the first frame on the plurality of channels.

5. The method of claim 1 , wherein transmitting the first frame includes transmitting the first frame only on the first channel.

6. The method of claim 1 , further comprising matching an end time of a transmission through the first channel to an end time of the direct transmission through the third channel.

7. The method of claim 1 , further comprising, when the direct transmission through the third channel ends and a new transmission through the third channel starts while a transmission through the first channel is performed, aligning an end time of the transmission through the first channel to be matched to an end time of the new transmission through the third channel.

8. The method of claim 1 , further comprising:

setting a first network allocation vector (NAV) by a transmission through the first channel at the third device after the direct communication with the second device is completed; and

setting a second NAV by a transmission through the third channel.

9. The method of claim 8 , further comprising:

when any one of the first NAV and the second NAV is expired, acquiring a transmission opportunity (TXOP) through a channel of the expired NAV; and

aligning TXOP duration of a transmission through the channel of the expired NAV with TXOP duration of a channel of unexpired NAV.

10. The method of claim 1 , wherein the first frame includes a legacy short training field, a legacy long training field, a legacy signal field, and a data field of a legacy frame format, and

wherein the bandwidth information is allocated 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 of the legacy short training field, the legacy long training field, the legacy signal field and the data field.

11. The method of claim 10 , wherein the at least one field includes the data field.

12. The method of claim 11 , wherein the at least one field further includes the legacy signal field.

13. The method of claim 1 , wherein the first and second devices are both associated with a first Basic Service Set (BSS) and the third and fourth devices are both associated with a second BSS different from the first BSS.

14. The method of claim 1 , wherein the first, second, third, and fourth devices are all associated with a same Basic Service Set (BSS).

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

transmitting a second frame including bandwidth information of a second channel to a second device before receiving a first frame;

receiving the first frame including bandwidth information of a first channel directly from the second device, the first channel being selected from among a plurality of channels into which an entire channel width is divided and discontinuous channels capable of being selected as the first channel from among the plurality of channels; and

performing a direct communication with the second device through the first channel,

wherein a direct transmission is performed through a third channel between a third device and a fourth device when the direct communication with the second device through the first channel is performed, the third channel is a part of the plurality of channels and does not include the first channel, the third channel is determined by the third device using the bandwidth information included in the second frame and the bandwidth information included in the first frame, and the first and third channels have disjoint bandwidths, and

wherein each channel of the plurality of channels is a wireless channel, and

wherein the second channel has a bandwidth that includes the first channel and the third channel.

16. The method of claim 15 , wherein transmitting the second frame includes transmitting the second frame on the plurality of channels.

17. The method of claim 15 , wherein transmitting the second frame includes transmitting the second frame only on the second channel.

18. The method of claim 15 , wherein receiving the first frame includes receiving the first frame on the plurality of channels.

19. The method of claim 15 , wherein receiving the first frame includes receiving the first frame only on the first channel.

20. The method of claim 15 , wherein the first, second, third, and fourth devices are all associated with a same Basic Service Set (BSS).