Method and device by which NAN terminal transmits NAN service discovery frame in wireless communication system

1. A method of transmitting a NAN (neighbor awareness networking) service discovery frame during a DW (discovery window) in a wireless communication system, the method performed by a NAN terminal and comprising:

determining a time that a packet is available for transmission of a first NAN service discovery frame;

starting a backoff counter for the first NAN service discovery frame at the determined time; and

transmitting the first NAN service discovery frame when countdown of the backoff counter for the first NAN service discovery frame is completed,

wherein the backoff counter for the first NAN service discovery frame is stopped while a backoff counter for a sync beacon frame is counting down if the sync beacon frame is transmitted during the DW.

2. The method of claim 1 , wherein the backoff counter for the first NAN service discovery frame is generated for each of a plurality of packets.

3. The method of claim 1 , wherein the determined time after transmission of the sync beacon frame is completed.

4. The method of claim 3 , wherein a time that a packet is available for transmission of a second NAN service discovery frame is after transmission of the first NAN service discovery frame is completed if a plurality of NAN service discovery frames are transmitted.

5. The method of claim 1 , wherein:

the backoff counter for the first NAN service discovery frame is started at TStartDW+HC*40*aSlotTime;

TStartDW corresponds to a start point of the DW;

HC corresponds to a hop counter; and

aSlotTime corresponds to a configured MAC (medium access control) value.

6. The method of claim 5 , wherein the backoff counter for the sync beacon frame corresponds to a value randomly selected from if the HC is greater than 0.

7. The method of claim 1 , wherein:

the backoff counter for the first NAN service discovery frame is started at TStartDW+(HCmax+1)*40*aSlotTime;

TStartDW corresponds to a start point of the DW;

HCmax corresponds to a largest hop counter in a cluster to which the NAN terminal belongs; and

aSlotTime corresponds to a configured MAC (medium access control) value.

8. The method of claim 1 , wherein:

the backoff counter for the sync beacon frame starts at [A+(HC−1)*B+HC*C, A+(HC*B)+(HC+1)*C] when a hop counter of the NAN terminal is greater than 0;

HC corresponds to the hop counter;

A corresponds to a value configured as a section maximum value or a maximum value +1 for configuring the backoff counter for the sync beacon frame when the HC is 0;

B corresponds to a section size value configured for the HC; and

C corresponds to a variable for securing a section for transmitting the first NAN service discovery frame in each of a plurality of sections.

9. The method of claim 8 , wherein the configured section size value corresponds to a value configured with a same interval or a value predetermined for the HC.

10. The method of claim 1 , wherein the backoff counter for the first NAN service discovery frame is resumed when the sync beacon frame is transmitted.

11. The method of claim 1 , wherein a status of the NAN terminal is master status.

12. A NAN (neighbor awareness networking) terminal transmitting a NAN service discovery frame during a DW (discovery window) in a wireless communication system, the NAN terminal comprising:

a transceiver configured to transmit radio signals; and

a processor connected to the transceiver and configured to:

determine a time that a packet is available for transmission of a first NAN service discovery frame;

start a backoff counter for the first NAN service discovery frame at the determined time; and

control the transceiver to transmit the first NAN service discovery frame when countdown of the backoff counter for the first NAN service discovery frame is completed,

wherein the backoff counter for the first NAN service discovery frame is stopped while a backoff counter for a sync beacon frame is counting down if the sync beacon frame is transmitted during the DW.

13. The NAN terminal of claim 12 , wherein the backoff counter for the first NAN service discovery frame is generated for each of a plurality of packets.

14. The NAN terminal of claim 12 , wherein the determined time is after transmission of the sync beacon frame is completed.

15. The NAN terminal of claim 12 , wherein:

the backoff counter for the first NAN service discovery frame is started at TStartDW+HC*40*aSlotTime;

TStartDW corresponds to a start point of the DW;

HC corresponds to a hop counter; and

aSlotTime corresponds to a configured MAC (medium access control) value.

16. The NAN terminal of claim 15 , wherein the backoff counter for the sync beacon frame corresponds to a value randomly selected from [0 31] if the HC is greater than 0.

17. The NAN terminal of claim 12 , wherein:

the backoff counter for the first NAN service discovery frame is started at TStartDW+(HCmax+1)*40*aSlotTime;

TStartDW corresponds to a start point of the DW;

HCmax corresponds to a largest hop counter in a cluster to which the NAN terminal belongs; and

aSlotTime corresponds to a configured MAC (medium access control) value.

18. The NAN terminal of claim 12 , wherein:

the backoff counter for the sync beacon frame starts at [A+(HC−1)*B+HC*C, A+(HC*B)+(HC+1)*C] when a hop counter of the NAN terminal is greater than 0;

HC corresponds to the hop counter;

A corresponds to a value configured as a section maximum value or a maximum value +1 for configuring the backoff counter for the sync beacon frame when the HC is 0;

B corresponds to a section size value configured for the HC; and

C corresponds to a variable for securing a section for transmitting the first NAN service discovery frame in each of a plurality of sections.

19. The NAN terminal of claim 12 , wherein the backoff counter for the first NAN service discovery frame is resumed when the sync beacon frame is transmitted.

20. The NAN terminal of claim 12 , wherein a status of the NAN terminal is master status.