Method for transferring data in wireless communication system that supports device-to-device communication, and apparatus therefor

Patent metadata

Field	Value
Publication number	US-2018146478-A1
Application number	US-201515572736-A
Country	US
Kind code	A1
Filing date	Oct 26, 2015
Priority date	May 15, 2015
Publication date	May 24, 2018
Grant date	—

Abstract

Disclosed are a method for transferring data in a wireless communication system that supports device-to-device communication, and an apparatus therefor. Specifically, a method for performing, by a device, data transfer in a wireless communication system that supports device-to-device communication, comprises the steps of: broadcasting, at a first sub-carrier, a ready-to-forward (RTF) signal for advertising that the device holds data to transfer; receiving, at a second sub-carrier, a forward-request (FR) signal for requesting transfer of the data from another device; and broadcasting the data after a predetermined time, wherein the first sub-carrier and the second sub-carrier are determined on the basis of sequence numbers of the data, respectively.

First claim

1 . A method for a user equipment (UE) to perform data transfer in a wireless communication system that supports device-to-device communication, the method comprising:
broadcasting an Ready-To-Forward (RTF) signal on a first sub-carrier for advertising that the UE holds data to transfer; receiving an Forward-Request (FR) signal on a second sub-carrier for requesting transfer of the data from another UE; and broadcasting the data after a predetermined time, wherein the first sub-carrier and the second sub-carrier are determined on the basis of sequence numbers of the data, respectively.

2 . The method of claim 1 , wherein the predetermined time is determined on the basis of received strength of an FR signal for the data.

3 . The method of claim 1 , wherein, when the UE receives an RTF signal for the data from another node for the predetermined time period on the first sub-carrier, transfer of the data is cancelled.

4 . The method of claim 3 , wherein, when the UE receives an FR signal for the data from another node for the predetermined time period on the second sub-carrier, transfer of the data is rescheduled.

5 . The method of claim 1 , wherein the entire sub-carriers in system bandwidth are divided into a first sub-carrier group for RTF signal transmission and a second sub-carrier group for FR signal transmission; and
the first sub-carrier is determined from the first sub-carrier group, and the second sub-carrier is determined from the second sub-carrier group.

6 . The method of claim 1 , when the UE receives an RTF signal for the data from another UE, further comprising
broadcasting an FR signal for the data on the second sub-carrier; and receiving the data.

7 . The method of claim 6 , wherein, when the UE receives an RTF signal for the data from another UE, a sequence number of the data is added to a data request list of the UE.

8 . The method of claim 7 , wherein, when the UE receives the data or does not receive the data for a predetermined time period, the sequence number of the data is removed from the data request list.

9 . The method of claim 6 , wherein, when the UE receives the data, the sequence number of the data is added to a data transfer list of the UE.

10 . The method of claim 9 , wherein a sequence number of the data is removed from the data transfer list after a predetermined time period.

11 . The method of claim 6 , wherein, when the UE does not receive the data for a predetermined time period after transmitting the FR signal for the data, the FR signal for the data is re-broadcasted.

12 . The method of claim 11 , wherein, when the FR signal is re-broadcasted more than a predetermined number of times, reception of the data is given up.

13 . A user equipment (UE) performing data transfer in a wireless communication system that supports device-to-device communication, the UE comprising:
an Radio Frequency (RF) unit for transmitting and receiving a radio signal; and a processor controlling the RF unit, wherein the processor is configured to broadcast an Ready-To-Forward (RTF) signal on a first sub-carrier for advertising that the UE holds data to transfer; to receive an Forward-Request (FR) signal on a second sub-carrier for requesting transfer of the data from another UE; and to broadcast the data after a predetermined time, wherein the first sub-carrier and the second sub-carrier are determined on the basis of sequence numbers of the data, respectively.

Assignees

• Lg Electronics Inc
• Seoul Nat Univ R&Db Foundation

Inventors

• Kim Hakseong
• Kang Daeho
• Bahk Saewoong
• Jeong Seungbeom
• Joo Changhee

Classifications

• H04W72/535

  based on resource usage policies · CPC title

• H04W72/23

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04W72/30

  Resource management for broadcast services · CPC title

• H04W76/14

  Direct-mode setup · CPC title

• H04W4/70

  Services for machine-to-machine communication [M2M] or machine type communication [MTC] · CPC title