Method for transmitting and receiving D2D signal in wireless communication system, and apparatus therefor
AssigneeLG Electronics Inc.
InventorsSeungmin Lee, Hanbyul Seo
Life of this patent
Estimating the term…
Abstract
The present invention relates to a method and an apparatus for transmitting a device-to-device synchronization signal (D2DSS) of a first terminal in a wireless communication system. Specifically, the present invention comprises the steps of: determining a D2DSS transmission-related intention of a first terminal; and, if the first terminal has the D2DSS transmission-related intention, transmitting a D2DSS to a second terminal, wherein the D2DSS is transmitted prior to a scheduling assignment period, if the first terminal has the D2DSS transmission-related intention.
Claims4
A method for transmitting a device-to-device synchronization signal (D2DSS) by a first user equipment (UE) that is out of coverage of a base station in a wireless communication system, the method comprising:
- determining, by the first UE, that no synchronization source exists in a predetermined area based on a measurement value not being equal to or higher than a threshold value in the predetermined area;
- transmitting, by the first UE based on the determination, the D2DSS in a subframe;
- and
- repeatedly transmitting, by the first UE, the D2DSS in a plurality of subframes within a first time period prior to a second time period for a scheduling assignment (SA) scheduling a D2D data channel,
- wherein repeatedly transmitting the D2DSS is performed regardless of whether the SA is transmitted or not within the second time period based on a predetermined condition being satisfied,
- wherein the predetermined condition comprises (i) a D2DSS transmission timer related to the first time period being configured for the first UE and (ii) the subframe being included within a third time period in which the SA is transmitted,
- wherein the plurality of subframes are periodically configured as a 40 ms period, and
- wherein the measurement value is related to a physical sidelink broadcast channel demodulation reference signal (PSBCH DMRS).
A first user equipment (UE), that is out of coverage of a base station, for transmitting a device-to-device synchronization signal (D2DSS) in a wireless communication system, the first UE comprising:
- a memory;
- and
- at least one processor operatively coupled with the memory,
- wherein the at least one processor is configured to:
- determine that no synchronization source exists in a predetermined area based on a measurement value not being equal to or higher than a threshold value in the predetermined area;
- transmit, based on the determination, the D2DSS in a subframe;
- and
- repeatedly transmit the D2DSS in a plurality of subframes within a first time period prior to a second time period for a scheduling assignment (SA) scheduling a D2D data channel,
- wherein repeatedly transmitting the D2DSS is performed regardless of whether the SA is transmitted or not within the second time period based on a predetermined condition being satisfied,
- wherein the predetermined condition comprises (i) a D2DSS transmission timer related to the first time period being configured for the first UE and (ii) the subframe being included within a third time period in which the SA is transmitted,
- wherein the plurality of subframes are periodically configured as a 40 ms period, and
- wherein the measurement value is related to a physical sidelink broadcast channel demodulation reference signal (PSBCH DMRS).
Dependencies are inferred from the claim text.