Method for transmitting or receiving D2D signal in wireless communication system and device therefor
According to one embodiment of the present invention, a method by which a terminal for supporting device to device (D2D) communication relays a D2D signal comprises the steps of: transmitting, by the terminal, a D2D signal to be relayed to a neighboring terminal; and relaying a signal transmitted by the neighboring terminal, on the basis of the information on the D2D signal, wherein the information on the D2D signal includes information on D2D power, and the information on the D2D power can be determined by considering a reception power difference between D2D signals transmitted on mutually adjacent frequencies.
1. A method of relaying a device-to-device (D2D) signal by a relay user equipment (UE) supporting D2D communication, the method comprising:
transmitting information on the D2D signal to be relayed by the relay UE to a neighboring UE; and
relaying the D2D signal transmitted by the neighboring UE based on the information on the D2D signal,
wherein the information on the D2D signal comprises information on D2D power,
wherein the information on the D2D power is determined in consideration of a reception power difference between D2D signals transmitted on frequencies adjacent to each other,
wherein the information on D2D power is used to configure the neighboring UE to use a transmit power of the D2D signal differently based on whether the neighboring UE transmits the D2D signal to the relay UE or to another neighboring UE, and
wherein a maximum reception power level corresponds to maximum reception power permitted to a first D2D signal within a range of not causing a decoding failure of a second D2D signal having minimum reception power among the D2D signals transmitted on the frequencies adjacent to each other.
2. The method of claim 1 , wherein the information on the D2D power corresponds to the maximum reception power level of the D2D signal to be relayed by the relay UE.
3. The method of claim 1 , wherein the information on the D2D power is for reducing interference from reception power of a first D2D signal transmitted on a first frequency, to a second D2D signal transmitted on a second frequency.
4. The method of claim 3 , wherein the information on the D2D power comprises at least one of information on a resource of the first D2D signal interfering with the second D2D signal, information on a transmitter of the first D2D signal, and a power reduction value for the first D2D signal.
5. The method of claim 1 , wherein the information on the D2D signal further comprises a message type of the D2D signal to be relayed by the relay UE and
wherein the relay UE relays a D2D signal of a different message type with a low priority or does not relay the D2D signal of the different message type.
6. The method of claim 1 , wherein the information on the D2D signal further comprises information on a size of data capable of being relayed by the relay UE.
7. A relay user equipment (UE) supporting device-to-device (D2D) communication, comprising:
a transmitter to transmit information on a D2D signal to be relayed by the relay UE to a neighboring UE; and
a processor to relay the D2D signal transmitted by the neighboring UE based on the information on the D2D signal,
wherein the information on the D2D signal comprises information on D2D power,
wherein the information on the D2D power is determined in consideration of a reception power difference between D2D signals transmitted on frequencies adjacent to each other,
wherein the information on D2D power is used to configure the neighboring UE to use a transmit power of the D2D signal differently based on whether the neighboring UE transmits the D2D signal to the relay UE or to another neighboring UE, and
wherein a maximum reception power level corresponds to maximum reception power permitted to a first D2D signal within a range of not causing a decoding failure of a second D2D signal having minimum reception power among the D2D signals transmitted on the frequencies adjacent to each other.
8. A method of transmitting a device-to-device (D2D) signal by a user equipment (UE) supporting D2D communication, the method comprising:
receiving information on the D2D signal to be relayed by a relay UE from the relay UE; and
transmitting the D2D signal to the relay UE and the neighboring UE based on the information on the D2D signal,
wherein the information on the D2D signal comprises information on D2D power,
wherein the information on the D2D power is determined in consideration of a reception power difference between D2D signals transmitted on frequencies adjacent to each other,
wherein the information on D2D power is used to configure the UE to use a transmit power of the D2D signal differently based on whether the UE transmits the D2D signal to the relay UE or to the neighboring UE, and
wherein a maximum reception power level corresponds to maximum reception power permitted to a first D2D signal within a range of not causing a decoding failure of a second D2D signal having minimum reception power among the D2D signals transmitted on the frequencies adjacent to each other.
9. The method of claim 8 , wherein the information on the D2D power corresponds to the maximum reception power level of the D2D signal to be relayed by the relay UE.
10. The method of claim 8 , wherein the information on the D2D power is for reducing interference from reception power of a first D2D signal transmitted on a first frequency, to a second D2D signal transmitted on a second frequency.
11. The method of claim 8 , wherein the information on the D2D signal further comprises a message type of the D2D signal to be relayed by the relay UE and wherein the UE determines transmit power based on the message type.
12. The method of claim 8 , wherein the UE selects a transmit power parameter and a reference signal parameter to be used for transmitting the signal in consideration of whether or not the transmitted signal is relayed by the relay UE.