According to an exemplary embodiment, when a collision occurs among D2D signals, a final priority may be determined by combining maximum transmission power level (e.g., Pmax) information in settings of a resource pool configured for a D2D discovery channel and a priority that is based on a channel mentioned in the first embodiment. The maximum transmission power information in the settings for the D2D discovery channel resource pool may be classified as three power levels, that is, maximum/medium/minimum level. Also, the D2D data transmission power may indicate a maximum power or a general open loop power control, based on a TPC command. Accordingly, D2D data transmission to which a maximum power is set may also be considered. Therefore, by taking into consideration a power level of each channel, a channel having a high power has a high priority. When maximum transmission power information of channels that collide are identical to each other, the final priority may be determined in an order of a discovery signal>SA>data according to the first embodiment. A D2D channel having the highest priority may be preferentially transmitted, and remaining channels may be dropped or transmitted through puncturing.

For example, when transmission of a D2D discovery signal (maximum power), a D2D SA signal (maximum power), and D2D data (medium power, open loop power control) occurs on a single carrier with respect to a single UE that executes D2D, a D2D data channel that has a medium power level is dropped first according to the above described method, and a D2D discovery signal is finally transmitted out of the D2D discovery signal and the D2D SA signal having the maximum power, based on a priority item of the corresponding channels.