Abstarct: Device to device (D2D) communication and Energy harvesting (EH) are two of the technologies introduced in 5G of telecommunications, which has been developed to improve spectral efficiency and to extend the lifetime for users in wireless network. In this thesis, the effect of energy harvesting and power allocation taken into signals transmitted on the probability outage is evaluated. In fact, the outage probability for user equipment in relay network is investigated. Communication between two users in the network, can apply via a Two-way Relay (TWR) DAF capable with Energy harvesting, so that if relay is unable to decode one of the received signals, is sends it to AF. In addition, the relay is able to take/extract part of received signal power for its power supply, using the power splitting technique, to send the signals to destination. Finally, is investigated allocations of received energy to the signal transmitted in the relay and plot the outage probability for different parameter in network in order to study the effect of each parameter.