Adaptive Power Control for D2D Communications in Downlink SWIPT Networks With Partial CSI

In this letter, we consider the device-to-device (D2D) communication in downlink cellular networks, where the cellular user (CU) both decodes information and harvests the energy. Unlike the conventional D2D communications, we figure out that it is possible for the D2D pair to communicate without degrading the performance of the CU. Based on this observation, D2D transmit power control schemes are proposed for D2D rate maximization subject to maintaining the CU performance. In a decentralized way, the proposed power control schemes are performed at the D2D transmitter (DT) with instantaneous channel state information (CSI) of only the link between the D2D pair. For performance analysis, an asymptotic upper bound is provided on the D2D rates of the proposed schemes. Numerical results confirm the effectiveness of the proposed schemes.