Downlink Resource Sharing for D2D Communications in a Filtered OFDM System

The performance of Device-to-Device (D2D) communications in a cellular network depends on the resource sharing scheme between D2D links and cellular users. Existing research on resource sharing mainly focuses on power allocation under the condition that each D2D pair shares one cellular user's entire resources upon approval. Unlike conventional resource sharing schemes, this paper focuses on the low energy characteristics of the filtered OFDM signals in the guard band, and provides a novel resource sharing strategy which allows D2D pairs to share only part of one cellular user's resources. In the proposed approach, the base station allocates the resource blocks in the guard band to the D2D pairs first; if the allocated resource blocks can't meet the D2D communication requirement, the base station allocates part of the downlink resource blocks to the D2D users. The proposed scheme can further suppress the cellular-user-induced interference, and thereby improves the D2D capacity performance while guaranteeing the stability of cellular communications. Numerical results show that the proposed resource sharing strategy provides better D2D capacity performance.