New Constructions of D2D Placement Delivery Arrays

Coded caching is an effective solution to mitigate congestion in wireless networks, which can be extended to device-to-device (D2D) networks. D2D placement delivery array (DPDA) is a significance tool to describe the coded caching scheme in D2D networks. In this letter, we propose three methods to construct DPDAs directly and also obtain a class of new DPDAs from known PDAs. Compared with some known schemes, the schemes generated by new DPDAs show good performance in the packet number.