Optimal Caching Strategy for Coordinated Small-Cells With Limited Backhaul

We consider a coordinated small-cell network with band-limited backhaul, where each small-cell base-station has to fetch the requested content from the central unit (CU). Due to the limited backhaul, real-time traffic offloading from the CU may become highly constrained upon heavy data requests. To address this problem, in this letter, an edge caching technique with optimal cache placement is proposed to minimize transmission errors under limited backhaul. A matrix indicating the overall cache placement is optimized following appropriate problem formulation. We demonstrate the effectiveness of the proposed caching strategy through numerical studies. Results show that the proposed method outperforms the existing ones.