Optimization of Decentralized Caching with Improved Coded Delivery Under Heterogeneous File Popularity

This paper considers the design and optimization of decentralized coded caching under heterogeneous file popularity. We propose a decentralized nested coded caching scheme (D-NCCS) that implements an improved nested coded delivery strategy to avoid using zero-padding, a common sub-optimal approach for simplifying the coded delivery under heterogeneous file popularity. We formulate a joint optimization problem to jointly optimize the cache placement and nested coded delivery strategies of the D-NCCS, and develop a successive approximation algorithm to solve the problem. Numerical results demonstrate the close to optimal performance of the optimized D-NCCS.