Multihop Caching-Aided Aided Coded Multicasting for the Next Generation of Cellular Networks
Abstract: The next generation of cellular networks deploying wireless distributed femtocaching infrastructure proposed by Golrezaei et al. is studied. By taking advantage of multihop communications in each cell, the number of required femtocaching helpers is significantly reduced. This reduction is achieved by using underutilized storage and communication capabilities in user terminal terminals, which results in reducing the deployment costs of distributed femtocaches. A multihop index coding technique is proposed to code the cached contents in helpers to achieve order-optimal optimal capacity gains. As an example, we consider a wireless cellular system m in which contents have a popularity distribution and demonstrate that our approach can replace many unicast communications with multicast communication. We will prove that simple heuristic linear index code algorithms based on graph coloring can achieve order-optimal optimal capacity under Zipfian content popularity distribution.