论文标题
设备到设备缓存系统的移动性感知内容放置
Mobility-Aware Content Placement for Device-to-Device Caching Systems
论文作者
论文摘要
用户移动性对D2D缓存网络中最佳内容放置有很大影响。由于典型的用户可以传达留在典型用户D2D通信区域的相邻用户，因此应根据用户移动性更改最佳内容放置。在考虑到传入和传出用户的随机性下，我们制定了一个优化问题，以最大程度地减少BS的平均数据负载。事实证明，BS的平均数据负载最小化可以转化为具有矩阵约束的单调性函数的最大化，为此，贪婪的算法可以找到近乎最佳的解决方案。此外，当相邻用户的动作快速时，最佳内容放置以封闭形式得出，并通过合理的近似和放松的帮助。在高移动性方案中，最佳内容放置显示可缓解最流行的内容。
User mobility has a large effect on optimal content placement in D2D caching networks. Since a typical user can communicate neighboring users who stay in the D2D communication area of the typical user, the optimal content placement should be changed according to the user mobility. Under consideration of randomness of incoming and outgoing users, we formulate an optimization problem to minimize the average data load of a BS. It is proved that minimization of the average data load of a BS can be transformed to maximization of a monotonic submodular function with a matroid constraint, for which a greedy algorithm can find near-optimal solutions. Moreover, when motions of neighboring users are rapid, the optimal content placement is derived in closed-form, aided by reasonable approximation and relaxation. In the high mobility regime, the optimal content placement is shown to cache partial amounts of the most popular contents.
