Individual Preference Aware Caching Policy Design in Wireless D2D Networks
share
Cache-aided wireless device-to-device (D2D) networks allow significant throughput increase, depending on the concentration of the popularity distribution of files. While many previous investigations assumed that all users have the same preference, this may not be true in practice. This work investigates whether and how the information about individual preferences can benefit such cache-aided D2D networks. Considering a clustered network, we derive a network utility that considers both the user distribution and channel fading effects, and formulate a utility optimization problem. This formulation can be used to optimize several important quantities, including throughput, energy efficiency (EE), and hit-rate, and solve different tradeoff problems. We provide designs of caching policies that solve the utility maximization problem with and without coordination between the devices, and prove that the coordinated design can obtain the stationary point under a mild assumption. Using simulations of practical setups, we show that by properly exploiting the diversity entailed by the individual preferences, performance can be improved significantly. Besides, different types of tradeoffs exist between different performance metrics, and they can be managed by means of proper caching policy and cooperation distance design.
READ FULL TEXT