Resource Allocation in Highly Dynamic Device-to-Device Communication: An Adaptive Set Multi-Cover Approach

Device-to-device (D2D) communication has recently gained much attention for its potential to boost the capacity of cellular systems. D2D enables direct communication between devices while bypassing a base station (BS), hence decreasing the load of BSs and increasing the network throughput via spatial reuse of radio resources. However, the cellular system is highly dynamic, an optimal allocation plan of radio resource to D2D links at one time point can easily become suboptimal when devices move. Thus, to maximize spatial reuse in cellular systems, it is crucial to update the resource allocation adaptively to reflect the current system status. In this paper, we develop the first adaptive solution framework to the dynamic resource problem for maximizing spatial reuse. At the core of the framework, we present the two algorithms for the adaptive set multicover problem with approximation ratio <inline-formula> <tex-math notation="LaTeX">$f$ </tex-math></inline-formula> and <inline-formula> <tex-math notation="LaTeX">$\log n$ </tex-math></inline-formula>, respectively, where <inline-formula> <tex-math notation="LaTeX">$f$ </tex-math></inline-formula> is the frequency of the most frequent element and <inline-formula> <tex-math notation="LaTeX">$n$ </tex-math></inline-formula> is the total number of elements. The experimental results not only show that our solutions have a significant improvement in running time, compared with optimal or approximated offline methods, but also demonstrate their good performance through the resource usage, network throughput, and other metrics.