Delay-Aware Dynamic Resource Management for High-Speed Railway Wireless Communications

In this paper, we investigate the delay-aware dynamic resource management problem for multi- service transmission in high-speed railway wireless communications, with a focus on resource allocation among the services and power control along the time. By taking account of average delay requirements and power constraints, the considered problem is formulated into a stochastic optimization problem, rather than pursuing the traditional convex optimization means. Inspired by Lyapunov optimization theory, the intractable stochastic optimization problem is transformed into a tractable deterministic optimization problem, which is a mixed-integer resource management problem. By exploiting the specific problem structure, the mixed-integer resource management problem is equivalently transformed into a single variable problem, which can be effectively solved by the golden section search method with guaranteed global optimality. Finally, we propose a dynamic resource management algorithm to solve the original stochastic optimization problem. Simulation results show the advantage of the proposed dynamic algorithm and reveal that there exists a fundamental tradeoff between delay requirements and power consumption.

I. Introduction

For the last decade, high-speed railway (HSR) has attracted a lot of attentions as a fast and convenient public transportation system. With the continuous construction of HSR in recent years, the demand for mobile communication on high-speed trains is increasingly growing [1]. More and more services related with the railway control need to be transmitted between the train and the ground in order to guarantee the train moving safety. Meanwhile, the passengers have an increasingly high demand on wireless Internet services. To fulfill the high demand for wireless data transmission, the study on efficiency of HSR communications is critical.