Energy-Efficient Power Allocation in Cloud Radio Access Network of High-Speed Railway

Abstract

To meet the increasing demand of high-data-rate services of high-speed railway (HSR) passengers, cloud radio access network (C-RAN) is a promising technique in mobile communication system of HSR. In this paper, we focus on the energy-efficient power allocation problem for providing the high- data- rate services in HSR scenario. Based on the predicted path loss characteristic of HSR, the power allocation is formulated as a non-linear fractional programming problem. The service pro- cessing delay of baseband unit (BBU) pool and radio transmission delay at radio remote units (RRUs) are considered in the services transmission delay constraint. The formulated problem is a non- convex problem, an equivalent convex problem is reformulated firstly, and then propose an iterative algorithm to obtain the optimal power allocation solution. Furthermore, we analyze the effect of small-scale fading on energy-efficiency (EE) performance of the proposed power allocation scheme. Simulation results confirm that the proposed energy-efficient power allocation policy can meet the QoS of passengers and obtain the optimal EE performance.