Optimization of Mobile Video Transmission in the High-Speed Rail Environment

With the rapid development of high-speed rail (HSR) in the world, the demand for providing multimedia services (especially video-related applications) to passengers is ever increasing. The characteristics of radio channel in the HSR environment are adverse to high-quality mobile video transmission. In this work, to improve the quality of experience (QoE) for passengers on the high-speed train, a cognitive broadband wireless communication system is proposed. By employing a radio environment map (REM)-based cognitive wireless gateway, both high penetration loss and frequent group handover are avoided, which can significantly improve the QoE for mobile video transmission in the HSR environment. A handover algorithm aiming to enable reliable video transmission and QoE-driven handover is proposed. The results show that the proposed handover algorithm can gain more utility than the traditional algorithm and also reduce the number of handovers. Scenarios with equal weights and unequal weights for passengers are considered. Compared to the equal-weight scenario, higher utility can be obtained under the unequal-weight scenario.