中文摘要：

针对切换业务在高速铁路通信系统中比较容易掉线的问题，提出一种基于优先级的接纳控制机制，联合利用自适应资源预留算法与基于弹簧的资源抢占模型，以保障系统切换业务掉线率（HSDP）需求．自适应资源预留算法可以根据切换业务通话量强度自适应地为切换业务预留带宽资源．在最小化资源抢占对现有业务影响的条件下，基于弹簧的资源抢占模型可以确保切换业务从现有可变速率业务中合理地抢占带宽资源，以进一步改善HSDP性能．仿真结果表明，该机制可以有效提升HSDP性能，同时保持令人满意的新业务阻塞率性能．

英文摘要：

For the problem of handoff service in high-speed railway communication （HSRC） systems prone to drop, a priority-based admission control （PB-AC） scheme is proposed, where adaptive resource reservation algorithm and spring-based resource preemption model are jointly adopted to guarantee handoff service dropping probability （HSDP） requirement. The adaptive resource reservation algorithm can dy- namically reserve bandwidth resource for handoff service according to their traffic intensity. Under the condition of minimizing the influence of resource preemption on on-going service, the spring-based re- source preemption model can enable handoff service to preempt bandwidth resource from on-going vary bit rate service to further improve HSDP performance. Simulation results show that the proposed PB-AC scheme can effectively improve HSDP performance while maintaining desirable new service blocking prob- ability performance.