长期演进项目中移动终端节能机制的性能优化

Performance Optimization of the Energy-saving Strategy for Mobile Terminals in Long Term Evolution Project

为了对长期演进项目LTE(Long Term Evolution)中引入的节能机制进行系统性能分析与参数优化,针对基于活动状态下的非连续接收机制DRX(Discontinuous Reception),考虑移动终端与基站之间的多个逻辑信道,建立一个多重同步休假排队模型.采用离散时间方法构造状态转移概率矩阵.基于系统的稳态分析结果,进行能量节省率,系统阻塞率和数据帧响应延迟等指标的性能研究.数值实验的结果表明,不同的性能指标之间存在着折中关系.通过建立利润函数,给出逻辑信道个数,休眠间隔及逻辑信道传输率等系统参数的优化设置方案.

In order to evaluate the system performance and optimize the system parameters for the energy saving strategy introduced in the LTE （ Long Term Evolution }, considering multiple logical channels between the mobile terminal and the base station, a queueing model with multiple synchronization vacations is built to capture the active DRX （Discontinuous Reception}. By using the method of a discrete-time queue, the state transition probability matrix is constructed. Following the system analysis results in steady-state, the performance measures in terms of the energy saving ratio, the system blocking ratio and the average delay of data frames are investi- gated. Numerical results with analysis show that there is a trade-off between different system measures. By constructing a profit func- tion, the number of the logical channel, the time length of the sleep period and the channel transmission rate are optimized.