NGI中一种切换目标预测机制

基于统计与即时相结合的方法,设计了NGI中的一种切换目标预测机制.首先,采用统计预测,根据切换历史记录,建立模糊决策树,据此预测切换目标.如果预测到的目标有多个,则根据用户当前位置、运动方向和运动速率等即时信息以及平均呼叫持续时间进行即时预测,计算用户对每个预测到的目标的访问概率,选取该值最大的作为切换目标.仿真结果表明,同单一的统计预测机制和即时预测机制相比,该机制在不同速率下的预测命中率都较高,总体性能好.

A Handoff Target Prediction Scheme in NGI

Based on the combination of instant method with statistical method,a target prediction scheme for handoff in NGI is designed by use of statistical prediction and historical handoff record to form a fuzzy decision tree.If there exist several target cells predicted,an instant prediction scheme runs to compute the accessing probability of each and all predicted target cells in accordance to the user's current information such as position,moving speed/direction and average call duration,then the maximum addressing probability is picked out as the handoff target cell.Simulation results showed that the proposed scheme has higher hitting rates at different users' movement speeds in comparison with those schemes simply based on statistical prediction or instant prediction,with a better overall performance provided.