【摘要】 低廉的价格和恶劣的环境会导致传感器节点采样数据中存在误差和异常数据,所以有时候需要通过中位数查询来反映整个监测区域的平均水平.本文首先提出了基于等高直方图的中位数查询算法HMA,然后我们对其进行了扩展,提出了结合直方图与过滤器的HFMA算法,每个采样周期中只需要收集落在过滤器当中的数据并聚集数据的影响因子,基站根据收集的数据和影响因子聚集值计算出中位数.实验表明HFMA算法优于NAIVE算法和HMA算法,可以有效的节省能量开销,提高网络生命周期.更多还原

【Abstract】 Poor quality and harsh condition can result in faulty and outlier data in sampling data of sensor nodes.So we need median query to reflect average level of monitoring region.First,we put forward HMA algorithm.Second,we extend HMA algorithm and put forward HFMA algorithm.In HFMA,We only need collect data inside filter and aggregate influence coefficient during sampling period.Base station can compute median result according to the sample data inside filter and influence coefficient aggregation value.Experimental results have shown that HFMA outperforms Naive algorithm and HMA algorithm and can prolong the lifetime of sensor network.更多还原