电离层延迟模型改进研究

Improvement of Ionosphere Delay Model

由于电离层延迟会对卫星的定位精度产生很大的影响,传统的电离层延迟Klobuchar模型的预报精度不高,而且其对夜间电离层延迟以及对延迟峰值出现时刻的预报存在明显的不合理性。因此必须进行修正,根据实测电离层延迟数据的特点对传统的Klobuchar模型进行了改进,并利用非线性最小二乘迭代算法对两种模型进行参数拟合,采用拟合参数计算两种模型的拟合值。通过比较两种拟合值相对于实际测量值的精度,可以得出:改进模型比传统模型提高了电离层延迟预报的精度,并且改善了传统延迟模型预报中存在的不合理性。

Traditionally , the impact of Ionosphere delay on satellite orientation can＇t be ignored . Because Klobuehar model＇s forecast accuracy is not high, and the forecast of night and the appearing moment of the maximum delay is obviously unreasonable, so amendment is necessary . Based on the actual ionosphere delay , an improved Klobuchar model was proposed . Using Iterative non - linear least square algorithm , the fitting parameters were got to compute the fitting Ionosphere delay . By comparing the two fitting values ralative to the actual measurement accuracy, the simulation showed that the improved Klobuchar markedly increased the accuracy of the ionosphere delay forecast and reduced the irrationality in the prediction of ionosphere delay .