positioning interval meaning in English

定位点间距

As to the poor performance of klobuchar ionospheric correction model , a new method using a constant scale factor is presented ; gps satellites with negative elevation angles are found in observations , therefore , they should be deleted at positioning to improve observation geometry and precision . with the respect to effects of initial values on positioning , iterative computations should be executed after getting direct solutions from gps equations when positioning intervals increase , especially longer than 5 seconds
针对klobuchar电离层改正模型精度较差的问题，提出了定常因子修正法；由于发现在观测数据中存在负仰角卫星而造成定位精度大大下降，本文提出在定位时应剔除负仰角卫星，从而改善观测几何，提高定位精度；鉴于初始值对定位有较大影响，本文指出随着定位时间间隔的增加，尤其是大于5秒后，应先用直接法求初值，然后再迭代计算。