一种低仰角对流层折射修正的新方法

大气折射效应引起电波传播延迟和路径弯曲,测量数据对流层折射修正的精度直接影响到飞行目标轨(弹)道确定的精度。考虑到对流层折射修正的精度和效率以及5°以下低仰角数据传统修正方法具有较大的误差,通常不对测量数据进行实时对流层折射修正,这使得实时定位的精度受到较大影响。文中提出了一种基于光电传播几何路径迭代的对流层折射修正新方法,解决了修正精度和实时性不能兼顾的问题。经大量无人机校飞和载人航天工程外场实测数据验证,该算法能够实时有效地消除低仰角对流层折射偏差,对高仰角测量数据的对流层折射修正亦具有较高的精度。

A new method on tropospheric refraction correction at low elevation

Atmospheric refraction leads to radiowave propagation delay and path bending.The precision of radiowave refractive errors correction in troposphere of measurement data directly influences orbit determination accuracy of airborne targets.Traditional tropospheric refraction correction methods have low precision or low efficiency,especially at low observation elevation below 5 degrees.All above considered,realtime tropospheric refraction correction isn′t often adopted to measurement data,which brings great impact on accuracy of realtime orbit determination.A new fast and efficient tropospheric refraction correction iterative algorithm was designed and studied,which could be utilized in realtime data processing.Experimental results based on vast quantities of measured data in outfield verified the validity and effectiveness of the proposed method in eliminating tropospheric refractive error at low elevation.Meanwhile,a better correction precision could also be obtained at high elevation.