基于Hopfield模型改进射线描迹的对流层延迟估计

摘要

针对射线描迹法在估计对流层延迟方面受限于探空观测的问题,提出利用Hopfield模型改进射线描迹的对流层延迟估计方法.该方法利用Hopfield模型中的干、湿折射率计算公式,建立对流层大气折射指数剖面模型,并将其应用到射线描迹法改进中,克服探空观测的限制,扩大了射线描迹法的适用范围.选取国际GPS服务组织(IGS)中四个测站的气象数据,分别采用改进射线描迹模型和基于Neil映射函数(NMF)的Hopfield模型、Saastamoinen模型进行对流层延迟估计,计算结果表明,改进射线描迹模型的估计精度优于其他两种模型,为对流层延迟实时监测应用提供了新的方法.%The method of ray tracing on tropospheric slant delay estimation is restrained by air-sounding obser-vation.An improved ray tracing method combined with Hopfield mode was proposed in this paper.This method established tropospheric refractivity profile model,which used dry/wet refractivity formula in Hopfield model. It was introduced into ray tracing method to relieve the dependence on air-sounding data,which helped to expand the field of application.Then,meteorological data of four observation station from International GPS Service (IGS)was selected,and tropospheric slant delay based on the improved ray tracing,Neil Mapping Function (NMF)based Hopfeild model and Saastamoinen model were respectively calculated.The results showed that the improved ray tracing method was prior than other two mode for estimating tropospheric slant delay in precise.