WAAS系统下单频GPS用户电离层延迟改正新方法

A New Method on Ionospheric Delay Correction for Single Frequency GPS Users in WAAS

对于现有 WAAS等差分 GPS系统而言 ,在电离层活动激烈及系统不能正常发送或用户无法正常接收电离层延迟改正信息时 ,如何确保其所服务区域内单频 GPS用户的电离层延迟的实时改正效果 ,是需要进一步解决的问题。本文提出一种能够同时克服这些不足的单频GPS电离层延迟实时改正方案 。

At present，for WAAS(Wide-Area Augmentation Systems)，how to efficiently correct ionospheric delays in real time for single frequency GPS users is still an urgent problem which needs to be further researched and must be solved when it can not normally broadcast differential ionospheric delay corrections,when user can not receive them,or when ionosphere is anomalies because these abnormal phenomena can bring out severe effects on navigation performance of single frequency user in WAAS.In this paper,a scheme is presented which can efficiently solve the above problem,with the aid of a new design of robust recurrence technique on the basis of the efficient combination of the single frequency GPS observations in users and high precision differential ionospheric delay corrections from WAAS.Its effectiveness is verified with examples.This method can be easily used and accepted by single frequency users and WAAS because it does not need any new requirement on receiver hardware and the present total frame of ionospheric delays correction algorithm of WAAS and requires a little improvement on receiver software only.The precision analysis of this scheme is also discussed.