GNSS接收机DCB短期时变特征分析和估计方法

Analysis and Estimation of DCB Short-Term Time-Varying Characteristics for GNSS Receiver

提出一种使用非差非组合精密单点定位(PPP)估计和分析接收机DCB短时时变特征的方法。首先利用非差非组合PPP得到包含接收机DCB的重构电离层参数估值;然后通过IGS电离层GIMs格网模型内插剥离各历元站星斜向电离层距离延迟;最后通过最小二乘约束得到各历元接收机DCB解。由于格网本身精度(2~8 TECU)和插值精度限制,解算出来的接收机DCB并不能真实反映其短期时变特征。为此,提出利用站间单差或者历元间差分的方法还原其真实的变化态势。实验结果表明,所提出的方法能够正确估计接收机DCB,并能真实还原其短期时变特征,具有良好的适用性。

A method for estimating and analyzing the short-term time-varying characteristics of receiver DCB using non-difference non-combination precise single-point positioning(PPP) is proposed. Firstly, the estimation of reconstructed ionospheric parameters including receiver DCB is obtained by un-difference un-combination PPP, then, the ionospheric distance delay of each pair of the station and satellite can be separated by interpolating the IGS ionospheric GIMs grid model, and the receiver DCB of each epoch is obtained by least square constraints. However, due to the limitation of grid accuracy(2~8 TECU) and interpolation accuracy, the calculated receiver DCB can not truly reflect its short-term time-varying characteristics. Therefore, the method of using single difference between two stations or epoch difference is proposed to restore its real short-term time-varying characteristics. The experimental results show that the proposed method can correctly estimate the receiver DCB, and can truly restore its short-term time-varying characteristics, and has good applicability.