中文摘要：

复杂环境下导航接收机的连续可用性一直是卫星导航领域的研究重点.针对矢量跟踪环动态适应性不够和误差在通道间传播的问题,提出一种鲁棒全球导航卫星系统（GNSS）矢量跟踪环.基于各通道的伪距、伪距率和伪距加速度状态量构建扩展卡尔曼滤波器（EKF）,通过灵活设置过程噪声方差阵,实现跟踪通道的耦合与解耦;采用基于极大似然估计器（MLE）的鉴别器生成码延迟和载波频率偏差观测量;利用滤波值修正并预测伪距率来控制本地数控振荡器（NCO）,实现环路的闭合.仿真结果表明,本文设计的矢量跟踪环在保证环路相互辅助的基础上,避免了衰减通道误差在通道间的传播,可以对被遮挡信号保持稳定跟踪,鲁棒性优于传统矢量延迟频率锁定环.

英文摘要：

Reliable and continuous navigation over challenging environment is an important research focus in satellite navigation.Because the vector tracking loop has some limitations in dynamic environments and the errors spread among all the channels,this paper proposes a robust global navigation satellite system （GNSS） vector tracking loop.Firstly,the extended Kalman filter （EKF） is modeled with the states of pseudo range,pseudo range-ratio and pseudo range-acceleration errors of all the channels.The channels can be easily coupled and decoupled through adjusting the process noise covariance.Then,the code delay and Doppler shift errors are produced by the maximum likelihood estimator （MLE）-based discriminators.Lastly,the predicted pseudo range-ratios drive the local numerical control oscillator （NCO） to match the incoming signals and close the loop.Simulation results show that during the signal fading and blockage areas,the presented robust vector tracking loop can keep excellent tracking for all the channels and prevent the normal channels from being infected by the degraded ones,and provide a more robust tracking than traditional vector delay frequency lock loop.