一种基于扩展Kalman滤波器的载波跟踪环  

The Design of Carrier Tracking Loop Based on Extended Kalman Filter

作　　者：许静文[1] 王宇[1] 

机构地区：[1]中国空间技术研究院西安分院,西安710000

出　　处：《空间电子技术》2015年第4期54-57,共4页Space Electronic Technology

摘　　要：目前,低轨卫星接收机通常工作在高动态低信噪比环境下,为了适应输入信号的大的多普勒动态,载波跟踪环路需要增加环路带宽,而在低信噪比情况下时,增加环路带宽导致进入到环路的噪声增加,环路失锁概率增大。文章给出一种在高动态低信噪比环境下的扩展Kalman滤波器(EKF)的载波跟踪环。该环路不仅可以自适应的改变环路带宽,并且利用积分-清零滤波器的输出直接作为EKF的观测向量,避免使用鉴相器带来信噪比的损失。Typically LEO satellite receivers typically work at low SNR and high dynamic environment, in order to adapt to the dynamic Doppler of the input signal, the carrier tracking loop in satellite receivers needs to increase the loop band- width, while in the low SNR environment , increasing the loop bandwidth results in more noise into the loop and moreover in- creases the probability of loss of lock. This paper presents a new kind of extended Kalman filter （EKF） carrier tracking loop working at the low SNRand high dynamic environment. This loop can not only change adaptively the loop bandwidth, and but also use directly the output of the integral-clears filter as the observation vector of EKF, avoiding the loss using the phase detector.

关 键 词：载波跟踪环 扩展Kalman滤波器(EKF) 高动态 低信噪比 

分 类 号：TN916.92[电子电信—通信与信息系统]