强跟踪滤波器在高动态GPS信号跟踪中的应用  

Strong tracking Kalman filter loop applied for high dynamic GPS signals

作　　者：王熙赢[1] 陈熙源[2] 

机构地区：[1]东南大学仪器科学与工程学院,南京210096 [2]东南大学微惯性仪表与先进导航技术教育部重点实验室,南京210096

出　　处：《东南大学学报（自然科学版）》2014年第5期946-951,共6页Journal of Southeast University：Natural Science Edition

基　　金：国家自然科学基金资助项目(50975049)

摘　　要：为解决在高动态环境下GPS接收机跟踪环路中频信号失锁的问题,提出了一种基于线性强跟踪卡尔曼滤波器(STKF)理论的GPS信号跟踪环路.此跟踪环路以码鉴相器和载波鉴相器输出作为观测量,利用线性强跟踪卡尔曼滤波器对高动态环境下的码相位误差、载波相位误差、多普勒频率误差以及多普勒频率变化率误差进行估计,并将估计结果反馈给跟踪环路的数控振荡器,从而产生准确的本地载波和本地码.仿真结果表明,在GPS信号载噪比为45 dBHz时,线性强跟踪卡尔曼滤波器跟踪环路在多普勒频率变化率为5.0 kHz/s时仍能可靠跟踪,而传统的基于PLL/DLL和环路滤波器的跟踪环路在1.8 kHz/s时已经失锁.A novel linear STKF（strong tracking Kalman filter）-based GPS （global positioning system）tracking-loop estimator is developed to resolve the losing lock problem of GPS IF （intermediate frequency）signal tracking loop in high dynamic environment.Code phase detector and Carrier wave phase detector are used as the observations of the STKF.The code phase errors,carrier phase errors, Doppler shift errors and the rate of change of Doppler shift errors are estimated with the STKF.The estimation results of the STKF are responded to the tracking-loop NCOs （numerically controlled oscillator）to generate accurate local carrier and local code.The simulation results indicate that,in the case that the carrier-to-noise ratio is 45 dBHz,the STKF tracking loop works well even if the change rate of Doppler shift reaches 5 .0 kHz/s,but the traditional tracking loop based on PLL （phase lock loop）/DLL （delay locked loop）and loop filters may lose lock at 1 .8 kHz/s.

关 键 词：卡尔曼滤波器 强跟踪卡尔曼滤波器 GPS 跟踪 高动态 

分 类 号：P228.4[天文地球—大地测量学与测量工程]