MIMU辅助旋转弹丸GPS接收机跟踪环路设计

Design of Rotary Projectile GPS Receiver's Tracking Loop Aided by MIMU

在GPS导航定位系统中,多普勒频移直接影响接收机的跟踪性能.为了克服多普勒频移的影响,对高速旋转的弹载单天线GPS接收机跟踪环路进行了研究.分析了弹丸旋转产生的复杂多普勒频移的影响因素,给出了多普勒频移的数学模型,提出采用MIMU估计多普勒频移的方法设计二阶载波跟踪环路,建立了环路的模型,并对环路的跟踪性能进行了MATLAB仿真.结果表明:MIMU辅助的跟踪环路与无辅助的跟踪环路比较,带宽窄,能有效地抑制噪声干扰,较好地实现了对旋转信号的跟踪.

In GPS navigation and positioning systems, Doppler frequency shift is the key problems that degrade the tracking performance of the receiver. To overcome the influence of Doppler shift, the tracking loop of a single antenna GPS receiver mounted on high speed rotating missiles was studied. The factors of complex Doppler frequency shift produced by rotation were analyzed and the mathematical model of Doppler shift was established. A method that designing second order carrier tracking loop by MIMU assisted Doppler frequency estimation was proposed, the model of tracking loop was established, and the tracking performance of loop was simulated in MATLAB environment. Simulation results show that, comparison to non-aided tracking loop, the MIMU-aided tracking loop can effectively restrain noise and realize the rotation signal tracking with narrow bandwidth.