基于IMU辅助的高动态GPS信号捕获算法

高动态环境存在较大的多普勒频移,传统的GPS信号捕获方法捕获时间较长。为了快速捕获到信号,提出将惯性测量单元(InertialMeasurementUnit,IMU)辅助与快速傅里叶变换(FFT)相结合的快速捕获算法。该算法通过外部IMU的位置、速度辅助,预先估算高动态载体产生的多普勒频移,缩小频率搜索范围;利用二维FFT方法同时搜索码相位和多普勒频率,降低计算复杂度,加快捕获速度。仿真结果表明该算法可以显著减少捕获时间,提高捕获性能。

The Algorithm of High-dynamic GPS Signal Acquisition Based on IMU

There exists a larger Doppler shift under the high dynamic circumstance.The traditional GPS signal acquisition algorithm takes comparatively long time.In order to capture signal quickly,a fast acquisition algorithm based on IMU and fast Fourier transform(FFT) is proposed.The Doppler shift of high dynamic aircraft is previously estimated with velocity and position information of IMU so that the Doppler frequency bin is reduced.It can decrease computational complexity and increase acquisition speed by estimat...