Doppler frequency shift observation of ionospheric high frequency echo is an important method for studying ionospheric disturbances.
电离层高频反射回波的多普勒频移观测是研究电离层扰动的一个重要方法。
2
The speed of moving-target was measured based on the principle of PD frequency shift, and the range of moving-target on the pulse-echo principle.
利用多普勒频移原理实现了运动目标速度测量，利用脉冲回波测距原理实现运动目标距离测量。
3
When there is faint Doppler echo in noise, the system output is intermittent chaotic, and the Doppler shift can be obtained accurately by calculating the interval of chaotic state.