up-Doppler

例句：

1. 1. The up-Doppler radar is used to detect the movement of objects in the sky.
   上行多普勒雷达用于探测天空中物体的运动。
2. 2.In up-Doppler measurements, the frequency shifts with the velocity of the moving object.
   在上行多普勒测量中，频率随移动物体的速度变化。
3. 3.Up-Doppler signals are often used for tracking aircraft in flight.
   上行多普勒信号常用于跟踪飞行中的飞机。