Principle
Pulse-Doppler radar is based on the Doppler effect, where movement in range produces frequency shift on the signal reflected from the target.
Radial velocity is essential for pulse-Doppler radar operation. As the reflector moves between each transmit pulse, the returned signal has a phase difference or phase shift from pulse to pulse. This causes the reflector to produce Doppler modulation on the reflected signal.
Pulse-Doppler radars exploit this phenomenon to improve performance.
The amplitude of the successively returning pulse from the same scanned volume is:
- So
This allows the radar to separate the reflections from multiple objects located in the same volume of space by separating the objects using a spread spectrum to segregate different signals.
- where is the phase shift induced by range motion.
Read more about this topic: Pulse-Doppler Radar
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