normally can't.
radar source should have a spec for on/off power ratio, that should be about 100dB. So no problem.
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And, from the time domain, the switch are very fast, it is about ns grade.
I remember I used Hittite switch.
In software, it must be waited the pulse rising edge or falling edge.
I am not SW engineer, so I don't know more details.
switching power supplies are more efficient than linear but generate emi interference to overcome this problem keep distance between power supply and practical circuit.
You should specify your radar type to get a useful answer. If your radar is a pulsed RF version, you can use a switched power supply if its switching frequency is well different from your PRF. If your radar is a Doppler type, switching supply spectrum may be different to filter from the useful signal spectrum.