A system simulates a moving target for a radar system under test. The system includes a Doppler simulation circuit (DSC), coupled to an input, to apply a frequency shift to RF pulses received on an RF signal to simulate speed. A signal attenuator coupled to the DSC is to simulate signal attenuation due to propagation loss of the RF pulses in atmosphere. A pulse detection circuit is to detect time of receipt of the RF pulses, including a first time of receipt of a falling edge of a first RF pulse. An I/O controller updates a value of the frequency shift for the DSC and of the signal attenuation for the signal attenuator during a time period between the first RF pulse and one of a second RF pulse or a second time at which the second RF pulse should have been received in case of a missing pulse.