Deramp

a phase deramping function

In the deramp process, the principle of continuous radar with a linearly frequency-modulated wave is applied to a pulsed radar.

Deramp processing entails mixing (i.e., multiplying) the return signal with two sinusoidal carriers of frequency fc and then low-pass-filtering the two resulting signals.

The trick with full deramp processing is to mix the echo with a replica of the transmitted chirp signal rather than with a fixed frequency tone (figure 4).