Sweep with Negative Frequencies
In this example, the Chirp block outputs a chirp signal containing negative frequencies. The Time Scope displays the signal output in the time domain, and the Spectrum Analyzer displays the spectrogram in the frequency domain.
Set the Sweep time to
1.5, Initial frequency to
25, Target frequency to
0, and Target time equal to Sweep time. The output chirp of this example might not behave as you expect because the sweep contains negative frequencies between 1 and 1.5 seconds. The sweep reaches the Target frequency (0 Hz) at 1 second, then continues on its negative slope, taking on negative frequency values until it traverses one Sweep time (1.5 seconds).
Run the model to see the time domain output.