comnum.fm_preemphasis

comnum.fm_preemphasis(x, fs, *, tau_s=5e-05)

The pre-emphasis of the message x, the exact inverse of fm_deemphasis() (the FIR (x[n] - a x[n-1]) / (1 - a)).

Parameters:

• x (array_like) – the real message.

• fs (float) – the sampling rate (Hz).

• tau_s (float) – the time constant (s).

Returns:

the pre-emphasised message (float64).

Return type:

numpy.ndarray

Raises:

ValueError – for a time constant or a rate that is not positive.