aspcore.fouriertransform.czt_unit_circle

aspcore.fouriertransform.czt_unit_circle(time_sig, M, w_angle, a_angle)

Chirp-z transform on the unit circle

Can be viewed as a special case of the chirp z transform, where both a and w are on the unit circle. This is a generalization of the DFT, where the frequency bins do not necessarily cover the whole unit circle.

Parameters:

• time_sig (np.ndarray of shape (..., N)) – The time signal to be transformed. The transform is applied to the last axis

• a_angle (float) – The starting point for the chirp z transform. The value a in the chirp z transform is a complex number defined as exp(2j * pi * a_angle).

• w_angle (float) – The base for the frequency bins. The value w in the chirp z transform is a complex number defined as exp(2j * pi * w_angle).