Computes the noise spatial coherence model for a set of frequencies. Two models are implemented: fully siotropic and 2d isotropic (more accurate in room acoustics since floor and weiling are more absorbant)
:param n_freq: number of frequency bin in the spatial coherence model
:param typ: model of spatial coherence ("3d_iso": 3d isotropic; "2d_iso": 2d isotropic)
:param fs: sample rate
:param c: speed of the sound
:param intermic dist: distance between the two microphones in the spatial coherence model