  A wide-frequency radio study of Active Galactic Nuclei (AGN) is crucial to
evaluate the intervening radiative mechanisms responsible for the observed
emission and relate them with the underlying accretion physics. We present wide
frequency (5-45 GHz), high-sensitivity (few microJy/beam), (sub)-kpc JVLA
observations of a sample of 30 nearby (0.003 < z < 0.3) AGN detected by
INTEGRAL/IBIS at hard-X-ray. We find a high detection fraction of radio
emission at all frequencies, i.e. > 95 per cent at 5, 10 and 15 GHz and > 80
per cent at 22 and 45 GHz. Two sources out of 30 remain undetected at our high
sensitivities. The nuclear radio morphology is predominantly compact, sometimes
accompanied by extended jet-like structures, or more complex features. The
radio Spectral Energy Distributions (SEDs) of the radio cores appear either as
a single or as a broken power-law, a minority of them exhibits a peaked
component. The spectral slopes are either flat/inverted or steep, up to a
break/peak or over the whole range. The sample mean SED shows a flat slope up
to 15 GHz which steepens between 15 and 22 GHz and becomes again flat above 22
GHz. Significant radio-X-ray correlations are observed at all frequencies.
About half of the sample features extended emission, clearly resolved by the
JVLA, indicating low-power jets or large scale outflows. The unresolved cores,
which often dominate the radio power, may be of jet, outflow, and/or coronal
origin, depending on the observed frequency.
