  Current imaging observations of protoplanetary disks using ALMA primarily
focus on the sub-millimeter wavelength, leaving a gap in effective
observational approaches for centimeter-sized dust, which is crucial to the
issue of planet formation. The forthcoming SKA and ngVLA may rectify this
deficiency. In this paper, we employ multi-fluid hydrodynamic numerical
simulations and radiative transfer calculations to investigate the potential of
SKA1-Mid, ngVLA, and SKA2 for imaging protoplanetary disks at sub-cm/cm
wavelengths. We create mock images with ALMA/SKA/ngVLA at multi-wavelengths
based on the hydrodynamical simulation output, and test different sensitivity
and spatial resolutions. We discover that both SKA and ngVLA will serve as
excellent supplements to the existing observational range of ALMA, and their
high resolution enables them to image substructures in the disk's inner region
($\sim$ 5 au from the stellar). Our results indicate that SKA and ngVLA can be
utilized for more extended monitoring programs in the centimeter waveband.
While in the sub-centimeter range, ngVLA possesses the capability to produce
high-fidelity images within shorter observation times ($\sim$ 1 hour on source
time) than previous research, holding potential for future survey observations.
We also discuss for the first time the potential of SKA2 for observing
protoplanetary disks at a 0.7 cm wavelength.
