All-sky number distribution of radio halos within z < 0.6 as a function of the radio flux at 1.4 GHz as expected in the EMU+WODAN surveys (blue upper lines). For comparison, in the same figure, the expected distribution of radio halos in the redshift range 0.044 < z < 0.2, compared with that observed in the NVSS (black lines and filled dots) and in the redshift range 0.2 < z < 0.32 compared with that observed in the “GMRT RH Survey” (red lines and open dots) are also reported. The blue dashed line shows the distribution of turbulent generated halos.