Radio halo luminosity function at ν_o = 1400 MHz (black lines) for clusters at redshift 0.1−0.2. The contributions from halos with ν_s in different frequency ranges are also shown: 1000 < ν_s < 1400 MHz (red lines), 1400 < ν_s < 2000 MHz (blue lines), 2000 < ν_s < 4000 MHz (magenta lines), and ν > 4000 MHz (green lines). The dashed lines correspond to the minimum detectable radio halo power (according to Eq. (9) with ξ₁ = 3, see text for details) for EMU + WODAN survey and for the NVSS (from left to right).