1.4 GHz radio luminosity function of SFGs (blue circles) and radio-excess AGNs (red squares) in different redshift bins. For SFGs, the blue solid line represents the best-fit PLE model, which is the best model to describe the data in this work. For radio-excess AGNs, the red solid line represents the best-fit PDE model, which is the best model to describe the data. The magenta vertical dash-dotted line represents the turnover luminosity between the radio luminosity function of SFGs and radio-excess AGNs (see details in Sect. 5.4). The light blue circles show the results for SFGs from the VLA-COSMOS 3 GHz project (Novak et al. 2017), while the gold squares show the results for radio-AGNs from the VLA-COSMOS 3 GHz project (Smolčić et al. 2017a). The redshift bins in this work have different definitions than in Novak et al. (2017) and Smolčić et al. (2017a).