The thesis is divided into three main parts. In the first part we have discussed the characterization of the radio source emission in the high radio frequency band. The second part has been devoted to investigating the Sunyaev-Zel’dovich effect focussing on its observability and on theoretical predictions for proto-galaxies. Finally, in the third part we have dealt with radio sources as a CMB foreground, with special reference to the Planck mission.
