Learning electronics in school is nowhere near what you actually end up doing in the real world. Once you finish with school, you will more than likely start as a junior engineer learning the real ropes under a mentor. As for me, I'm not doing baseband or anything like that--I do what amounts to power supply IC's. Almost every circuit you come up with needs to have a way of being powered from a stable and clean voltage supply. This supply has to come from rectified AC or other sources that are often poorly controlled. The chips I do provide a clean, stable, DC voltage for power. Some of the ones I do are specially designed for low noise on top of that DC voltage since most RF amplifiers have zero ability to reject supply variations and noise shows up as unwanted sidebands that wreaks havoc on the signal-to-noise ratio.