Folks, the ether is analog.

Digital cell phones do not emit "square waves". Please kill that meme.

Digital signals are fed to modulators in the final stages of the radio. The modulators take analog signals and use a lot of sophisticated tricks to make the phase and timing of the output contain "information" that is then demodulated on the other end into a perfect bit stream. If you looked at a cell phone signal on an oscilloscope, you would see a block of "hash" or noise centered on the carrier or sub-carrier frequency. It is all analog over the air.

Look up "Shannon's Theorem", COFDM, 8-VSB or 256QAM if you want to know more (these are over the air and cable modulation techniques for HDTV).