It took a lot of Wikipedia reading, but I finally got to OFDMA[1], which apparently is used by my 4G phone to talk to the world. I had no idea it just kept spewing RF at all times. Though, it will be transmitting more or less signal depending on how many subchannels it is using.

There will be experiments with an RF sniffer later when I get to my friends repair shop.

[1] https://en.wikipedia.org/wiki/Orthogonal_frequency-division_...