[mikewarot]

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_...

[2rsf]

It also has simple power control, making sure that all phones are received at the same power on the receiving antenna. Overall OFDMA is magic, if you can put your hands on a spectrum analyzer with constellation diagram you will be amazed.