https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theore... This theorem states that the theo

https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theorem https://en.wikipedia.org/wiki/Shannon%E2%80%93Hartley_theore... This theorem states that the theoretical maximum channel capacity ("bandwidth" as measured by bits per second) is dependent on analog bandwidth (the other "bandwidth" lol) and signal to noise ratio. Now that's the information theoretical maximum, but stuff like QAM as people mentioned, and other more advanced techniques like OFDM and "next layer" stuff like FEC can get you very close to the theoretical maximum.