This is a bit off. Consider it rather like this: you can transmit a sine wave of varying phase and/or amplitude. With a single transmitter and no multi-path interference, each receiver sees the exact wave, plus some noise. Shannon's paper defines the limits on what you can transfer.
Now consider when you have multiple coordinated transmitters transmitting with different phases and amplitudes. Each receiver receives the sum of these functions at a relative offset equal to the varying distances, so will decode as a different symbol.
That's the simplest interference pattern you'll see. It's obvious to see that the wave a receiver gets will be dependent on location (e.g. notice the bands of 180 degree flipped phase). As a thought experiment you could imagine varying the phase and amplitude of the two transmitters such that receivers in 2 different places would see either similar, or different waveforms. There is almost certainly a limit to how many users you could support with N transmitters, but with good enough math and feedback, it's potentially fairly high, which is what these guys claim they can do.
Now consider when you have multiple coordinated transmitters transmitting with different phases and amplitudes. Each receiver receives the sum of these functions at a relative offset equal to the varying distances, so will decode as a different symbol.
Visual aid:
http://en.wikipedia.org/wiki/File:Two_sources_interference.g...
That's the simplest interference pattern you'll see. It's obvious to see that the wave a receiver gets will be dependent on location (e.g. notice the bands of 180 degree flipped phase). As a thought experiment you could imagine varying the phase and amplitude of the two transmitters such that receivers in 2 different places would see either similar, or different waveforms. There is almost certainly a limit to how many users you could support with N transmitters, but with good enough math and feedback, it's potentially fairly high, which is what these guys claim they can do.