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bps/hz measurements in TFA are bullshit without noise figures. Per Shannon-Hartley theorem, spectral density depends on the Bandwidth of the channel (assume infinite for free air) and noise. So what is the noise? of course DVB-T (Digital TV) has low bps/hz, the antenna is tens of KM away and there is a lot of noise! the experiment used two antennas located 1 meter away, almost zero noise. EDIT: You might as well cite the spectral density of the voyager II spacecraft onboard antenna. Hint: It's very very low.

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