Fig. 5: Beat jamming.
a The received spectrum (blue) and the difference between the jammed signal and Alice’s signal (red) are shown, for four different values of Mallory’s single-tone frequency, νM. As Mallory’s frequency increases, the interference signal and beat signal location (shown with the arrow) on the spectrum increase as well. b Measured BER (red dots) as a function of the difference in frequency between Alice and Mallory (\({\nu }_{A}\,-\,{\nu }_{M}\)). The observed oscillatory behavior can be modeled (blue line) using a simple description of the SINR (Eq. 5) and the BER fit of Fig. 4. Here, we used Aa = 1, Am = 0.17 for the amplitudes, \({{{{{\rm{SINR}}}}}}\,=\,19\,{{{{{\rm{dB}}}}}}\) in the absence of interference, and \(T\,=\,0.8929\,{{{{{\rm{ns}}}}}}\), which corresponds to the experimental data rate \(B\,=\,1.12\,{{{{{\rm{Gbps}}}}}}\). In these measurements, Alice’s frequency is fixed at 197.5 GHz.
