Fig. 1: Data–rate limits versus carrier frequency for three line-of-sight link distances (d = 10 m, 100 m, and 1 km) assuming a 10% fractional bandwidth.
From: Sub-THz communication systems: pushing the capabilities of silicon
The solid, dashed, and dash-dot black curves are the Shannon-capacity ceilings \({C}_{\max }(f,d)\), while the light--tan area above the 10 m envelope marks the theoretically non--feasible region. Straight colored lines (Binary Phase Shift Keying (BPSK)–256 Quadrature Amplitude Modulated (QAM) \({\eta }_{{{\rm{mod}}}}=\{1,2,4,6,8\}\,{{\rm{bit}}}\,{{{\rm{s}}}}^{-1}\,{{{\rm{Hz}}}}^{-1}\)) show nominal raw data-rates. All calculations assume transmitted power of 20 dBm, transmit and receive antenna gain of 15 dBi each, and a receiver noise figure that rises linearly from 5 dB at 10 GHz to 20 dB at 300 GHz and remains flat beyond. Vertical dashed lines delineate two spectral windows: below half of the maximum frequency of power gain (fmax/2) (blue, encompassing the D-band) and above fmax/2 (primary focus of this work).
