Trade-off between spectral and energy efficiency in THz frequency bands for 6G

The scientific community as well as companies in the telecommunications field are turning more and more towards 6G. One of the possibilities accepted by the community for 6G is the use of sub-THz bands (0.1 THz - 10 THz). These frequency bands are studied with great interest, since they would allow communication at very wide band (several GHz), at very high speeds and with low latency. On the other hand, communications at sub-THz frequencies raise ecological problems: the power consumed is high. This is what we study in this article. We seek to optimize the spectral efficiency while minimizing the energy consumption of the communication system. The optimization is performed by taking into account the power consumption of the power amplifier and the energy consumed by the Radio Frequency (RF) circuits. The consumption of the RF circuits is modeled by the sum of a static and a dynamic part. Particular attention is paid to the dynamic part and its impact on the compromise between energy consumption and spectral efficiency.