• target ber modulation selection
• tbms
• terahertz
• thz
• power loading
• bit loading
• ber constraint
• power constraint
• direct sequence spread spectrum
• dsss
• mercury waterfilling
• iterative waterfilling
• waterfillling

After explaining the most important and up-to-date applications in the THz band, some of the challenges in this high frequency range such as the high Free Space Loss (FSL) and the Molecular Absorption (MA) are introduced. It follows the need of a fresh a new power and bit loading strategy to efficiently allocate the TX power and choose the modulations on each subcarrier under some power and ber constraints. Hence the Target Ber Modulation Selection (TBMS) algorithm is proposed and compared to other recent and efficient algorithms to show its valuable performances. Among the innovations the TBMS brings, we have the possibility of choosing an arbitrary modulation set and the availability of a Direct Sequence Spread Spectrum (DSSS) technique on low Signal to Noise Ratio (SNR) subcarriers.