This paper presents envelope elimination and restoration (EER) architecture specifications in the case of orthogonal frequency division multiplex C band transmission. A key point is the recombination of envelope and phase information by supply modulation of the power amplifier (PA). Imperfections, such as time mismatch and phase noise can reduce the performances of the transmission. Compression and conversion effects when supply modulating the PA are introduced in this paper with the simulation of a class power amplifier. This amplifier was designed under HP-ADS using a nonlinear Mesfet model. Results are reported in terms of error vector measurement and spectrum for two different numbers of sub-carriers 32 and 128 in 16-QAM and 64-QAM cases. Index Terms—Class , envelope elimination and restoration (EER), orthogonal frequency division multiplex (OFDM).