“…Most of these solutions, e.g. [2] [3], perform a transformation of high Peak to Average Power Ratio (PAPR) signals, issued of complex modulations such as OFDM, into constant envelope ones. The motivation of this approach is that constant envelop e signals could be efficiently amplified using a switching mode power amplifier, such as class E [4], which could, theoretically, attain 100% drain efficiency.…”