“…Power amplifier (PA) is one of the most important components in Radio Remote Unit (RRU), its performance strongly influence the whole system performance in terms of bandwidth, output power, and efficiency. 1,2 The PA module contributes over 65% of the energy usage in RRU, to improve the efficiency of the PAs and meet the power consumption requirement of the system, several kinds of design method is proposed, such Class-E, [3][4][5] Class-J, 6,7 Class-F, [8][9][10] and Doherty. 11,12 Although the working principle of those methods is difference, they all follow the same principles that minimum the output harmonic energy and the heat loss of transistor.…”