Abstract
In this paper, a modified implementation of the LINC concept (MILC) is proposed. It consists of allowing a mix of in-phase and conventional LINC decomposition in front of the amplifiers to enhance the combining efficiency and consequently the overall efficiency. Depending on the conduction angle of the amplifier, the type of the input signal and the linearity constraints, an optimal MILC operating point can be found that outperformance the LINC amplifier. Moreover, as shown mathematically and through simulations, this architecture is less sensitive to branch imbalance. Finally, simulations using realistic transistor models and experimental validation of the MILC system using class B amplifiers have been done and confirm the efficiency improvement offered by this new technique.
Keywords: LINC amplifier, power-added efficiency, linearity, constant amplitude modulation.