A L-band high efficient power amplifier in CPW techniques

In this paper a L-band hybrid integrated amplifier in CPW techniques with high power added efficiency is presented. A new phenomenon was observed in the experiments. The experiments show that although different bias points at class A, class AB and class B were set only small differences of power added efficiencies were obtained. As high as 58% power added efficienciy was obtained if a formal class A operation was set. Because the cut-off regions of high efficient power amplifiers were removed it is believed that the linearity of this kind of amplifier is improved for certain types of modulation techniques which are sensitive to the nonlinearities of the cut-off regions. For heat dissipation a clip-chip technique is used as a heat sink in a coplanar enviroment.