Current Mode Outphasing Power Amplifier

In this work, we present a mixed mode outphasing power amplifier, where the devices operate constantly as current sources. While the traditional theory considers two ideal voltage sources driving the outphasing combiner, in this novel approach, two ideal current sources are used instead. Nonetheless, it is proved that a similar performance can be achieved, showing that this design methodology is viable. Moreover, since the combiner is now being current driven, there is no need to saturate the devices to obtain the outphasing characteristic, with consequent advantages on the achievable linearity and possibly on the PAE, when the gain is limited. The proposed PA architecture was validated with an implementation using GaN HEMT devices in class B, which achieved 50% drain efficiency at the 6dB back-off region.