Band-reconfigurable and load-adaptive power amplifier

An electronic circuit comprising an input matching network, a fixed output matching network, a transistor, and a tunable resonator, the transistor comprising:

• a gate connected to the input matching network;
• a source connected to ground;
• and a drain directly connected to an input of the tunable resonator;
• and the tunable resonator comprising:
• a varactor
• and an inductor connected in series to the varactor;
• and an output of the tunable resonator being connected to an input of the fixed output matching network;
• and
• wherein the tunable resonator further comprises
• at least one pair of varactor elements comprising,
• a first pair of varactor elements connected in series with an anode of one varactor element in the first pair being connected to an input of the varactor, a cathode of the one varactor element in the first pair being connected to a cathode of the other varactor element in the first pair, and an anode of the other varactor element in the first pair being connected to an output of the varactor;
• and
• wherein the fixed output matching network further comprises,
• at least one shunt open-stub connected to the output of the inductor in the tunable resonator;
• and
• at least one transmission line connected to the at least one shunt open-stub, the at least one transmission line being configured to be connected to an output load.