Radio frequency doubler

A radio frequency doubler, comprising:

• sources of a first transistor and a second transistor and a drain of a fifth transistor being connected to each other, and sources of a third transistor and a fourth transistor and a drain of a sixth transistor being connected to each other;
• a source of the fifth transistor and a source of the sixth transistor being connected to each other;
• gates of the first and fourth transistors and a gate of the fifth transistor being connected to each other via a first capacitor, and gates of the second and third transistors and a gate of the sixth transistor being connected to each other via a second capacitor;
• drains of the first transistor and the third transistor being connected to each other, drains of the second transistor and the fourth transistor being connected to each other, and a tuned circuit being connected to terminals connecting the drains of the first and third transistors and the drains of the second and fourth transistors, the tuned circuit resonating at a double frequency;
• and
• a gate terminal of the first transistor and a gate terminal of the second transistor being provided with a signal source of a radio frequency band for a differential input.