Abstract: A matching network and method for matching a source impedance to a load impedance is provided. A bias feed microstrip structure is coupled to a direct current (DC) voltage source and has a bias feed microstrip electrical length less than one fifth of a fundamental wavelength of a fundamental frequency component of an input signal. A harmonic impedance transformation network can be configured to compensate for parasitic reactances of a precursor element. A tuned impedance element presents a short circuit impedance at the second harmonic impedance transformation network terminal for harmonic frequency components and presents a higher impedance for the fundamental frequency component. A fundamental impedance transformation network is configured to match a fundamental impedance transformation network input impedance for the fundamental frequency component to a load impedance of a load. Multiple instances of the harmonic impedance transformation network and the tuned impedance element can be provided.

Abstract: A matching network and method for matching a source impedance to a load impedance is provided. A bias feed microstrip structure is coupled to a direct current (DC) voltage source and has a bias feed microstrip electrical length less than one fifth of a fundamental wavelength of a fundamental frequency component of an input signal. A harmonic impedance transformation network can be configured to compensate for parasitic reactances of a precursor element. A tuned impedance element presents a short circuit impedance at the second harmonic impedance transformation network terminal for harmonic frequency components and presents a higher impedance for the fundamental frequency component. A fundamental impedance transformation network is configured to match a fundamental impedance transformation network input impedance for the fundamental frequency component to a load impedance of a load. Multiple instances of the harmonic impedance transformation network and the tuned impedance element can be provided.

Abstract: A 3-way Doherty amplifier has an amplifier input and an amplifier output. The amplifier has a main stage, a first peak stage and a second peak stage. The amplifier has an input network connecting the amplifier input to the inputs of the stages, and an output network connecting the stages to the amplifier output. The output network implements a phase shift of 90° between the output of the main stage and the amplifier output; a phase shift of 180° between the output of the first peak stage and the amplifier output; and a phase shift of 90° between the third output and the amplifier output.