Impedance matching circuit with tunable notch filters for power amplifier

摘要

An impedance matching circuit with at least one tunable notch filter for a power amplifier is disclosed. The power amplifier amplifies an input radio frequency (RF) signal and provides an amplified RF signal. The impedance matching circuit performs output impedance matching for the power amplifier and includes at least one tunable notch filter. Each tunable notch filter has a notch that can be varied in frequency to provide better attenuation of an undesired signal. The at least one tunable notch filter attenuates at least one undesired signal in the amplified RF signal. The at least one tunable notch filter may include (i) a first tunable notch filter to attenuate a first undesired signal at a second harmonic of the amplified RF signal and/or (ii) a second tunable notch filter to attenuate a second undesired signal at a third harmonic of the amplified RF signal.

主权项

1. An apparatus comprising:
a power amplifier configured to amplify an input radio frequency (RF) signal and provide an amplified RF signal; and an impedance matching circuit coupled to the power amplifier and configured to match an output impedance of the power amplifier, the impedance matching circuit comprising at least one tunable notch filter dynamically adjusted during operation in response to a change in operating band of the input RF signal to attenuate at least one undesired signal in the amplified RF signal.