Doherty amplifier with defected ground structures

Abstract

The invention discloses a Doherty amplifier with defected ground structures. The Doherty amplifier comprises a signal separator, a main amplification circuit, at least one auxiliary amplification circuit and a signal combiner; the signal separator separates input signals and then sends the separated input signals to the main amplification circuit and the auxiliary amplification circuits; the mainamplification circuit and the auxiliary amplification circuits amplify the signals separated by the signal separator respectively and then input the amplified signals to the signal combiner; the signal combiner combines the signals amplified by the main amplification circuit and the auxiliary amplification circuits and then outputs the combined signals; each auxiliary amplification circuit comprises a peak value amplifier, and the lower portion of a transmission line of an output end of each peak value amplifier is provided with a first defected ground structure. According to the Doherty amplifier with the defected ground structures, the lower portions of the transmission lines of the output ends of the peak value amplifiers are provided with the first defected ground structure, so that the harmonic component of the output signals of the auxiliary amplification circuits is inhibited, and the output power, power added efficiency and linearity of the Doherty amplifier are improved; meanwhile, through the arrangement of the first defected ground structures, the circuit size can be reduced, and the manufacturing cost is lowered.

Description

technical field [0001] The invention relates to the field of radio frequency power amplifiers, in particular to a Doherty amplifier with a ground defect structure. Background technique [0002] The rapid development of mobile communication technology, especially with the popularization of third-generation and fourth-generation mobile communication circuits and the emergence of fifth-generation mobile communication circuits, the requirements for power, bandwidth, data rate and linearity of wireless communication systems are getting higher and higher. come higher. In the field of mobile communications, traditional methods use Class AB power amplifiers to obtain better linearity while ensuring output power and efficiency. In order to obtain a higher data transmission rate within a limited bandwidth, the peak-to-average ratio of the signal is required to be relatively high, that is, the power amplifier needs to work in the power back-off state. However, when the Class AB power ...

AI Technical Summary

Problems solved by technology

Therefore, the auxiliary amplifier works under the condition of strong nonlinear bias, which will increase the harmonic component of the output signal and generate more nonlinear component signals, which is not conducive to the high linearity of the system, and the harmonic impedance will affect the Doherty The increase in output power and power-added efficiency of the amplifier adversely affects the

Images