Patent ID: 9531327
Filing Date: 2016-12-27
CPC Classification: H03F

Claim Text:
1. A power amplifier comprising: a power divider for distributing an input signal including a plurality of carrier frequencies to two amplifiers; a first amplifier for amplifying and outputting one of the signals divided by the power divider; a first transmission line having a length equivalent to a ¼ wavelength of the carrier frequency included in the input signal; a second amplifier for receiving the other signal divided by the power divider via the first transmission line and amplifying and outputting the other signal; a power modulator for supplying a power supply voltage to the first and second amplifiers; a first matching circuit connected to an output end of the first amplifier and configured to match output impedance of the first amplifier with impedance of a load; a second matching circuit connected to an output end of the second amplifier and configured to match output impedance of the second amplifier with the impedance of the load; a second transmission line having a length equivalent to a ¼ wavelength of the carrier frequency, one end connected to an output end of the first matching circuit, and the other end connected to an output end of the second matching circuit, and configured to supply a synthesized signal of output signals of the first and second amplifiers to the load from the other end; a control unit configured to set operation classes of the first and second amplifiers and supply a control signal for controlling the power supply voltage supplied to the first and second amplifiers to the power modulator; and when frequency allocation of the plurality of carrier frequencies is in an intra-band carrier aggregation relationship, the first amplifier is operated in class B while the second amplifier is operated in class C, and a predetermined constant voltage is supplied as the power supply voltage from the power modulator to the first and second amplifiers; and when the frequency allocation of the plurality of carrier frequencies is in an inter-band non-contiguous carrier aggregation relationship, the first and second amplifiers are operated in class B, and a voltage proportional to an amplitude component of the input signal is supplied as the power supply voltage from the power modulator to the first and second amplifiers.