Power amplifier and power amplification method

Patent metadata

Field	Value
Publication number	US-9531327-B2
Application number	US-201314434137-A
Country	US
Kind code	B2
Filing date	Oct 29, 2013
Priority date	Oct 31, 2012
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

When frequency allocation for a plurality of frequencies is in an intra-band CA relationship, a first amplifier is operated in class B, a second amplifier is operated in class C, and a power modulator is caused to supply a constant voltage to the first and second amplifiers so as to operate as a Doherty-type power amplifier. In addition, when the frequency allocation for the plurality of frequencies is in an inter-band non-contiguous CA relationship, the first and second amplifiers are operated in class B, and the power modulator is caused to supply a voltage proportional to the amplitude component of an input signal to the first and second amplifiers so as to operate as a power amplifier based on an ET system.

First claim

The invention claimed is:

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.

2. 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 a square root of an output power sum of the first and second amplifiers is supplied as the power supply voltage from the power modulator to the first and second amplifiers.

3. A power amplifier comprising:
a power divider for distributing an input signal including a plurality of carrier frequencies to three amplifiers;
a first amplifier for amplifying and outputting a first signal 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 transmission line having a length equivalent to a ½ wavelength of the carrier frequency included in the input signal;
a second amplifier for receiving a second signal divided by the power divider via the first transmission line and amplifying and outputting the second signal;
a third amplifier for receiving a third signal divided by the power divider via the second transmission line and amplifying and outputting the third signal;
a power modulator for supplying a power supply voltage to the first, second and third 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 third matching circuit connected to an output end of the third amplifier and configured to match output impedance of the third amplifier with the impedance of the load;
a third transmission line having 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;
a fourth transmission line having a length equivalent to a ¼ wavelength of the carrier frequency, one end connected to the output end of the second matching circuit, and the other end connected to an output end of the third matching circuit, and configured to supply a synthesized signal of output signals of the first, second and third amplifiers to the load from the other end;
a control unit configured to set operation classes of the first, second and third amplifiers and supply a control signal for controlling the power supply voltage supplied to the first, second and third 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 and third amplifiers are operated in class C, and
a predetermined constant voltage is supplied as the power supply voltage from the power modulator to the first, second, and third amplifiers; and
when the frequency allocation of the plurality of carrier frequencies is in an inter-band non-contiguous carrier aggregation relationship,
the first, second, and third 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, second, and third amplifiers.

4. A power amplifier comprising:
a power divider for distributing an input signal including a plurality of carrier frequencies to three amplifiers;
a first amplifier for amplifying and outputting a first signal divided by th

Assignees

• Nec Corp

Inventors

• Kunihiro Kazuaki

Classifications

• H03F3/24

  of transmitter output stages · CPC title

• H03F2200/102

  A non-specified detector of a signal envelope being used in an amplifying circuit · CPC title

• H03F3/211

  using a combination of several amplifiers (H03F3/60 takes precedence) · CPC title

• H03F1/0288 Primary

  using a main and one or several auxiliary peaking amplifiers whereby the load is connected to the main amplifier using an impedance inverter, e.g. Doherty amplifiers · CPC title

• H03F3/19

  with semiconductor devices only · CPC title