Radio frequency power amplifier

Patent metadata

Field	Value
Publication number	US-10116277-B2
Application number	US-201715427937-A
Country	US
Kind code	B2
Filing date	Feb 8, 2017
Priority date	Jun 17, 2016
Publication date	Oct 30, 2018
Grant date	Oct 30, 2018

Abstract

A radio frequency (RF) power amplifier includes an amplifying stage that includes an amplifying module, an input module and a feedback module. The amplifying module receives an RF to-be-amplified signal, and performs power amplification on the RF to-be-amplified signal to generate an RF output signal. The input module receives an RF input signal. The feedback module receives the RF output signal, cooperates with the input module to provide the RF to-be-amplified signal based on the RF input and output signals, and cooperates with the amplifying module to forma positive feedback loop that provides a loop gain which is less than one.

First claim

What is claimed is:

1. A radio frequency (RF) power amplifier comprising:
a number (N) of amplifying stages, each receiving a respective RF input signal and outputting a respective RF output signal, where N≥1;
when N≥2, said amplifying stages being cascaded, and the respective RF output signal outputted by an n th one of said amplifying stages serving as the respective RF input signal received by an (n+1) th one of said amplifying stages, where 1≤n≤(N−1);
each of first to M th ones of said amplifying stages including
a first amplifying module receiving a first RF to-be-amplified signal, and performing power amplification on the first RF to-be-amplified signal to generate the respective RF output signal and an RF inverted signal that is anti-phase with the first RF to-be-amplified signal,
an input module coupled to said first amplifying module, and receiving the respective RF input signal, and
a feedback module coupled to said first amplifying module and said input module, and receiving the respective RF output signal from said first amplifying module, said feedback module cooperating with said input module to provide, based on the respective RF input signal and the respective RF output signal, the first RF to-be-amplified signal for said first amplifying module, said feedback module cooperating with said first amplifying module to form a positive feedback loop that provides a loop gain which is less than one, a portion of the first RF to-be-amplified signal that is contributed by the respective RF output signal being anti-phase with the RF inverted signal,
where 1≤M≤N;

for each of said first to M th ones of said amplifying stages, said first amplifying module including:
a transistor having a first terminal that provides the RF inverted signal, a second terminal that is grounded, and a control terminal that is coupled to said input module and said feedback module for receiving the first RF to-be-amplified signal therefrom;
a first inductor having a first terminal that is coupled to said feedback module and that provides the respective RF output signal, and a second terminal that is coupled to said first terminal of said transistor; and
a second inductor having a first terminal that is used to receive a supply voltage, and a second terminal that is coupled to said first terminal of said first inductor.

2. The RF power amplifier of claim 1 , wherein for each of said first to M th ones of said amplifying stages, said feedback module includes:
a capacitor having a first terminal that is coupled to said control terminal of said transistor, and a second terminal; and
a third inductor coupled between said second terminal of said capacitor and said first terminal of said first inductor.

3. The RF power amplifier of claim 2 , wherein for each of said first to M th ones of said amplifying stages, each of said first to third inductors is a transmission line inductor with a predetermined electrical length, and a sum of the predetermined electrical lengths of said first and third inductors equals half a wavelength of the respective RF input signal.

4. A radio frequency (RF) power amplifier comprising:
a number (N) of amplifying stages, each receiving a respective RF input signal and outputting a respective RF output signal, where N≥1;
when N≥2, said amplifying stages being cascaded, and the respective RF output signal outputted by an n th one of said amplifying stages serving as the respective RF input signal received by an (n+1) th one of said amplifying stages, where 1≤n≤(N−1);
each of first to M th ones of said amplifying stages including
a first amplifying module receiving a first RF to-be-amplified signal, and performing power amplification on the first RF to-be-amplified signal to generate the respective RF output signal,
an input module coupled to said first amplifying module, and receiving the respective RF input signal, and
a feedback module coupled to said first amplifying module and said input module, and receiving the respective RF output signal from said first amplifying module, said feedback module cooperating with said input module to provide, based on the respective RF input signal and the respective RF output signal, the first RF to-be-amplified signal for said first amplifying module, said feedback module cooperating with said first amplifying module to form a positive feedback loop that provides a loop gain which is less than one,
where 1≤M≤N;

for each of said first to M th ones of said amplifying stages, said input module including:
a capacitor having a first terminal that is used to receive the respective RF input signal, and a second terminal;
a first inductor having a first terminal that is coupled to said second terminal of said capacitor, and a second terminal that is coupled to said first amplifying module and said feedback module and that provides the first RF to-be-amplified signal; and
a second inductor having a first terminal that is coupled to said second terminal of said capacitor, and a second terminal that is used to receive a supply voltage.

5. The RF power amplifier of claim 1 , wherein for each of said first to M th ones of said amplifying stages, said input module determines an input impedance seen into said amplifying stage.

6. The RF power amplifier of claim 5 , wherein for said first one of said amplifying stages, said input module is used to be coupled to a pre-stage circuit for receiving the respective RF input signal therefrom, and is configured such that the input impedance seen into said amplifying stage matches an output impedance seen into the pre-stage circuit.

7. The RF power amplifier of claim 5 , wherein N≥2, 2≤M≤N, and for an m th one of said amplifying stages, said input module is configured such that the input impedance seen into said amplifying stage matches an output impedance seen into an (m−1) th one of said amplifying stages, where 2≤m≤M.

8. A radio frequency (RF) power amplifier comprising:
a number (N) of amplifying stages, each receiving a respective RF input signal and outputting a respective RF output signal, where N≥2;
said amplifying stages being cascaded, and the respective RF output signal outputted by an n th one of said amplifying stages serving as the respective RF input signal received by an (n+1) th one of said amplifying stages, where 1≤n≤(N−1);
each of first to M th ones of said amplifying stages including
a first amplifying module receiving a first RF to-be-amplified signal, and performing power amplification on the first RF to-be-amplified signal to generate the respective RF output signal,
an input module coupled to said first amplifying module, and receiving the respective RF input signal, and
a feedback module coupled to said first amplifying module and said input module, and receiving the respective RF output signal from said first amplifying module, said feedback module cooperating with said input module to provide, based on the respective RF input signal and the respective RF output signal, the first RF to-be-amplified signal for said first amplifying module, said feedback module cooperating with said first amplifying module to form a positive feedback loop that provides a loop gain which is less than one,
where 1≤M≤N−1;

an (M+1) th one of said amplifying stages including:
a first impedance matching module receiving the respective RF input signal, providing a second RF to-be-amplified signal based on the respective RF input signal, and determining an input impedance seen into said amplifying stage;
a second amplifying module coupled to said first impedance matching module for receiving the second RF to-be-amplified signal therefrom, said second amplifying module dividing the second RF to-be-amplified signal into two first RF divided s

Assignees

• Univ Nat Chi Nan

Inventors

• Lin Yo-Sheng
• Nguyen Van-Kien

Classifications

• H03F2200/222

  A circuit being added at the input of an amplifier to adapt the input impedance of the amplifier · CPC title

• H03F3/607 Primary

  using FET's · CPC title

• H03F2200/451

  the amplifier being a radio frequency amplifier · CPC title

• H03F3/21

  with semiconductor devices only {(H03F3/245 takes precedence)} · CPC title

• H03F1/56

  Modifications of input or output impedances, not otherwise provided for · CPC title