Amplifying device
AssigneeSumitomo Electric Industries, Ltd.
InventorKoshi Hamano
Life of this patent
Estimating the term…
Abstract
An amplifying device includes a radio frequency (RF) signal input terminal to which an RF signal is input, a buffer circuit, a linearizer including a transistor, a power amplifier, and a control circuit. The control circuit outputs a first gate voltage when a level of the RF signal input is a first level, the first gate voltage causing the transistor to perform a class B operation. The control circuit outputs a second gate voltage when the level of the RF signal is a second level higher than the first level, the second gate voltage causing the transistor to perform a class AB operation. Output impedance of the buffer circuit that is seen from an input side of the linearizer is set such that a reflection loss of the RF signal input from the buffer circuit to the linearizer is a predetermined level or less.
Claims11
An amplifying device comprising:
- a radio frequency (RF) signal input terminal to which an RF signal is input;
- a buffer circuit having an input terminal connected to the RF signal input terminal, the RF signal being input to the buffer circuit through the input terminal;
- a linearizer connected to an output side of the buffer circuit;
- a power amplifier connected to an output side of the linearizer;
- and
- a control circuit,
- wherein the linearizer includes a transistor having a control terminal,
- wherein the control circuit outputs a first gate voltage to the control terminal when a level of the RF signal input to the RF signal input terminal is a first level, the first gate voltage causing the transistor to perform a class B operation,
- wherein the control circuit outputs a second gate voltage to the control terminal when the level of the RF signal input to the RF signal input terminal is a second level that is higher than the first level, the second gate voltage causing the transistor to perform a class AB operation, and
- wherein an output impedance of the buffer circuit that is seen from an input side of the linearizer is set such that a reflection loss of the RF signal input from the buffer circuit to the linearizer is less than or equal to a predetermined level.
Dependencies are inferred from the claim text.