Low noise amplifier providing variable gains and noise cancellation for carrier aggregation

Patent metadata

Field	Value
Publication number	US-2016173145-A1
Application number	US-201514838965-A
Country	US
Kind code	A1
Filing date	Aug 28, 2015
Priority date	Dec 16, 2014
Publication date	Jun 16, 2016
Grant date	—

Abstract

A variable-gain, low noise amplifier system includes a variable-gain, low noise amplifier, having a matching stage, coupled to an input signal with a plurality of different carrier frequencies, that provides complementary output signals containing the plurality of different carrier frequencies. The variable-gain, low noise amplifier also includes a set of carrier gain control stages, coupled to the complementary output signals, wherein each carrier gain control stage provides an independent gain for one carrier frequency of the plurality of different carrier frequencies. The variable-gain, low noise amplifier system also includes a gain controller, coupled to the variable-gain, low noise amplifier that provides gain control signals to determine the independent gain for each carrier gain control stage. A method of operating a variable-gain, low noise amplifier is also provided.

First claim

1 . A variable-gain low noise amplifier, comprising:
a matching stage coupled to an input signal having a plurality of different carrier frequencies and configured to provide complementary output signals containing the plurality of different carrier frequencies; a set of carrier gain control stages coupled to the complementary output signals, wherein each of the set of carrier gain control stages receives each of the complementary output signals from the matching stage and each is configured to provide an independent gain for one carrier frequency of the plurality of different carrier frequencies.

2 . The amplifier as recited in claim 1 wherein each of the set of carrier gain control stages includes parallel gain control cells configured to provide the independent gain.

3 . The amplifier as recited in claim 2 wherein outputs of the parallel gain control cells are coupled to a same single carrier frequency load.

4 . The amplifier as recited in claim 1 wherein each of the complementary output signals additionally contains an interfering device noise originating from the matching stage.

5 . The amplifier as recited in claim 4 wherein the interfering device noise is an in-phase device noise in each of the complementary output signals.

6 . The amplifier as recited in claim 5 wherein an amplitude of the in-phase device noise is reduced to a required level by selecting an input transconductance ratio of parallel gain control cells in each of the set of carrier gain control stages.

7 . A method of operating a variable-gain, low noise amplifier, comprising:
receiving a plurality of different carrier frequencies; processing the plurality of different carrier frequencies into complementary signals; coupling each of the complementary signals to each of a set of independent gain control paths; and providing an independent gain for one carrier frequency of the plurality of different carrier frequencies in each of the set of independent gain control paths.

8 . The method as recited in claim 7 wherein the independent gain is provided by a selection of parallel gain control cells in each of the set of independent gain control paths.

9 . The method as recited in claim 8 wherein outputs of the parallel gain control cells are coupled to a same single carrier frequency load.

10 . The method as recited in claim 7 wherein each of the complementary output signals additionally contains an interfering device noise.

11 . The method as recited in claim 10 wherein the interfering device noise is an in-phase device noise in each of the complementary signals.

12 . The method as recited in claim 11 wherein an amplitude of the in-phase device noise is reduced to a required level by selecting an input transconductance ratio of parallel gain control in each of the set of independent gain control paths.

13 . A variable-gain, low noise amplifier system, comprising:
a variable-gain, low noise amplifier, including:
a matching stage, coupled to an input signal having a plurality of different carrier frequencies, that provides complementary output signals containing the plurality of different carrier frequencies, and
a set of carrier gain control stages, each coupled to each of the complementary output signals, wherein each carrier gain control stage provides an independent gain for one carrier frequency of the plurality of different carrier frequencies; and
a gain controller, coupled to the variable-gain, low noise amplifier, that provides gain control signals to determine the independent gain for each carrier gain control stage.

14 . The system as recited in claim 13 wherein each of the set of carrier gain control stages includes parallel gain control cells that provide the independent gain.

15 . The system as recited in claim 14 wherein outputs of the parallel gain control cells are coupled to a same single carrier frequency load.

16 . The system as recited in claim 13 wherein each of the complementary output signals additionally contains an interfering device noise originating from the matching stage.

17 . The system as recited in claim 16 wherein the interfering device noise is an in-phase device noise in each of the complementary output signals.

18 . The system as recited in claim 17 wherein an amplitude of the in-phase device noise is reduced to a required level by selecting an input transconductance ratio of parallel gain control cells in each of the set of carrier gain control stages.

19 . The system as recited in claim 13 wherein the gain controller includes a gain table and a bias control circuit.

20 . The system as recited in claim 19 wherein the gain table provides gain control information for each of the set of carrier gain control stages based on its carrier frequency output amplitude and the bias control circuit provides gain control for each of the set of carrier gain control stages based on the gain control information.

Assignees

• Nvidia Corp

Inventors

• Forbes Travis
• Bellaouar Abdellatif
• Abdelhalem Sherif
• Fang Sher Jiun
• Zhang Frank

Classifications

• H04B1/0475 Primary

  with means for limiting noise, interference or distortion (H04B1/0483 takes precedence) · CPC title

• H04B1/40

  Circuits · CPC title

• H03F3/193 Primary

  with field-effect devices (H03F3/195 takes precedence) · CPC title

• H03F3/211

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

• H03F3/245

  with semiconductor devices only · CPC title