Gain Control Method for a Broadband Inductorless Low Noise Amplifier

• US 20140162732A1
• Filed: 12/07/2012
• Published: 06/12/2014
• Est. Priority Date: 12/07/2012
• Status: Active Grant

• Current Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Futurewei Technologies Incorporated (Huawei Investment & Holding Co., Ltd.)
• Inventors: Yin, Ping, Irvine, Robert Grant, Liao, Chengfang, Zhang, Zhihang
• Granted Patent: US 9,893,693 B2
• Time in Patent Office: Days
• US Class Current: 455/571
• CPC Class Codes: H03F 1/22 by use of cascode coupling, i.e. earthed cathode or emitter stage followed by earthed grid or base stage respectively
• CPC Class Codes: H03F 3/193 with field-effect devices H03F3/195 takes precedence
• CPC Class Codes: H03G 3/00 Gain control in amplifiers or frequency changers
• CPC Class Codes: H03G 3/3036 in high-frequency amplifiers or in frequency-changers H03G3/3052, H03G3/32, H03G3/34 take precedence
• CPC Class Codes: H04B 1/18 Input circuits, e.g. for coupling to an antenna or a transmission line coupling networks between antennas or lines and receivers independent of the nature of the receiver H03H
• CPC Class Codes: H04B 1/3827 Portable transceivers

Abstract

A mobile device comprising an antenna, a receiver coupled to the antenna, and a transmitter coupled to the antenna, wherein the receiver, the transmitter, or both comprise a low noise amplifier comprising an adjustable gain and a variable impedance controller, and wherein the low noise amplifier is configured to sink current and to adjust a shunt resistance substantially simultaneously. Included is a method comprising receiving an electrical signal, substantially simultaneously adjusting an input impedance and a gain factor, amplifying the electrical signal, thereby producing an amplified signal, and outputting the amplified signal.

Claims

1. A mobile device comprising:

an antenna;

a receiver coupled to the antenna; and

a transmitter coupled to the antenna,

wherein the receiver, the transmitter, or both comprise a low noise amplifier comprising an adjustable gain and a variable impedance controller, and

wherein the low noise amplifier is configured to sink current and to adjust a shunt resistance substantially simultaneously.

2. The mobile device of claim 1, wherein the variable impedance controller comprises one or more transistors and one or more resistors in parallel with the one or more transistors.

3. The mobile device of claim 2, wherein the variable impedance controller further comprises two or more of the transistors in parallel with the resistors in series with each other.

4. The mobile device of claim 2, wherein the variable impedance controller further comprises two or more of the transistors in parallel with the resistors in parallel with each other.

5. The mobile device of claim 4, wherein the low noise amplifier comprises two or more current flow paths in parallel, and wherein current flow paths in parallel comprises a connection to a ground.

6. The mobile device of claim 1, wherein substantially simultaneously is within about one second of each other.

7. The mobile device of claim 1, wherein substantially simultaneously is at least partially concurrent.

8. A method comprising:

receiving an electrical signal;

substantially simultaneously adjusting an input impedance and a gain factor;

amplifying the electrical signal, thereby producing an amplified signal; and

outputting the amplified signal.

9. The method of claim 8, wherein the input impedance is adjusted by adjusting a shunt resistance.

10. The method of claim 9, wherein the shunt resistance is adjusted by configuring a variable impedance controller.

11. The method of claim 10, wherein an input impedance is maintained substantially constant.

12. The method of claim 11, wherein the gain factor is adjusted sinking at least a portion of the current to a ground.

13. The method of claim 11, wherein at least a portion of a current is diverted away from a load.

14. The mobile device of claim 8, wherein substantially simultaneously is within about one second of each other.

15. The mobile device of claim 8, wherein substantially simultaneously is at least partially concurrent.

16. An amplifier comprising:

an input connection;

an output connection;

a variable impedance controller coupled to the input connection and the output connection, wherein the variable impedance controller is configured to have an adjustable impedance;

a current source;

a first transistor comprising a first interface coupled to the current source, a second interface coupled to the output connection, and a third interface coupled to the input connection and is configurable between a first state and a second state, wherein when the first transistor is in the first state, the first transistor prevents a route of electrical current via the first interface and the second interface of the first transistor, and wherein when the first transistor is in the second state, the first transistor allows a route of electrical current via the first interface and the second interface of the first transistor;

a ground; and

a second transistor comprising a first interface coupled to the current source, a second interface coupled to the ground, and a control interface and is configurable between a first state and a second state, wherein when the second transistor is in the first state, the second transistor prevents a route of electrical current via the first interface and the second interface of the second transistor, and wherein when the second transistor is in the second state, the second transistor allows a route of electrical current via the first interface and the second interface of the second transistor.

17. The amplifier of claim 16, wherein the variable impedance controller comprises one or more transistors and one or more resistors in parallel with the one or more transistors.

18. The amplifier of claim 16, wherein the current source comprises a transistor coupled to a voltage source, the first transistor, and the second transistor.

19. The amplifier of claim 16, wherein the current source comprises a transistor coupled to the ground, the first transistor, and the second transistor.

20. The amplifier of claim 16, further comprising one or more transistors in parallel with the second transistor.