AMPLIFYING APPARATUS AND DISTORTION COMPENSATION METHOD

• US 20120154033A1
• Filed: 11/28/2011
• Published: 06/21/2012
• Est. Priority Date: 12/17/2010
• Status: Active Grant

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: Lozhkin, Alexander N.
• Granted Patent: US 8,686,791 B2
• Time in Patent Office: Days
• US Class Current: 330/124.R
• CPC Class Codes: H03F 1/3247 using feedback acting on predistortion circuits H03F1/3264 takes precedence
• CPC Class Codes: H03F 2201/3212 Using a control circuit to adjust amplitude and phase of a signal in a signal path
• CPC Class Codes: H03F 3/211 using a combination of several amplifiers H03F3/60 takes precedence

Abstract

An amplifying apparatus includes: a plurality of amplifiers; a linear combiner receiving a plurality of leakage signals resulting from cross leakage between outputs of the plurality of amplifiers and performing a linear combination of level values of the plurality of leakage signals to generate a plurality of linear combination signals; and an output calculator calculating real level values of a plurality of output amplified signals of the amplifiers from level values of the linear combination signals.

Claims

1. An amplifying apparatus comprising:

a plurality of amplifiers;

a linear combiner configured to receive a plurality of leakage signals resulting from cross leakage between outputs of the plurality of amplifiers and configure to perform a linear combination of level values of the plurality of leakage signals to generate a plurality of linear combination signals; and

an output calculator configured to calculate real level values of a plurality of output amplified signals of the amplifiers from level values of the linear combination signals.

2. The amplifying apparatus according to claim 1, further comprising a distortion compensator configured to compensate for distortion of outputs of the amplifiers, wherein the distortion compensator generates a correction signal reducing an error between the level value of an input signal input into the amplifiers and the real level value of the output amplified signals to a predetermined value and superimposes the correction signal on the input signal of the amplifiers.

3. An amplifying apparatus comprising:

a first amplifier;

a second amplifier;

a linear combiner configured to receive a first leakage signal from the first amplifier resulting from cross leakage and a second leakage signal from the second amplifier resulting from cross leakage, and configure to perform a linear combination of a level value of the first leakage signal and a level value of the second leakage signal to generate a first linear combination signal and a second combination signal; and

an output calculator configured to calculate a real level value of a first output amplified signal of the first amplifier and a real level value of a second output amplified signal of the second amplifier from a level value of the first linear combination signal and a level value of the second linear combination signal.

4. The amplifying apparatus according to claim 3, wherein:

the linear combiner generates the first linear combination signal having a level value y₊ and the second linear combination signal having a level value y₋

, the level values y₊ and y₋

being expressed by a matrix as

5. The amplifying apparatus according to claim 4, wherein:

the output calculator premultiplies both sides of the matrix equation

6. The amplifying apparatus according to claim 3, wherein the linear combiner comprises:

a first combiner combining the first leakage signal with the second leakage signal to generate the first linear combination signal;

a first phase shifter shifting the phase of the first leakage signal by +90 degrees;

a second phase shifter shifting the phase of the second leakage signal by −

90 degrees; and

a second combiner combining an output signal from the first phase shifter with an output signal from the second phase shifter to generate the second linear combination signal.

7. The amplifying apparatus according to claim 3, further comprising a first distortion compensator configured to compensate for distortion of an output of the first amplifier and a second distortion compensator compensating for distortion of an output of the second amplifier;

wherein;

the first distortion compensator generates a first correction signal reducing an error between a level value of an input signal input into the first amplifier and the real level value of the first output amplified signal to a predetermined value and superimposes the first correction signal on the input signal of the first amplifier; and

the second distortion compensator generates a second correction signal reducing an error between a level value of an input signal input into the second amplifier and the real level value of the second output amplified signal to a predetermined value and superimposes the second correction signal on the input signal of the second amplifier.

8. A distortion compensation method, comprising:

performing a linear combination of level values of a plurality of leakage signals resulting from cross leakage between outputs of a plurality of amplifiers to generate a plurality of linear combination signals;

calculating real level values of a plurality of output amplified signals of the amplifiers from level values of the linear combination signals;

generating a correction signal reducing an error between the level value of an input signal input into the amplifiers and the real level value of the output amplified signals to a predetermined value; and

superimposing the correction signal on the input signals of the amplifiers to compensate for distortion of the outputs of the amplifiers.