Doherty Amplifier Splitter Calibration for Phase and Attenuation States

Solution Overview

Problem

Calibrating a Doherty amplifier's power splitter with adjustable attenuation and phase states is impractical due to the large number of possible combinations, making it time-consuming and inefficient to find optimal settings for desired RF performance.

Innovation Solution

A method and system for efficiently calibrating the power splitter by reducing the number of combinations tested, using a controller to set and sweep adjustable attenuators and phase shifters to identify optimal states, such as State 1 for peak power, State 2 for maximum efficiency, and State 3 for optimal configuration, while ensuring linearization and minimizing iterations.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If all possible combinations of attenuation and phase states are inspected to identify optimum calibration, then manufacturing precision is improved, but loss of time increases

Engineering Contradiction:

Improvecalibration precisionVSAvoidcalibration time

Core Design Contradiction:

Manufacturing precisionVSLoss of time

Solution Approach 1:

The patent segments the calibration process into two distinct phases: a comprehensive initial calibration that inspects all possible combinations of attenuation and phase states to establish accurate lookup tables, and subsequent operational phases that use pre-computed calibration data. This segmentation allows the time-consuming precise calibration to be performed once during manufacturing or initialization, while rapid calibration is achieved during normal operation.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent performs preliminary calibration by pre-computing and storing lookup tables containing optimal attenuation and phase states for various operating conditions during manufacturing or system initialization. This preliminary action eliminates the need to inspect all possible combinations during subsequent operational calibrations, significantly reducing calibration time while maintaining precision through the use of pre-stored optimal values.

Inventive Principle:

Principle #10Preliminary action

2Productivity

If the number of attenuation and phase state combinations is reduced for calibration, then productivity is improved, but manufacturing precision deteriorates

Engineering Contradiction:

Improvecalibration efficiencyVSAvoidcalibration accuracy

Core Design Contradiction:

ProductivityVSManufacturing precision

Solution Approach 1:

The patent performs preliminary calibration by pre-computing and storing lookup tables containing optimal attenuation and phase states for various operating conditions during manufacturing or system initialization. This preliminary action eliminates the need to inspect all possible combinations during subsequent operational calibrations, significantly reducing calibration time while maintaining precision through the use of pre-stored optimal values.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The patent creates simplified copies of the full calibration data in the form of lookup tables that store pre-computed optimal attenuation and phase states for different operating conditions. These lookup table copies allow rapid calibration during operation without requiring access to or inspection of all possible state combinations, thereby maintaining calibration accuracy while improving productivity.

Inventive Principle:

Principle #26Copying

3Reliability

If comprehensive calibration of all states is performed, then reliability is improved, but device complexity increases

Engineering Contradiction:

Improveamplifier performanceVSAvoidcalibration system complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The patent creates simplified copies of the full calibration data in the form of lookup tables that store pre-computed optimal attenuation and phase states for different operating conditions. These lookup table copies allow rapid calibration during operation without requiring access to or inspection of all possible state combinations, thereby maintaining calibration accuracy while improving productivity.

Inventive Principle:

Principle #26Copying

Solution Approach 2:

The patent segments the calibration process into a comprehensive initial calibration phase that ensures reliability through complete state inspection, and subsequent operational phases that use pre-computed data. This segmentation isolates the complexity of comprehensive calibration to a single initial process while simplifying ongoing operations.

Inventive Principle:

Principle #1Segmentation

Data Source

PatentUS8957734B2Amplifier calibration

Publication Date: 2015.02.17 NXP USA INC

AI summary

A system and method of calibrating an amplifier are presented. The amplifier has a first amplification path and a second amplification path. A first state of the amplifier is identified defining a first phase shift of the first path and a second phase shift of the second path resulting in a maximum efficiency of the amplifier when an attenuation of the first path and an attenuation of the second path are set to first attenuation values. The attenuation of the first path and the attenuation of the second path is set to achieve a maximum efficiency of the amplifier when the phase shift of the first path and the phase shift of the second path are set according to the first state.