Power Amplifier Predistortion via Block-Diagonal ADC Sampling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing digital predistortion (DPD) systems face challenges in meeting the increasing performance requirements of wireless communication applications due to the nonlinearity of power amplifiers, which causes spectral growth and distortions, leading to increased bit error rates and complex data processing demands.

Innovation Solution

A model identification system that uses an analog-to-digital converter (ADC) with a block diagonal sampling matrix to reduce the data rate and computational complexity by generating a digital signal with a lower sampling rate, allowing for efficient predistortion of power amplifiers in communication systems.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If a high sampling rate is used in the ADC to capture power amplifier output signals accurately, then measurement precision is improved, but data rate and computational complexity increase

Engineering Contradiction:
Improvesignal capture accuracyVSAvoidcomputational complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The sampling matrix is segmented into a block diagonal structure with multiple diagonal blocks, where each block corresponds to a subset of signal components. This segmentation allows the system to process different signal components separately at reduced sampling rates, thereby reducing overall computational complexity while maintaining measurement precision for critical signal components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system changes the sampling rate parameter dynamically by using a block diagonal sampling matrix with different sampling rates for different signal components. This allows high sampling rates to be applied only where necessary for measurement precision, while lower sampling rates are used for other components, thus reducing overall data rate and computational complexity.

Inventive Principle:
Principle #35Parameter changes

2Measurement precision

If a high sampling rate is used in the ADC to capture power amplifier output signals accurately, then measurement precision is improved, but data transmission rate increases

Engineering Contradiction:
Improvesignal capture accuracyVSAvoiddata rate
Core Design Contradiction:
Measurement precisionVSProductivity

Solution Approach 1:

The sampling matrix is segmented into a block diagonal structure with multiple diagonal blocks, where each block corresponds to a subset of signal components. This segmentation allows the system to process different signal components separately at reduced sampling rates, thereby reducing overall computational complexity while maintaining measurement precision for critical signal components.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The system changes the sampling rate parameter dynamically by using a block diagonal sampling matrix with different sampling rates for different signal components. This allows high sampling rates to be applied only where necessary for measurement precision, while lower sampling rates are used for other components, thus reducing overall data rate and computational complexity.

Inventive Principle:
Principle #35Parameter changes

3Reliability

If complex predistortion models are used to compensate for power amplifier nonlinearity, then performance is improved, but device complexity increases

Engineering Contradiction:
ImproveperformanceVSAvoidsystem complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The predistortion model is segmented into multiple components corresponding to different diagonal blocks of the sampling matrix. Each component processes a specific subset of signal characteristics, allowing the complex predistortion task to be divided into manageable parts that can be implemented with reduced overall system complexity while maintaining comprehensive performance.

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3580847B1Method and apparatus for model identification and predistortion
Publication Date: 2023.06.07 XILINX INC
  • EP3580847B1 patent drawingFigure 1
  • EP3580847B1 patent drawingFigure 2
  • EP3580847B1 patent drawingFigure 3

AI summary

A model identification system [FIG. 8A, 800] includes an analog to digital converter (ADC) [FIG. 8A, 210]. The ADC includes a conversion circuit [FIG. 8A, 212] configured to receive a first analog signal [FIG. 8A, 208] and generate a first digital signal [FIG. 8A, 214] including samples having a first rate by sampling the first analog signal at the first rate. The ADC further includes a first digital signal processing (DSP) circuit [FIG. 8A, 802] configured to generate a second digital signal [FIG. 8A, 804] including samples having a second rate less than the first rate based on the first digital signal and a first sampling matrix [FIG. 8B, 854A; FIG. 9, Dbikones]. The first sampling matrix is a block diagonal matrix including a plurality of diagonal blocks, each diagonal block is a row vector including a plurality of elements.