FIR-Based Phase and Amplitude Detection for Harmonic-Rich Signals

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing electronic devices face challenges in accurately detecting phase and amplitude of signals with high harmonic content, often requiring complex circuitry and long computation times, and struggle to correct for phase errors in reference signals used for phase detection.

Innovation Solution

The implementation of a phase and amplitude detection circuit using a pair of finite impulse response (FIR) filters and a controller that generates sinusoidal signals from square wave references, allowing for accurate phase detection by mixing these signals with input signals and filtering out harmonics, thereby correcting for phase errors and determining signal characteristics efficiently.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If existing phase detection circuits are used, then phase detection can be performed, but the circuits introduce harmonic distortions and require complex circuitry

Engineering Contradiction:
Improvephase detection accuracyVSAvoidcircuit complexity
Core Design Contradiction:
Measurement precisionVSDevice complexity

Solution Approach 1:

The detection system is divided into multiple independent FIR filters, each responsible for detecting specific harmonic components. This segmentation allows the complex detection task to be distributed across simpler filter units, reducing overall circuit complexity while maintaining detection accuracy

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

FIR filters are introduced as intermediary elements between the input signal and the detection process. These filters act as mediators that selectively pass specific frequency components while blocking others, enabling accurate phase detection without requiring complex direct detection circuits

Inventive Principle:
Principle #24Intermediary (Mediator)

2Measurement precision

If existing phase detection methods are used, then phase information can be obtained, but relatively long computation times are required

Engineering Contradiction:
Improvephase detection capabilityVSAvoidcomputation time
Core Design Contradiction:
Measurement precisionVSLoss of time

Solution Approach 1:

The FIR filters perform preliminary filtering of the input signal to extract specific harmonic components before the actual phase detection computation. This preliminary action simplifies subsequent calculations by reducing the complexity of the signal that needs to be processed, thereby decreasing overall computation time

Inventive Principle:
Principle #10Preliminary action

3Productivity

If reference signals with harmonics are used for phase detection, then detection can proceed, but phase errors are introduced

Engineering Contradiction:
Improvedetection operationVSAvoidphase detection accuracy
Core Design Contradiction:
ProductivityVSMeasurement precision

Solution Approach 1:

The FIR filters extract only the fundamental frequency component from the reference signal by filtering out harmonic components. This extraction process eliminates the source of phase errors while preserving the essential signal for accurate phase detection, maintaining detection operation without compromising precision

Inventive Principle:
Principle #2Taking out (Extraction)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

This solution enables precise detection of phase and amplitude of input signals with high harmonic content, corrects for phase errors in reference signals, and accommodates a wide range of input signal amplitudes, improving the accuracy and efficiency of impedance matching in wireless power transfer systems.

Implementation Method 1

The first FIR filter receives an input signal and a first reference signal. The first FIR filter filters the first reference signal to generate a first sinusoidal signal

Methodology Applied
Scientific EffectFinite Impulse Response (FIR) filtering: Filter (electronic)

Implementation Method 2

The first FIR filter filters the first reference signal to generate a first sinusoidal signal and mixes the first sinusoidal signal and the input signal to generate a first mixed signal

Methodology Applied
Scientific EffectSignal mixing: Homodyne Detection

Data Source

PatentEP3362804B1Phase and amplitude detection in wireless energy transfer systems
Publication Date: 2024.01.17 WITRICITY CORP
  • EP3362804B1 patent drawingFigure 1
  • EP3362804B1 patent drawingFigure 2A~2B
  • EP3362804B1 patent drawingFigure 3

AI summary

Methods, systems, and apparatus, including computer programs encoded on a computer storage medium, for detecting characteristics of an input signal. One aspect includes a first finite input response (FIR) filter, a second FIR filter, and a controller coupled with the first and second FIR filters. The first FIR filter receives an input signal and a first reference signal. The first FIR filter filters the first reference signal to generate a first sinusoidal signal and mixes the first sinusoidal signal and the input signal to generate a first mixed signal. The second FIR filter receives the input signal and a second reference signal. The second FIR filter filters the second reference signal to generate a second sinusoidal signal and mixes the second sinusoidal signal and the input signal to generate a second mixed signal. The controller determines characteristics of the input signal based on the first and second mixed signals.