Digital Null Circuit for Phase Amplitude Compensation in NDT
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional NDT/NDI systems rely on analog methods for phase and amplitude detection, leading to noise, temperature drift, and increased costs due to the need for multiple components and larger circuit boards, which hinder accurate inspection and measurement.
Innovation Solution
A digital circuit and method utilizing programmable digital components, specifically a digital null circuit and direct digital synthesizer, for phase and amplitude detection and compensation, reducing noise and temperature drift while enabling reprogrammability and compact design.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If analog methods are used for phase and amplitude detection, then the system can perform detection functions, but noise levels increase and temperature drift effects worsen
Solution Approach 1:
The patent replaces analog circuitry with digital signal processing techniques. The analog null circuit is substituted with a digital null circuit that uses software algorithms to compensate for phase and amplitude differences, eliminating the noise and temperature drift inherent in analog components while maintaining detection functionality.
Solution Approach 2:
The patent changes the fundamental parameter representation from continuous analog values to discrete digital values. By converting signals to digital format and processing them through software, the system achieves higher precision measurements while immune to the environmental factors that affect analog circuits.
2Measurement precision
If multiple analog components are used for phase and amplitude detection, then detection functionality is achieved, but system cost and complexity increase
Solution Approach 1:
The patent merges multiple analog components into a single digital processing platform. The digital null circuit integrates functions that would traditionally require separate analog components, reducing overall system complexity while maintaining or improving detection precision through software-based compensation.
Solution Approach 2:
The digital processing system serves multiple functions simultaneously - it performs phase detection, amplitude detection, nulling compensation, and temperature drift correction all within a single integrated platform, eliminating the need for separate dedicated components for each function.
3Measurement precision
If analog null circuit is used for compensation, then phase and amplitude differences can be corrected, but the compensation is limited to finite values
Solution Approach 1:
The digital null circuit provides dynamic compensation capabilities through software control. The system can adaptively adjust compensation parameters in real-time based on measured phase and amplitude differences, enabling near-infinite compensation range compared to the fixed, finite compensation of analog circuits.
Solution Approach 2:
The digital system implements feedback mechanisms where measured phase and amplitude deviations are continuously fed back to the nulling algorithm, allowing iterative correction and achieving precise compensation over a much wider range than analog circuits can provide.
Data Source
AI summary
Disclosed are a method and an NDT/NDI inspection device deploying digital circuitry to conduct detection and compensation of phase and amplitude shift in responding signals. A digital waveform generator, such as a direct digital synthesizer (DDS) is used to generate a digital sine-wave of a specific frequency and amplitude, mimicking the pulser frequency and amplitude. The sine-wave is converted to analog signal through a DAC and transmitted to the transducer. The received analog sine-wave from the transducer is converted back to a digital signal through an ADC. The transmitted and received digital signals are then compared for phase and amplitude differences. A null circuit involving another waveform generating component is employed to compensate the detected phase and amplitude differences. As a result the phase and amplitude differences are effectively eliminated before being further processed and analyzed for defects information.