Radar Fill Level Sensor Doppler Noise Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current fill level measurement methods using radar sensors face challenges in accurately identifying the fill substance surface due to interference from the fill substance stream entering the radiation field, leading to false fill level information, especially during filling or stirring processes.
Innovation Solution
The method involves recording and evaluating both the echo curve and Doppler frequency spectrum to dynamically adapt averaging factors and correct fill level identification, using Doppler frequency information to distinguish between the fill substance surface and noise echoes, and accounting for flow velocities and directions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If radar sensor is used for fill level measurement, then measurement capability is provided, but false fill level information occurs when fill substance stream enters radiation field
Solution Approach 1:
The patent introduces Doppler frequency spectrum analysis as an intermediary evaluation method to distinguish between true fill level echoes and noise echoes from fill substance streams. The Doppler spectrum serves as a mediator that provides additional information about the motion state of reflected signals, enabling the electronic evaluation unit to correctly identify fill level structures even when fill substance streams are present in the radiation field.
Solution Approach 2:
The patent transitions from single-dimensional echo curve analysis to two-dimensional evaluation by incorporating Doppler frequency spectrum analysis. This additional dimensional information about velocity and motion state allows the system to differentiate between stationary fill level surfaces and moving fill substance streams, resolving the ambiguity that causes false measurements.
2Productivity
If electronic evaluation unit identifies structures in echo curve, then fill level is calculated, but incorrect structure identification leads to false fill level information
Solution Approach 1:
The patent implements feedback by using Doppler frequency spectrum results to guide and correct the identification of structures in the echo curve. The electronic evaluation unit continuously monitors Doppler characteristics and uses this feedback information to adjust its interpretation of echo curve structures, ensuring accurate fill level determination even during dynamic filling operations.
Solution Approach 2:
The patent changes the evaluation parameters from solely spatial/temporal echo curve analysis to include Doppler frequency domain analysis. By introducing velocity-related parameters from Doppler spectrum, the system gains the ability to distinguish between different types of reflected signals based on their motion characteristics, significantly improving structure identification accuracy.
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 approach significantly improves the accuracy of fill level measurement by differentiating between the fill substance surface and noise echoes, providing reliable fill level data even during filling or stirring, and allowing for real-time correction of distorted measurements.
Implementation Method 1
The basic principle of such a measurement is the radiation of a signal into the container and, for example, recording the travel time distribution of the reflected radar echo
Implementation Method 2
recording the travel time distribution of the reflected radar echo
Implementation Method 3
The determination of the flow velocity and the distance to a flowing medium with the aid of the Doppler method
Data Source
AI summary
Provided are a method for measuring the fill level of a fill substance with at least one radar sensor and with at least one electronic evaluation unit comprising the steps recording of an echo curve, recording of a Doppler frequency spectrum, evaluation of the Doppler frequency spectrum by the electronic evaluation unit and evaluation of the echo curve by the electronic evaluation unit taking into consideration the results of the evaluation of the Doppler frequency spectrum by the electronic evaluation unit, as well as a fill level measuring device with at least one radar sensor and an electronic control and evaluation unit, that is set up for the implementation of such a method.