Ultrasonic Sensor Signal Correlation for Bumper Noise Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing ultrasonic environment monitoring systems in motor vehicles face challenges in maintaining effective signal evaluation without increasing costs or technical complexity, particularly when sensors are installed in a concealed manner, as they struggle with noise suppression and interference, especially when integrated into bumper components.
Innovation Solution
The solution involves a signal generating device that produces a modulated periodic oscillation signal for improved noise suppression, using techniques like Barker or Gold codes, and a correlation unit that evaluates echo signals by cross-correlating them with the transmitted signal, allowing for reliable environment monitoring without significant additional hardware or design changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Shape
If ultrasonic transducers are installed in a concealed manner within the bumper, then the aesthetic appearance and aerodynamic properties are improved, but the signal-to-noise ratio deteriorates due to increased noise interference and signal attenuation
Solution Approach 1:
The patent applies preliminary action by pre-modulating the transmitted ultrasonic signal with a known code sequence (such as Barker code or Gold code) before transmission. This allows the receiver to perform correlation processing with the known code, effectively suppressing noise and interference that enters during transmission through the bumper wall, thus improving signal-to-noise ratio while maintaining concealed installation
Solution Approach 2:
The patent changes the signal parameters by using modulated periodic oscillation signals with specific code sequences instead of simple continuous waves. The modulation code provides a unique fingerprint that enables correlation-based noise suppression, allowing the system to distinguish the transmitted signal from noise introduced by the concealed installation structure
2Measurement precision
If complex signal processing techniques are implemented to suppress noise, then the measurement precision is improved, but the device complexity and cost increase
Solution Approach 1:
The patent implements feedback by using the known transmitted code sequence as a reference for correlation processing. The receiver correlates the received signal with the stored reference code, and this feedback mechanism automatically suppresses noise and interference, improving measurement precision without requiring complex adaptive algorithms or additional hardware components
3Ease of manufacture
If the ultrasonic signal is transmitted through the bumper wall, then the concealed installation is achieved, but the signal attenuation increases reducing the monitoring range
Solution Approach 1:
By pre-modulating the signal with a known code sequence before transmission through the bumper, the system enables correlation processing at the receiver that compensates for signal attenuation. The correlation technique enhances the weak returned signal by matching it with the known transmitted code, thereby extending the effective monitoring range despite the bumper wall attenuation
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 enhances the signal-to-noise ratio and spatial resolution, enabling effective environment monitoring with reduced noise interference and system costs, while maintaining the sensors' concealment within the vehicle's structure.
Implementation Method 1
at least one ultrasonic transducer for converting electric oscillations into acoustic oscillations and/or vice versa
Implementation Method 2
the evaluation unit comprises a correlation unit which forms a cross-correlation of the transmitted signal with the received signal and is also constructed to determine the one or more distances from objects in the environment by means of the correlation signal calculated from the cross-correlation
Implementation Method 3
a signal generating device for generating a transmitted signal, particularly a modulated periodic oscillation signal
Data Source
AI summary
An environment monitoring device in a motor vehicle having a signal generating device for generating a transmitted signal, at least one ultrasonic transducer for converting electric oscillations into acoustic oscillations and/or vice versa, and an evaluation device which evaluates an electric received signal in order to determine distances to objects in an environment of the motor vehicle, wherein the signal generating device is linked to the at least one ultrasonic transducer so that the ultrasonic transducer emits an ultrasonic transmitted signal into the environment in accordance with the electric transmitted signal, and the evaluation device is connected to the at least one ultrasonic transducer or at least one further ultrasonic transducer in order to receive the electric received signal. Also disclosed is a method for monitoring an environment by using a cross-correlation.