Oscillating Signal Envelope Reconstruction via Adaptive Sampling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing systems for reconstructing the envelope of oscillating signals, such as those from ultrasonic echoes, face challenges in accurately sampling signals due to unpredictable phase and frequency variations, leading to instability and the need for expensive high-speed sampling hardware.
Innovation Solution
A control arrangement that analyzes the oscillating signal to determine its frequency or period, allowing for scheduled sampling near peak deviations, enabling accurate envelope reconstruction without requiring high sampling rates or sophisticated hardware.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a diode peak detector is used to reconstruct the envelope signal, then the envelope can be obtained, but the negative slope of the original envelope is altered and the reconstructed signal becomes unstable
Solution Approach 1:
The patent replaces the mechanical/electrical diode peak detector system with a software-based envelope detection method. The control arrangement analyzes the oscillating signal and schedules sampling at optimal times without using a diode capacitor circuit, thereby eliminating the distortion of the negative slope and improving signal stability while maintaining envelope reconstruction accuracy
Solution Approach 2:
The patent changes the sampling strategy from fixed-rate sampling to adaptive sampling based on signal analysis. By determining the frequency or period of the oscillating signal and scheduling sampling at specific phases (near peak deviations), the system optimizes the sampling parameters to accurately capture the envelope without the instability introduced by diode peak detectors
2Measurement precision
If sampling is performed at a very high sampling rate to avoid aliasing effects, then accurate signal reconstruction is achieved, but sophisticated and expensive hardware is required
Solution Approach 1:
The control arrangement performs preliminary analysis of the oscillating signal to determine its frequency or period before sampling. This advance analysis allows the system to schedule sampling at optimal times (near peak deviations) without requiring continuous high-rate sampling, thereby reducing hardware requirements while maintaining reconstruction accuracy
Solution Approach 2:
The patent implements dynamic sampling where the sampling rate and timing are adjusted based on the analyzed signal characteristics. Instead of using a fixed high sampling rate that requires sophisticated hardware, the system dynamically schedules sampling at appropriate moments, reducing the need for expensive high-speed sampling hardware
3Device complexity
If fixed-rate sampling is used, then hardware implementation is simpler, but aliasing effects occur and envelope reconstruction becomes inaccurate
Solution Approach 1:
The control arrangement uses feedback from signal analysis to adjust sampling timing. By continuously analyzing the oscillating signal to determine frequency or period and using this information to schedule subsequent sampling at optimal phases, the system eliminates aliasing effects and improves envelope reconstruction accuracy without requiring complex high-speed hardware
Data Source
Figure 1~2(b)
Figure 3~4
Figure 5
AI summary
There is provided an apparatus comprising a control arrangement to analyse a portion of an oscillating signal to determine a value indicative of a frequency or at least a part of a period of the oscillating signal and to use said value to schedule sampling of the signal within a time period within a cycle of the oscillating signal, corresponding to a region around a maximum deviation from a reference value within that cycle, for obtaining a sample for reconstructing an envelope of the oscillating signal. The oscillating signal may be based on echoes of an ultrasonic waveform. The apparatus may be used in a vehicle parking assistance system.