LiDAR Echo Ranging Using Combined TDC and ADC Selection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing LiDAR systems face limitations in ranging performance due to time discrimination accuracy in TDC-based methods and sampling rate limitations in ADC-based methods, affecting overall precision and accuracy.
Innovation Solution
A combined TDC and ADC ranging method that processes echo signals to determine multiple data sets, selecting the best output based on relationships between transmit power, estimated distances, and signal parameters to enhance precision and accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If TDC-based ranging manner is used, then measurement accuracy is improved, but ranging performance is limited by time discrimination accuracy
Solution Approach 1:
The patent combines TDC and ADC ranging methods into a unified ranging system. The time discrimination circuit processes the echo signal to obtain time of flight data, while the ADC circuit converts the echo signal to digital signals for further processing. Both methods process the same echo signal and their results are integrated to overcome the limitations of each individual method, achieving both high measurement accuracy and reliable ranging performance.
Solution Approach 2:
The ranging system is designed to handle multiple ranging scenarios through a universal processing architecture. The system can adapt to different ranging conditions (short distance, long distance, high precision requirements) by flexibly utilizing both TDC and ADC methods, making the system multi-functional and universally applicable to various ranging needs without requiring separate systems for each scenario.
2Difficulty of detecting and measuring
If ADC-based ranging manner is used, then echo signal processing capability is improved, but ranging performance is limited by sampling rate
Solution Approach 1:
The patent merges ADC and TDC processing paths to compensate for the sampling rate limitation of ADC-based methods. While the ADC circuit provides robust echo signal processing and capability to handle low signal-to-noise ratio echoes, the TDC circuit provides high-precision time measurement. The combination allows the system to achieve both strong echo processing capability and high ranging precision, overcoming the sampling rate bottleneck.
3Device complexity
If single ranging manner is used, then system complexity is reduced, but ranging performance is affected by limitation factors
Solution Approach 1:
The patent integrates TDC and ADC ranging mechanisms into a single unified system that processes echo signals through both pathways simultaneously. The time discrimination circuit and ADC circuit work together to process the same echo signal, and their results are combined to produce the final ranging measurement. This integrated approach increases system complexity but eliminates the limitation factors present in single-method systems, achieving superior ranging performance across diverse scenarios.
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
Improves ranging precision and accuracy by flexibly combining TDC and ADC results, ensuring maximum accuracy through threshold-based selection and deletion of inaccurate data.
Implementation Method 1
A laser emits a light pulse that lasts a very short time period; a light transmission time period in which the light pulse reaches a target object from a LiDAR and then is reflected to a rangefinder from the target object is measured
Implementation Method 2
a received signal that is reflected from the target object with the transmitted detection signal
Data Source
AI summary
A ranging method and apparatus are provided. The method includes processing, by a ranging device, an echo signal of a detection signal based on a time-to-digital conversion ranging manner to determine a first data set. The echo signal is processed based on an analog-to-digital conversion ranging manner to determine a second data set. An output distance set is determined based on at least one parameter in the first data set or the second data set, and one or more of the following relationships: a relationship between at least one of an actual transmit power of the detection signal and a preset power threshold, a relationship between at least one estimated distance and a preset distance threshold, or a relationship between at least one signal parameter of the echo signal and a preset parameter threshold.