Lidar Inter-pulse Timing Sequence for External Pulse Filtering
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lidar systems for autonomous driving and advanced driver assistance systems face interference from other lidar systems, leading to false detections and reduced performance due to the inability to distinguish between self-emitted and external laser pulses.
Innovation Solution
A lidar system that emits sequences of laser pulses with defined inter-pulse timing, allowing the control unit to verify the consistency of reflections by detecting the same inter-pulse timing, thereby filtering out external pulses and improving performance and robustness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If a lidar system operates in an environment with multiple active lidar systems, then the coverage and functionality of the system are improved, but the reliability deteriorates due to interference from external laser pulses causing false detections
Solution Approach 1:
The patent applies periodic action by using sequences of laser pulses with defined inter-pulse timing. The control unit emits multiple pulses in a sequence rather than single isolated pulses, and the detector is configured to detect reflections with the same inter-pulse timing pattern. This periodic emission pattern allows the system to distinguish between self-emitted pulses (which follow the known timing sequence) and external interference pulses (which do not match the timing pattern), thereby resolving the contradiction between operating in multi-lidar environments and maintaining detection reliability
Solution Approach 2:
The patent implements feedback by having the control unit verify the consistency of detected reflections against the known inter-pulse timing of emitted sequences. The detector receives reflections and provides timing information back to the control unit, which then determines whether the reflections match the expected timing pattern. This feedback mechanism enables the system to filter out false detections caused by external interference while maintaining the ability to operate in environments with multiple active lidar systems
2Reliability
If the lidar system uses sequences of laser pulses with defined inter-pulse timing to filter external pulses, then the reliability is improved, but the device complexity increases due to additional control mechanisms
Solution Approach 1:
The patent uses periodic action in a simplified form by implementing regular sequences of laser pulses with fixed inter-pulse timing. Rather than complex variable timing patterns, the system employs consistent periodic emission that is easy to generate and verify. The control unit stores the known inter-pulse timing values and simply compares detected reflection timings against these predefined values, achieving reliable interference filtering without requiring complex control logic or additional hardware components
Solution Approach 2:
The patent applies parameter changes by utilizing the inter-pulse timing characteristic as a distinguishing parameter. Instead of changing physical hardware or adding complex processing mechanisms, the system changes the temporal parameter (timing interval) of the laser pulses and uses this parameter variation to identify and filter external interference. The control unit determines whether detected reflections have the same inter-pulse timing as the emitted sequences, providing a simple yet effective method to improve reliability while maintaining relatively simple device architecture
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
Enhances the lidar system's ability to differentiate between true and false detections, increasing its reliability and dynamic range for accurate time-of-flight measurements in the presence of interference.
Implementation Method 1
a control unit configured to perform time-of-flight measurements on said laser pulses and the detected reflections
Implementation Method 2
at least one detector configured to detect reflections of said laser pulses
Data Source
Figure 1~2
Figure 3~4
AI summary
The invention relates to a lidar system (10) comprising at least one laser source (11) configured to emit laser pulses (15) and to direct said laser pulses (15) in a field of view (16), at least one detector (13) configured to detect reflections (17) of said laser pulses (15), and a control unit (14) configured to perform time-of-flight measurements on said laser pulses (15) and the detected reflections (17). The control unit (14) is configured to control the at least one laser source (11) to emit sequences of laser pulses (15) with at least two sequential laser pulses (15) with a defined inter-pulse timing, wherein the at least one detector (13) is adapted to detect the inter-pulse timing (20) of the reflections (17) of said laser pulses (15), wherein the control unit (14) is configured to determine whether the detected reflections (17) have the same inter-pulse timing (20) as the at least two sequential laser pulses (15).