LIDAR Signal Acquisition via Multi-Channel ADC Coupling
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current LIDAR systems face limitations in generating high-resolution 3-D point clouds due to low pulse repetition rates and saturation issues, which affect imaging resolution and range, particularly in applications requiring broad fields of view and rapid image updates.
Innovation Solution
The system combines return signals from multiple LIDAR channels onto a single analog-to-digital converter, using DC coupling, adjusted bias voltages based on temperature, and a multiplexer to enhance measurement throughput and consistency, improving signal quality and power management.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Area of stationary object
If a single laser emitter/detector combination with beam path alteration (mirror, prism, or actuation) is used to achieve broader field of view, then the field of view is improved, but the point cloud density decreases due to limitations on pulse repetition rate
Solution Approach 1:
The system divides the single beam path into multiple independent emitter/detector channels, each capable of operating at full pulse repetition rate. This segmentation allows simultaneous coverage of multiple angular positions without sacrificing point cloud density in any single direction, as each channel operates independently at maximum throughput.
Solution Approach 2:
Multiple emitter/detector channels are merged into a unified LIDAR system that combines their individual point clouds into a comprehensive 3-D representation. This merging approach achieves broader effective field of view while maintaining high point cloud density by aggregating data from multiple high-rate channels.
2Productivity
If multiple emitter/detector channels are used to increase pixels generated per unit time, then imaging resolution and range are improved, but device complexity increases
Solution Approach 1:
Multiple emitter/detector channels share common control electronics, signal processing circuits, and data processing architecture. This multi-functionality allows the system to achieve high productivity through parallel channels while reducing overall device complexity by eliminating redundant components and leveraging shared resources across all channels.
3Productivity
If high pulse repetition rates are used to increase measurement throughput, then productivity is improved, but saturation issues occur affecting imaging resolution and range
Solution Approach 1:
The system segments the measurement task across multiple channels, each operating at high pulse repetition rates. By distributing the total measurement load across parallel channels rather than overloading a single channel, the system maintains high overall throughput while preventing saturation in individual detectors, thereby preserving measurement precision and imaging resolution.
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 increases the number of pixels generated per unit time, enhancing imaging resolution and range while reducing power consumption and overheating, enabling more accurate and timely 3-D environmental scanning.
Implementation Method 1
A portion of the light reflects from the object and returns to a detector of the LIDAR system
Implementation Method 2
In some examples, pulses of light are generated by a laser emitter
Implementation Method 3
The light pulses are focused through a lens or lens assembly
Implementation Method 4
Based on the time elapsed between emission of the pulse of light and detection of the returned pulse of light, a distance is estimated
Data Source
AI summary
Methods and systems for combining return signals from multiple channels of a LIDAR measurement system are described herein. In one aspect, the outputs of multiple receive channels are electrically coupled before input to a single channel of an analog to digital converter. In another aspect, a DC offset voltage is provided at the output of each transimpedance amplifier of each receive channel to improve measured signal quality. In another aspect, a bias voltage supplied to each photodetector of each receive channel is adjusted based on measured temperature to save power and improve measurement consistency. In another aspect, a bias voltage supplied to each illumination source of each transmit channel is adjusted based on measured temperature. In another aspect, a multiplexer is employed to multiplex multiple sets of output signals of corresponding sets of receive channels before analog to digital conversion.