Switchable Local Oscillator Signals for Low-Noise LIDAR Detection

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Conventional LIDAR systems face issues with optical power drain and noise due to concurrent provision of first and second local oscillator signals to each pixel, leading to weaker signal-to-noise ratio and increased optical noise.

Innovation Solution

A local oscillator module is configured to selectively provide first and second local oscillator signals to a single LIDAR pixel at a time, allowing simultaneous transmission of a transmit beam, thereby reducing optical power consumption and noise.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Adaptability or versatility

If first and second local oscillator signals are provided concurrently to each pixel, then polarization diversity reception is achieved, but optical power drain increases and optical noise increases

Engineering Contradiction:

Improvepolarization diversity receptionVSAvoidoptical power drain

Core Design Contradiction:

Adaptability or versatilityVSLoss of energy

Solution Approach 1:

The patent implements time-division multiplexing where the local oscillator module alternates between providing the first local oscillator signal and the second local oscillator signal to each LIDAR pixel in sequential time slots rather than concurrently. This periodic switching approach maintains polarization diversity reception capability while reducing instantaneous optical power consumption at each pixel, directly resolving the technical contradiction between adaptability and energy loss.

Inventive Principle:

Principle #19Periodic action

2Adaptability or versatility

If first and second local oscillator signals are provided concurrently to each pixel, then polarization diversity reception is achieved, but signal-to-noise ratio decreases

Engineering Contradiction:

Improvepolarization diversity receptionVSAvoidsignal-to-noise ratio

Core Design Contradiction:

Adaptability or versatilityVSMeasurement precision

Solution Approach 1:

By implementing time-division multiplexing with periodic switching between the first and second local oscillator signals, the patent eliminates simultaneous signal interference that degrades signal-to-noise ratio. Each pixel receives one oscillator signal at a time, allowing clean beat signal generation with higher signal-to-noise ratio, while the sequential sampling across multiple pixels maintains polarization diversity reception capability.

Inventive Principle:

Principle #19Periodic action

3Adaptability or versatility

If first and second local oscillator signals are provided concurrently to each pixel, then polarization diversity reception is achieved, but optical noise increases

Engineering Contradiction:

Improvepolarization diversity receptionVSAvoidoptical noise

Core Design Contradiction:

Adaptability or versatilityVSObject-generated harmful factors

Solution Approach 1:

The patent employs periodic time-division multiplexing where the local oscillator module switches between providing the first local oscillator signal and the second local oscillator signal to different LIDAR pixels at different time slots. This approach prevents simultaneous optical signal interference that generates noise, reducing overall optical noise levels while maintaining the ability to receive both polarization orientations through sequential measurement.

Inventive Principle:

Principle #19Periodic action

4Loss of energy

If local oscillator signals are switched between multiple pixels, then optical power consumption is reduced, but system complexity increases

Engineering Contradiction:

Improveoptical power consumptionVSAvoidsignal switching mechanism

Core Design Contradiction:

Loss of energyVSDevice complexity

Solution Approach 1:

The local oscillator module is designed as a universal signal distribution unit that can dynamically switch between providing the first local oscillator signal and the second local oscillator signal to multiple different LIDAR pixels. This multi-functional design allows a single module to serve multiple pixels sequentially, reducing overall system complexity compared to having dedicated oscillators for each pixel, while achieving reduced optical power consumption.

Inventive Principle:

Principle #6Universality (Multi-functionality)

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 signal-to-noise ratio and reduces optical noise, resulting in more accurate LIDAR imaging and improved autonomous vehicle control.

Implementation Method 1

a first receiver configured to receive (i) a first polarization orientation of the return beam; and (ii) the first local oscillator signal from local oscillator module; and a second receiver configured to receive (i) a second polarization orientation of the return beam; and (ii) the second local oscillator signal from the local oscillator module

Methodology Applied

Scientific EffectCoherent detection: Homodyne Detection

Data Source

PatentUS12461243B2Lidar with switchable local oscillator signals

Publication Date: 2025.11.04 AURORA OPERATIONS INC

AI summary

A light detection and ranging (LIDAR) sensor system includes a plurality of LIDAR pixels and a local oscillator module. The local oscillator module is coupled to the plurality of LIDAR pixels. The local oscillator module includes a first local oscillator input configured to receive a first local oscillator signal and a second local oscillator input configured to receive a second local oscillator signal. The local oscillator module is configured to provide the first local oscillator signal or the second local oscillator signal to a first LIDAR pixel of the plurality of LIDAR pixels.