Visible Light Communication Transmitter Chromaticity Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Visible light communication systems face challenges in compensating for non-linear distortion caused by light sources and receiving devices, which affects demodulation accuracy and increases error rates due to the complexity of existing distortion compensation methods.
Innovation Solution
A visible light communication system that includes a transmitter emitting light with chromaticities corresponding to all modulation coordinates and a receiver setting specific chromaticity coordinates based on received light, allowing for demodulation accuracy improvement and error rate reduction without complex circuit configurations.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If conventional distortion compensation methods are used, then demodulation accuracy can be improved, but device complexity increases
Solution Approach 1:
The patent applies preliminary action by transmitting training signals containing chromaticity coordinate information before actual data communication. The receiver uses this pre-transmitted information to establish the correct chromaticity coordinates for demodulation, eliminating the need for complex real-time distortion compensation circuits while maintaining high demodulation accuracy.
Solution Approach 2:
The patent implements feedback by having the transmitter send training signals with known chromaticity coordinates, allowing the receiver to verify and adjust its demodulation parameters based on the actual received chromaticity values. This feedback mechanism enables accurate demodulation without requiring complex distortion compensation circuitry.
2Reliability
If complex distortion compensation processes are applied, then error rate decreases, but processing time increases
Solution Approach 1:
The patent reduces processing time by performing distortion compensation in advance through the transmission of training signals. The chromaticity coordinate information is established beforehand, allowing the receiver to directly use this pre-computed data for demodulation without performing complex real-time calculations, thus reducing error rates while minimizing processing time.
Solution Approach 2:
The patent uses copying by transmitting training signals that replicate the chromaticity coordinate information under controlled conditions. The receiver copies this information to establish the correct demodulation parameters, avoiding the need for complex real-time distortion analysis and significantly reducing processing time while maintaining reliability.
3Measurement precision
If real-time distortion compensation is performed, then demodulation accuracy improves, but power consumption increases
Solution Approach 1:
The patent reduces power consumption by performing distortion compensation calculations in advance during the transmission of training signals. The receiver uses the pre-established chromaticity coordinate information for demodulation, eliminating the need for continuous complex calculations during data transmission and significantly reducing power consumption while maintaining high demodulation accuracy.
Solution Approach 2:
The patent minimizes power consumption by copying chromaticity coordinate information from training signals rather than performing real-time distortion compensation calculations. This copying approach allows the receiver to use pre-computed data for demodulation, reducing the computational load and associated power consumption while maintaining accurate demodulation.
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
The proposed system effectively compensates for non-linear distortion, enhancing demodulation accuracy and reducing error rates while simplifying the circuit design and reducing power consumption.
Implementation Method 1
extensive research has been conducted to realize a very convenient communication environment (a visible light communication system) utilizing indoor and outdoor lighting devices. Considering influence on human bodies and medical equipment, LED is the most promising candidate as a lighting device for optical communication.
Implementation Method 2
a light receiving device receives light emitted from a plurality of light sources of a transmitter, a coordinate setter sets coordinate information representing predetermined chromaticity coordinates based on chromaticities of received light
Data Source
AI summary
A transmitter in a visible light communication system is provided, in which a plurality of light sources emit light in different colors, a data converter converts data to predetermined chromaticity coordinates, a data transmitter emits light having a chromaticity corresponding to the chromaticity coordinates by controlling light intensity of each of the light sources, and a pre-light emitter emits light having chromaticities corresponding to all chromaticity coordinates by controlling the light intensity of each of the light sources, before the light intensity control of the data transmitter.