LED Sub-Array Switching for Visible Light Communication
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing Visible Light Communication (VLC) systems are complex and costly, requiring entire LED diode strings to be modulated for communication, which increases heat and complexity in lighting fixtures, making them expensive and inefficient.
Innovation Solution
A light fixture design that includes a sub-array and an alternate array of light-emitting elements, coupled with respective switch elements and a control circuit, allowing selective power switching between the arrays to generate modulated communication signals without burdening the electronic ballast with high frequency switching, using different intensity, color temperature, or frequency for VLC communication.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If the entire LED diode string is modulated for VLC communication, then communication capability is achieved, but device complexity and cost increase
Solution Approach 1:
The LED diode string is divided into multiple independently controllable segments or groups. Instead of modulating the entire string for VLC, only specific segments are modulated while others continue providing illumination. This segmentation allows VLC communication functionality to be achieved without requiring modification of the entire lighting system, thereby reducing device complexity and cost.
2Adaptability or versatility
If the entire LED diode string is modulated for VLC communication, then communication capability is achieved, but heat generation increases
Solution Approach 1:
By segmenting the LED string into illumination portions and communication portions, only specific segments are modulated for VLC. This reduces the overall power consumption and heat generation compared to modulating the entire string, as fewer LEDs are actively switching for communication purposes while others maintain steady illumination.
Solution Approach 2:
Instead of applying full modulation across the entire LED string, the invention applies partial modulation only to specific segments sufficient for VLC communication. This partial action achieves the communication capability without the excessive heat generation that would result from modulating all LEDs at high frequency.
3Adaptability or versatility
If separate power supplies are added for VLC operation, then communication capability is achieved, but cost increases
Solution Approach 1:
The existing power supply and driver circuitry of the lighting fixture is designed to perform dual functions: providing power for illumination and enabling VLC communication through selective modulation of LED segments. This multi-functionality eliminates the need for separate dedicated power supplies for VLC, reducing both cost and device complexity while maintaining full communication capability.
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 reduces the complexity and cost of VLC systems, enabling communication without significantly affecting the illumination process and minimizing heat generation, allowing for flexible design and efficient VLC functionality within existing lighting fixtures.
Implementation Method 1
an array of light-emitting elements for generating light from the light fixture
Data Source
AI summary
A light fixture includes an array of light-emitting elements for generating light from the light fixture, and the array of light-emitting elements includes a defined sub-array of light-emitting elements. An alternate array of light-emitting elements is coupled in parallel with the defined sub-array of alternate light-emitting elements of the light emitter. Each of the sub-array and the alternate array are coupled with a respective switch element. A control circuit is coupled with the switch elements and configured for selectively switching power between the sub-array and the alternate array for modulating the operation of the sub-array and alternate array of light-emitting elements to generate modulated communication signals.