Improved Target Signal Source Tracking and Extraction Method Based on Outdoor Visible Light Communication Using a...

Area of Science:

• Optical Communications
• Computer Vision
• Signal Processing

Background:

• Outdoor Visible Light Communication (OVLC) systems require accurate tracking of signal sources (LEDs) for data transmission.
• Existing Visible Light Communication (VLC) research often overlooks the initial step of signal source extraction, particularly in dynamic outdoor environments.
• Challenges in outdoor VLC include moving transmitters/receivers and environmental interference, hindering system feasibility.

Purpose of the Study:

• To develop an improved tracking algorithm for accurately extracting the target Light Emitting Diode (LED) signal source region in dynamic outdoor scenes.
• To enhance the robustness and accuracy of tracking algorithms for image-sensor-based VLC systems operating in complex environments.
• To address the critical first step of communication realization in OVLC by improving target LED extraction.

Main Methods:

• An improved Cam-Shift algorithm incorporating a Kalman filter is proposed for tracking.
• The algorithm utilizes color and spatial distribution characteristics of the target LED.
• It employs adaptive search window adjustment and motion prediction based on position and velocity information.

Main Results:

• The proposed algorithm achieved a tracking error of 0.85 cm.
• The computational time for processing a single frame was 0.042 seconds.
• The algorithm successfully extracted the target LED area accurately, even with multiple interference factors.

Conclusions:

• The developed algorithm effectively extracts target LED regions in dynamic and interfered outdoor environments.
• This advancement facilitates the initial communication step in image-sensor-based OVLC systems.
• The study lays the groundwork for subsequent data transmission and other functionalities in OVLC.