可见光通信色移键控星座设计方法研究

Research on design method for color shift keying constellation

本文提出一种基于色移键控(CSK)调制兼容照明的可见光通信(VLC)系统星座图设计方法,可实现多色光源在通信的同时保证色度和视觉亮度稳定。基于国际照明委员会(CIE)1931 XYZ色度系统,本文给出了色度和亮度约束在CSK星座布局优化问题的数学表达式。进一步的本文提出采用数值优化中的内点法对该问题进行求解。由于内点法要求目标函数可微,本文提出一种局部近似的方法将CSK星座优化问题的目标函数连续化。此外,内点法要求算法的起始点严格可行,本文提出了一种候选点生成方法。实验表明,本文所提出的设计方法能够应用于基于商业发光二极管(LED)的CSK-VLC系统的星座图设计。

In this paper,a constellation design method for illumination compatible visible light communication(VLC)system based on color shift keying(CSK)modulation and is proposed,which can ensure the stability of chromaticity and visual brightness while communicating using multi-color light sources.Based on CIE 1931 XYZ chroma system,this paper presents the mathematical expressions of the chromaticity and luminance constraints in CSK constellation layout optimization problem.Furthermore,the interior point method is proposed to solve the problem.Since the interior point method requires the objective function to be differentiable,a local approximation method is proposed to make the objective function of CSK constellation optimization problem continuous.In addition,the interior point method requires that the starting point of the algorithm is strictly feasible.In this paper,a candidate point generation method is proposed to solve the problem.Experimental results show that the proposed design method can be applied to the constellation design of CSK-VLC system based on commercial light-emitting diodes(LED).