基于多色LED的可见光通信联合调制技术

[摘要] 提出了一种针对广义色移键控（CSK）调制RGB 3色发光二极管（LED）的可见光通信（VLC）星座图设计方法。为了实现通信与照明的结合，考虑了一些照明条件的约束：首先，LED产生的颜色和强度被限制以达到照明要求；其次，为了减小非线性效应的影响，每盏LED灯的功率被限制在线性范围；最后，利用奇异值分解（SVD）的预均衡来消除多径效应的影响和颜色间的干扰。仿真结果表明，相比较于每路LED分别采用开关键控（OOK）调制的误码率，优化的星座图性能更优。

[关键词] 可见光通信；星座图设计；多色发光二极管；色移键控

[Abstract] In this paper, we propose a constellation design that uses RGB LEDs modulated by generalized color-shift keying (CSK) modulation to realize visible light communication (VLC). To achieve joint communication and illumination, we consider constraining some lighting conditions. First, the average color and power are constrained to meet the lighting requirements. Second, to minimize nonlinear effects, the power of each LED is constrained in its linear range. Third, a singular value decomposition (SVD)-based pre-equalizer is employed to mitigate the effects of multi-path and cross-talk between colors. Simulation results show that the bit-error rate of the proposed scheme is lower than that of a conventional scheme where OOK is used for each branch.

[Keywords] optical wireless communication; constellation design; multicolor LED; color shift keying