This letter proposes an analytical model on the energy efficiency for visible light communications (VLC) based on light-emitting diode (LED). We certify the variation pattern of energy efficiency of LEDs follows the second-order system rather than the first-order system like the LED's frequency response. This pattern means considerable power loss in the VLC transmission, which should be taken care of when designing VLC systems. This letter demonstrates a series of simulations and experiments to prove this viewpoint's accuracy. Moreover, by comparing the experimental results, we analyze the influence of LED's parasitic parameters on energy efficiency. Furthermore, a linear LED equivalent circuit model is given for the high modulation bandwidth application. We test it by calculating its decisive coefficients according to different LEDs' experimental results.

中文翻译：

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高调制带宽发光二极管的能效分析


这封信提出了一种基于发光二极管（LED）的可见光通信（VLC）能效的分析模型。我们证明LED的能效变化模式遵循二阶系统，而不是像LED的频率响应那样遵循一阶系统。这种模式意味着 VLC 传输中会有相当大的功率损耗，在设计 VLC 系统时应注意这一点。这封信展示了一系列的模拟和实验来证明这一观点的准确性。此外，通过比较实验结果，我们分析了LED寄生参数对能效的影响。此外，针对高调制带宽应用给出了线性 LED 等效电路模型。我们根据不同LED的实验结果，计算其决定系数来进行测试。