To optimize the uniformity of signal-to-noise ratio (SNR) distribution in a visible light communication (VLC) system, the firefly algorithm is improved for joint optimization of location, power allocation and orientation of a light-emitting diode (LED) lamp array. Taking 16 LED lamps as an example, optimizations with a different number of degrees-of-freedom (DOF) are investigated. The orientation-involved optimizations significantly decrease average SNR and average illuminance. However, if the average illuminance is restricted to a large value, the effects of the orientation DOF would be small. With the restriction of illuminance, the optimization with all the three DOFs gives an improvement of 4.18 times in SNR uniformity, compared to the typical square-circle layout. The optimizations are further studied by varying the number of LED lamps.

中文翻译：

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使用萤火虫算法优化可见光通信系统中照明灯的位置，功率分配和方向

为了优化可见光通信（VLC）系统中的信噪比（SNR）分布的均匀性，改进了萤火虫算法，以共同优化发光二极管（LED）灯的位置，功率分配和方向大批。以16个LED灯为例，研究了不同自由度（DOF）的优化。涉及方向的优化显着降低了平均SNR和平均照度。但是，如果将平均照度限制为较大的值，则定向自由度的影响将很小。在照度的限制下，与典型的方形圆圈布局相比，所有三个自由度的优化均使SNR均匀性提高了4.18倍。通过改变LED灯的数量进一步研究优化。