Abstract In visible light communication (VLC) under weak illuminance, the single-photon avalanche diode (SPAD) is usually utilized for signal detection due to its high sensitivity to optical signals. However, the SPAD detector suffers from the nonlinearity effect induced by the dead time, which degrades the performance of the classical constellation and signal detection schemes. In this paper, in consideration of the nonlinear dead time effect, a novel reordering Anscombe Root transformation (ART) based detector is proposed for the SPAD VLC systems employing pulse–amplitude modulation (PAM). In addition, a geometric PAM (Geo-PAM) constellation is designed to further enhance the performance. Simulation results demonstrate that, the proposed detector and Geo-PAM constellation are capable of widening the working region of SPAD, where the BER is lower than 1 0 − 3 , in comparison with its classical counterparts.

中文翻译：

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在非线性失真下为 SPAD VLC 系统重新排序基于 ART 的检测器和 Geo-PAM 星座设计

摘要 在弱照度下的可见光通信（VLC）中，单光子雪崩二极管（SPAD）由于对光信号具有较高的灵敏度，因此常被用于信号检测。然而，SPAD检测器受到死区时间引起的非线性效应的影响，这降低了经典星座和信号检测方案的性能。在本文中，考虑到非线性死区时间效应，为采用脉冲幅度调制 (PAM) 的 SPAD VLC 系统提出了一种基于重新排序 Anscombe Root 变换 (ART) 的新型检测器。此外，还设计了几何PAM（Geo-PAM）星座以进一步提升性能。仿真结果表明，所提出的探测器和 Geo-PAM 星座能够拓宽 SPAD 的工作区域，