In the underwater visible light communication (VLC) system, the single-photon avalanche diode (SPAD) can expand communication distance. However, the output signals from practical SPADs under dead time limit are not Poisson distributed. In this paper, the generalized likelihood block detection (GLBD) receiver is developed for practical SPAD-based underwater VLC system with on–off keying modulation. The proposed receiver can detect the data sequence without any prior knowledge of the channel and the background radiation. Correspondingly, a fast search algorithm for GLBD receiver is also proposed. In addition, a block coding scheme is utilized to solve the error floor problem. Simulation results show that the bit error rate (BER) performance of the proposed receiver is closer to the BER low bound compared to the existing receiver. Moreover, the fast search algorithm reduces the computational complexity without any performance loss.

中文翻译：

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基于SPAD的水下VLC系统的广义似然块检测

在水下可见光通信（VLC）系统中，单光子雪崩二极管（SPAD）可以扩大通信距离。然而，实际SPAD 在死区时间限制下的输出信号不是泊松分布的。在本文中，广义似然块检测 (GLBD) 接收器是为具有开关键控调制的基于 SPAD 的实际水下 VLC 系统开发的。所提出的接收器可以检测数据序列，而无需任何信道和背景辐射的先验知识。相应地，还提出了一种GLBD接收机的快速搜索算法。此外，使用块编码方案来解决错误底线问题。仿真结果表明，与现有接收器相比，所提出接收器的误码率 (BER) 性能更接近 BER 下限。而且，