Abstract. We present a state-of-the-art ultraviolet (UV)-based multiuser indoor communication over power-constrained discrete-time Poisson channels. To adhere to the UV exposure limit and safety, we consider a low-power transmission regime where strict peak and average transmit power constraints are imposed. These constraints are different from conventional electrical power constraints. Therefore, performance metrics, such as bit error rate (BER) and channel capacity, are newly characterized in relation to the discrete-time Poisson channel. We develop a minimum mean-square error receiver to reject the interference from multiple users with a detection scheme robust against channel state information (CSI) uncertainty. Furthermore, a downlink beamforming optimization problem is formulated using a second-order cone program to maximize the received signal-to-interference-plus-noise ratio. We bound the behavior of the mutual information in the low-power regime, when dark current increases linearly with average transmit power. In addition, the power penalty of multiuser link is analyzed. The proposed system is also realized in the experiment. The influence of the control parameter, i.e., average-to-peak power ratio, on the BER relative to the peak transmit power is experimentally investigated. The experimental results are found consistent with the theoretical simulation results. Further, from the simulation results, it is found that the proposed system approaches the CSI lower bound performance with a minimum sequence length and can provide ubiquitous link connectivity in indoor applications while keeping network structure and management simple.

中文翻译：

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功率受限离散时间泊松​​信道上最先进的紫外线多用户室内通信

摘要。我们提出了一种基于功率受限离散时间泊松​​信道的最先进的基于紫外线 (UV) 的多用户室内通信。为了遵守紫外线照射限制和安全性，我们考虑了一种低功率传输机制，其中强加了严格的峰值和平均传输功率限制。这些约束不同于传统的电力约束。因此，性能指标，例如误码率 (BER) 和信道容量，是与离散时间泊松​​信道相关的新特性。我们开发了一种最小均方误差接收器，以通过对信道状态信息 (CSI) 不确定性具有鲁棒性的检测方案来拒绝来自多个用户的干扰。此外，使用二阶锥程序来制定下行链路波束成形优化问题，以最大化接收到的信号与干扰加噪声比。当暗电流随平均发射功率线性增加时，我们限制了低功率状态下互信息的行为。此外，还分析了多用户链路的功率损失。所提出的系统也在实验中得以实现。通过实验研究了控制参数，即平均峰值功率比对 BER 相对于峰值发射功率的影响。实验结果与理论模拟结果一致。此外，从模拟结果来看，