Optical wireless communication (OWC) using intensity-modulation and direct-detection (IM/DD) has a channel model which possesses unique features, due to the constraints imposed on the channel input. The aim of this tutorial is to overview results on the capacity of IM/DD channels with input-independent Gaussian noise as a model of OWC channels. It provides the reader with an entry point to the topic, and highlights some major contributions in this area. It begins with a discussion on channel models and how this IM/DD Gaussian channel model comes about, in addition to an explanation of input constraints. Then, it discusses the capacity of the single-input single-output channel, its computation, and capacity bounds and asymptotic capacity results. Then, it extends the discussion to the multiple-input multiple-output setup, and reviews capacity bounds for this channel model. Finally, it discusses multi-user channels modelled as a broadcast channel (downlink) or a multiple-access channel (uplink), with their associated capacity bounds.

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关于强度调制直接检测高斯光无线通信信道的容量：教程

由于对通道输入施加的限制，使用强度调制和直接检测 (IM/DD) 的光无线通信 (OWC) 具有具有独特特征的通道模型。本教程的目的是概述具有输入独立高斯噪声的 IM/DD 通道容量的结果，作为 OWC 通道的模型。它为读者提供了该主题的切入点，并突出了该领域的一些主要贡献。除了对输入约束的解释外，它首先讨论了通道模型以及这种 IM/DD 高斯通道模型是如何产生的。然后，讨论了单输入单输出通道的容量、计算、容量界限和渐近容量结果。然后，将讨论扩展到多输入多输出设置，并审查此渠道模型的容量界限。最后，它讨论了被建模为广播信道（下行链路）或多址信道（上行链路）的多用户信道及其相关的容量界限。