The paper provides a new perspective on peak- and average-constrained Gaussian channels. Such channels model optical wireless communication (OWC) systems which employ intensity-modulation with direct detection (IM/DD). First, the paper proposes a new, capacity-preserving vector binary channel (VBC) model, consisting of dependent binary noisy bit-pipes. Then, to simplify coding over this VBC, the paper proposes coding schemes with varying levels of complexity, building on the capacity of binary-symmetric channels (BSC) and channels with state. The achievable rates are compared to capacity and capacity bounds, showing that coding for the BSC with state over the VBC achieves rates close to capacity at moderate to high signal-to-noise ratio (SNR), whereas simpler schemes achieve lower rates at lower complexity. The presented coding schemes are realizable using capacity-achieving codes for binary-input channels, such as polar codes. Numerical results are provided to validate the theoretical results and demonstrate the applicability of the proposed schemes.

翻译：本文为具有峰值与平均约束的高斯信道提供了全新视角。此类信道可建模采用强度调制直接检测（IM/DD）的光学无线通信（OWC）系统。首先，论文提出一种保持容量的矢量二进制信道（VBC）模型，该模型由相互依赖的二进制噪声比特管道构成。为简化该VBC上的编码过程，论文基于二进制对称信道（BSC）及带状态信道的容量特性，设计了具有不同复杂度等级的编码方案。将可达到的传输速率与信道容量及容量界进行对比，结果表明：在VBC上采用针对带状态BSC设计的编码方案，可在中高信噪比（SNR）下逼近信道容量；而更简单的方案虽可降低复杂度，但所能达到的速率较低。所提出的编码方案可利用针对二进制输入信道的容量逼近码（如极化码）实现。最后通过数值结果验证理论分析的正确性，并证明所提方案的适用性。