The bandwidth upgrade required in short-reach optical communications has prompted the need for detection schemes that combine field reconstruction with a cost-effective subsystem architecture. Here we propose an asymmetric self-coherent detection (ASCD) scheme for the field reconstruction of self-coherent (SC) complex double-sideband (DSB) signals based on a direct-detection (DD) receiver with two reception paths. Each reception path consists of a photodiode (PD) and an analog-to-digital converter for the detection of a part of the received optical signal that experiences a different optical transfer function via the configuration of an optical filter. We derive an analytical solution to reconstructing the signal field and show the optimal filter response in optimizing the signal SNR. Further, we numerically characterize the theoretical performance of a specific ASCD scheme based on a chromatic dispersion filter and validate the principle of the ASCD scheme in a proof-of-concept experiment. The ASCD scheme approaches the electrical spectral efficiency of coherent detection with a cost-effective DD receiver, which shows the potential for high-speed short-reach links required by edge cloud communications and mobile X-haul systems.

中文翻译：

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非对称自相干检测

短距离光通信所需的带宽升级促使需要将场重建与具有成本效益的子系统架构相结合的检测方案。在这里，我们提出了一种非对称自相干检测 (ASCD) 方案，用于基于具有两个接收路径的直接检测 (DD) 接收器的自相干 (SC) 复双边带 (DSB) 信号的场重建。每条接收路径都由一个光电二极管 (PD) 和一个模数转换器组成，用于检测接收到的光信号的一部分，该信号通过滤光器的配置经历不同的光传递函数。我们推导出了重构信号场的解析解，并显示了优化信号 SNR 的最佳滤波器响应。更远，我们对基于色散滤波器的特定 ASCD 方案的理论性能进行了数值表征，并在概念验证实验中验证了 ASCD 方案的原理。ASCD 方案通过具有成本效益的 DD 接收器接近相干检测的电频谱效率，这显示了边缘云通信和移动 X 传输系统所需的高速短距离链路的潜力。