The terahertz band has been recognized as a promising candidate to support future rate-greedy applications such as 6G communications. Optoelectronic terahertz communications are beneficial for the realization of high-speed transmission. In this Letter, we propose and experimentally demonstrate an optoelectronic terahertz transmission system with intensity modulation and direct detection, where a discrete multitone (DMT) waveform with high-order quadrature amplitude modulation (QAM) is used. A zero-bias diode (ZBD) is used in the system as a simple, cost-effective direct detection terahertz receiver. A nonlinearity-aware digital signal reception routine is proposed to mitigate the nonlinear impairments induced by subcarrier-to-subcarrier beating interference from the ZBD. In this experiment, up to a 60 Gbit/s line rate 16QAM-DMT signal is successfully transmitted over a 3 m wireless link in the 310 GHz band, and the mean signal-to-noise ratio is improved by 3 dB with nonlinearity-aware signal processing routine. The advantageous features of such a scheme make it a promising solution for terahertz wireless communications.

中文翻译：

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具有零偏置二极管的非线性感知光电太赫兹离散多音信号传输。

太赫兹频段已被公认为是支持未来速率贪婪应用（例如6G通信）的有前途的候选者。光电太赫兹通信有利于实现高速传输。在这封信中，我们提出并通过实验演示了具有强度调制和直接检测功能的光电太赫兹传输系统，其中使用了具有高阶正交幅度调制（QAM）的离散多音（DMT）波形。系统中使用零偏二极管（ZBD）作为简单，经济高效的直接检测太赫兹接收器。提出了一种非线性感知数字信号接收例程，以减轻由ZBD的子载波到子载波的跳动干扰引起的非线性损伤。在这个实验中 高达60 Gbit / s的线速16QAM-DMT信号已在310 GHz频带的3 m无线链路上成功传输，并且通过具有非线性感知功能的信号处理程序，平均信噪比提高了3 dB。这种方案的有利特征使其成为太赫兹无线通信的有希望的解决方案。