The current body of research on terahertz (THz) wireless communications predominantly focuses on its application for single-user backhaul/fronthaul connectivity at sub-THz frequencies. First, we develop a generalized statistical model for signal propagation at THz frequencies encompassing physical layer impairments, including random path-loss with Gamma distribution for the molecular absorption coefficient, short-term fading characterized by the $\alpha$-$\eta$-$\kappa$-$\mu$ distribution, antenna misalignment errors, and transceiver hardware impairments. Next, we propose random access protocols for a cell-free wireless network, ensuring successful transmission for multiple users with limited delay and energy loss, exploiting the combined effect of random atmospheric absorption, non-linearity of fading, hardware impairments, and antenna misalignment errors. We consider two schemes: a fixed transmission probability (FTP) scheme where the transmission probability (TP) of each user is updated at the beginning of the data transmission and an adaptive transmission probability (ATP) scheme where the TP is updated with each successful reception of the data. We analyze the performance of both protocols using delay, energy consumption, and outage probability with scaling laws for the transmission of a data frame consisting of a single packet from users at a predefined quality of service (QoS).

翻译：当前关于太赫兹（THz）无线通信的研究主要集中于其在亚THz频率下用于单用户回传/前传连接的应用。首先，我们建立了一个涵盖物理层损伤的THz频率信号传播广义统计模型，包括分子吸收系数服从伽马分布的随机路径损耗、由$\alpha$-$\eta$-$\kappa$-$\mu$分布表征的短期衰落、天线对准误差以及收发器硬件损伤。接下来，我们针对无蜂窝无线网络提出随机接入协议，利用随机大气吸收、非线性衰落、硬件损伤及天线对准误差的综合效应，在有限延迟和能量损耗下确保多用户成功传输。我们考虑两种方案：固定传输概率（FTP）方案——每个用户的传输概率（TP）在数据传输开始时更新；自适应传输概率（ATP）方案——TP在每次成功接收数据时更新。我们基于包含单数据包的数据帧在预定义服务质量（QoS）下的传输时延、能耗和中断概率的尺度律，对两种协议的性能进行分析。