In this paper, we address a multiple-input multiple-output (MIMO) communication system based on generalized spatial modulation (GSM) and dual-polarized (DP) antennas in sub-TeraHertz (sub-THz) bands to improve the Spectral Efficiency (SE) while reducing the spatial correlation effect and the space occupancy. Moreover, the joint Maximum Likelihood (ML) detector and a Modified Ordered Block Minimum Mean-Squared Error (MOB-MMSE) detector algorithm are proposed to detect jointly the complex symbols and the virtual bits conveyed by the activated polarization and the transmit antenna combination index. MOB-MMSE can achieve near-ML performance with low complexity. The performance of DP-GSM system over correlated Rayleigh/Rician fading and indoor sub-THz channels is studied. Provided results show that DP-GSM system is robust to the spatial correlation effects under Rician fading channel. In addition, an average bit-error probability (ABEP) upper bounding is derived and analyzed for the DP-GSM system over correlated Rayleigh/Rician fading channels. Since the sub-THz band suffers from many technological limitations and severe RF-impairments such as low transmit output power and important phase noise (PN), the DP-GSM system is studied by considering the sub-THz impairments. Moreover, the Dual Polarized Spatial Multiplexing (DP-SMX) and the Uni-Polarized GSM (UP-GSM) are compared with the DP-GSM system. The results reveal that DP-GSM with low order modulation schemes as QPSK outperforms the UP-GSM. Besides, DP-GSM and DP-SMX provide a good performance up to medium PN, which is interesting for sub-THz bands, but DP-GSM can reduce the transceiver cost by using a lower number of RF chains when the used transmitter architecture is based on RF-switching.

中文翻译：

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使用具有射频损伤的双极化广义空间调制的亚太赫兹无线系统


在本文中，我们提出了一种基于广义空间调制（GSM）和亚太赫兹（sub-THz）频段双极化（DP）天线的多输入多输出（MIMO）通信系统，以提高频谱效率（ SE）同时减少空间相关效应和空间占用。此外，提出了联合最大似然（ML）检测器和修改有序块最小均方误差（MOB-MMSE）检测器算法来联合检测由激活极化和发射天线组合索引传达的复杂符号和虚拟比特。 MOB-MMSE 可以以较低的复杂度实现接近 ML 的性能。研究了 DP-GSM 系统在相关瑞利/莱斯衰落和室内亚太赫兹信道上的性能。结果表明，DP-GSM系统对莱斯衰落信道下的空间相关效应具有鲁棒性。此外，还导出并分析了相关瑞利/莱斯衰落信道上的 DP-GSM 系统的平均误码概率 (ABEP) 上限。由于次太赫兹频段受到许多技术限制和严重的射频损伤，例如低发射输出功率和重要的相位噪声（PN），因此通过考虑次太赫兹损伤来研究DP-GSM系统。此外，还将双极化空间复用(DP-SMX)和单极化GSM(UP-GSM)与DP-GSM系统进行了比较。结果表明，采用 QPSK 等低阶调制方案的 DP-GSM 优于 UP-GSM。此外，DP-GSM 和 DP-SMX 提供高达中等 PN 的良好性能，这对于亚太赫兹频段很有趣，但当使用的发射器架构为基于射频开关。