The spatial modulation principle has been widely studied in indoor optical wireless communication (OWC) systems to provide high-speed connections to users by encoding part of data in the spatial domain. To further increase the speed and to eliminate the requirements of accurate channel state information (CSI) and low channel correlation, in this Letter we propose and demonstrate an indoor OWC system with a filters-enhanced generalized spatial modulation (FE-GSM) scheme and 16-carrierless amplitude and phase (16-CAP) modulation. The 16-CAP increases the data rate in symbol domain, and the FE-GSM scheme allows activating multiple transmitters simultaneously to increase data rate in the spatial domain. Experimental results show that using a 2.5 GBaud/s indoor OWC system with three transmitters, 15 Gb/s data rate is achieved even under identical channels without pre-known CSI. The demonstrated scheme provides a promising solution to increase data rate in indoor OWC systems.

中文翻译：

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室内光学无线通信系统，具有增强了滤波器的广义空间调制和无载波幅度和相位（CAP）调制。

在室内光无线通信（OWC）系统中，已经对空间调制原理进行了广泛研究，以通过在空间域中对部分数据进行编码来为用户提供高速连接。为了进一步提高速度并消除对精确信道状态信息（CSI）和低信道相关性的要求，在本信中，我们提出并演示了一种室内OWC系统，该系统具有滤波器增强的广义空间调制（FE-GSM）方案和16 -无载波幅度和相位（16-CAP）调制。16-CAP增加了符号域中的数据速率，而FE-GSM方案允许同时激活多个发射机以提高空间域中的数据速率。实验结果表明，使用具有三个发射器的2.5 GBaud / s室内OWC系统，即使在没有已知CSI的相同信道下，也可以达到15 Gb / s的数据速率。演示的方案为提高室内OWC系统中的数据速率提供了有希望的解决方案。