Holographic multiple-input multiple-output (HMIMO) systems constitute a promising technology in support of next-generation wireless communications, thus paving the way for a smart programmable radio environment. However, despite their significant potentials, further fundamental issues remain to be addressed, such as the acquisition of accurate channel information. Indeed, the conventional angular-domain channel representation is no longer adequate for characterizing the sparsity inherent in HMIMO channels.

中文翻译：

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全息多输入、多输出系统：信道估计和性能


全息多输入多输出（HMIMO）系统是支持下一代无线通信的一项有前途的技术，从而为智能可编程无线电环境铺平了道路。然而，尽管它们潜力巨大，但进一步的基本问题仍有待解决，例如获取准确的渠道信息。事实上，传统的角域信道表示不再足以表征 HMIMO 信道固有的稀疏性。