基金资助：北京市自然科学基金项目（4222011）；
王莹，袁野，陈源彬：北京邮电大学网络与交换技术国家重点实验室
摘要：多输入多输出（MIMO）技术的不断演进展现出更大阵列孔径尺寸和更密集阵列元件排列的特性，衍生出超大规模MIMO、全息MIMO和超大规模智能超表面等技术，统称为新形态MIMO。随着通信系统从第5代向第6代移动通信系统（6G）的发展，其工作频段正在从传统的微波频段向毫米波、太赫兹等更高频段拓展，新形态MIMO的双重演进特性导致瑞利距离显著扩张，使得近场因素变得不可忽视。针对不同类型的新形态MIMO，从远场与近场信道建模、近场信道估计和波束赋形方案等方面展开综述，并介绍各种方案的技术特点。最后，探讨了新形态MIMO的未来研究方向，展示了其在增强6G移动通信系统性能方面的潜力。
关键词：新形态MIMO；信道建模；信道估计；波束赋型；
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