Extremely Large Scale MIMO: Fundamentals, Challenges, Solutions, and Future Directions
Published in IEEE Wireless Communications, 2023
Recommended citation: Wang, Zhe, Jiayi Zhang, Hongyang Du, Wei EI Sha, Bo Ai, Dusit Niyato, and Mérouane Debbah. "Extremely Large-Scale MIMO: Fundamentals, Challenges, Solutions, and Future Directions." IEEE Wireless Communications, arXiv preprint arXiv:2209.12131 (2023). https://arxiv.org/abs/2209.12131
Abstract: Extremely large-scale multiple-input-multipleoutput (XL-MIMO) is a promising technology to empower the next-generation communications. However, XL-MIMO, which is still in its early stage of research, has been designed with a variety of hardware and performance analysis schemes. To illustrate the differences and similarities among these schemes, we comprehensively review existing XL-MIMO hardware designs and characteristics in this article. Then, we thoroughly discuss the research status of XL-MIMO from “channel modeling”, “performance analysis”, and “signal processing”. Several existing challenges are introduced and respective solutions are provided. We then propose two case studies for the hybrid propagation channel modeling and the effective degrees of freedom (EDoF) computations for practical scenarios. Using our proposed solutions, we perform numerical results to investigate the EDoF performance for the scenarios with unparallel XL-MIMO surfaces and multiple user equipment, respectively. Finally, we discuss several future research directions.
Index Terms: Future wireless communications, XL-MIMO, near-field communications, degree-of-freedoms.
Fig. 2 and Fig. 3: General XL-MIMO schemes and their characteristics & Fundamentals of the XL-MIMO channel modeling.