2022/09/25 by Zhe Wang, Jiayi Zhang, Wang, Zhe +11 · 28 citations
Engineering · #Advanced Antenna and Metasurface Technologies #Antenna Design and Analysis #FOS: Computer and information sciences #FOS: Electrical engineering #Information Theory (cs.IT) #Microwave Engineering and Waveguides #Signal Processing (eess.SP) #electronic engineering #information engineering
paper · pdf · doi:10.48550/arxiv.2209.12131
openalex publication_date 2022/09/25 · openalex created_date 2022/09/28 · openalex updated_date 2026/07/28
Extremely large-scale multiple-input-multiple-output (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.