Adaptive Hybrid Precoding Strategy for Cell-Free Massive MIMO

• Published in: Journal of Microwaves, Optoelectronics and Electromagnetic Applications Vol. 22; no. 2; pp. 257 - 267
• Main Authors: Mathe, Dercio M., Acatauassu, Diogo, Borges, Gilvan S., Rodrigues, Roberto M., Cavalcante, André M., Marquezini, Maria V., Almeida, Igor, Costa, João C. W. A.
• Format: Journal Article
• Language: English
• Published: Sociedade Brasileira de Microondas e Optoeletrônica e Sociedade Brasileira de Eletromagnetismo 01.06.2023; Sociedade Brasileira de Microondas e Optoeletrônica; Sociedade Brasileira de Eletromagnetismo
• Subjects: Cell-free (CF) massive multiple-input multiple-output (MIMO); ENGINEERING, ELECTRICAL & ELECTRONIC; hybrid precoding; maximum ratio transmission (MRT); minimum mean-square error (MMSE); OPTICS; spectral efficiency (SE); Cell-free (CF) massive multiple-input multiple-output (MIMO); maximum ratio transmission (MRT); minimum mean-square error (MMSE); hybrid precoding; spectral efficiency (SE)
• ISSN: 2179-1074; 2179-1074
• DOI: 10.1590/2179-10742023v22i2266934

Abstract This work presents an adaptive hybrid signal precoding strategy for Cell-Free (CF) Massive multiple-input multiple-output (MIMO) systems. The proposed solution exploits the advantages of both distributed and centralized signal processing schemes to perform precoding. In our proposal, some access points (APs) are dynamically configured to be used in a centralized precoding scheme, whereas others are adjusted to employ a distributed method. Simulation results show that it is possible to achieve a good compromise between spectral efficiency (SE) and computational complexity (CC) in CF Massive MIMO systems finding a sensible balance between APs utilized in centralized and distributed precoding. To the best of our knowledge, prior-art solutions have not addressed an adaptive hybrid precoding method itself, they have only proposed a specific solution for each architecture, i.e., distributed or centralized.