Robust Resource Allocation in Cell-Free Massive MIMO Systems

IEEE Transactions on Communications, vol. 73, pp. 5745–5759

Abstract

Cell-free networks outperform cellular networks in many aspects, yet their efficiency is affected by imperfect channel state information (CSI). In order to address this issue, this work presents a robust resource allocation framework designed for the downlink of user-centric cell-free massive multi-input multi-output (CF-mMIMO) networks. This framework employs a sequential resource allocation strategy with a robust user scheduling algorithm designed to maximize the sum-rate of the network and two robust power allocation algorithms aimed at minimizing the mean square error, which are developed to mitigate the effects of imperfect CSI. An analysis of the proposed robust resource allocation problems is developed along with a study of their computational cost. Simulation results demonstrate the effectiveness of the proposed robust resource allocation algorithms, showing a performance improvement of up to 30% compared to existing techniques.

Authors 6

1. Saeed Mashdour

   Pontifícia Universidade Católica do Rio de Janeiro

   Affiliation as printed

   Department of Electrical Engineering (DEE), Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

   Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

2. André R. Flores

   Pontifícia Universidade Católica do Rio de Janeiro

   Affiliation as printed

   Department of Electrical Engineering (DEE), Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

   Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

3. Shirin Salehi Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   Chair of Information Theory and Data Analytics, RWTH Aachen University, Aachen, Germany

4. Rodrigo C. de Lamare

   Pontifícia Universidade Católica do Rio de Janeiro

   Affiliation as printed

   Department of Electrical Engineering (DEE), Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

   Pontifical Catholic University of Rio de Janeiro, Rio de Janeiro, Brazil

5. Anke Schmeink Aachen Chair of Information Theory and Data Analytics

   RWTH Aachen University

   Affiliation as printed

   Chair of Information Theory and Data Analytics, RWTH Aachen University, Aachen, Germany

6. Paulo Ricardo Branco da Silva

   Centre for Research and Development in Telecommunications (Brazil)

   Affiliation as printed

   CPqD, Campinas, Brazil