User Coordination for Fast Beam Training in FDD Multi-User Massive MIMO

  title={User Coordination for Fast Beam Training in FDD Multi-User Massive MIMO},
  author={Flavio Maschietti and G{\'a}bor Fodor and David Gesbert and Paul de Kerret},
  journal={IEEE Transactions on Wireless Communications},
Massive multiple-input multiple-output (mMIMO) communications are one of the enabling technologies of 5G and beyond networks. While prior work indicates that mMIMO networks employing time division duplexing have a significant capacity growth potential, deploying mMIMO in frequency division duplexing (FDD) networks remains problematic. The two main difficulties in FDD networks are the scalability of the downlink reference signals and the overhead associated with the required uplink feedback for… 
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