Massive multiple-input-multiple-output (MIMO) has been considered as one of the promising technologies for the future communications due to its high spectrum efficiency. In massive MIMO systems, hybrid precoding is widely adopted for it can reduce the unacceptable power consumption with a small number of radio- frequency (RF) chains. However, one RF chain can serve at most one user. Consequently, the number of simultaneously served users are strictly limited. To break this limitation, the idea of beamforming MIMO non-orthogonal multiple access (NOMA) has been proposed. In beamforming MIMO NOMA systems, one RF chain can support two or more users, where users with the same beam selection are paired into one cluster and served by an identical RF chain. However, the traditional beams are so narrow that only a few users can find a match while most of the users still remain single and perform orthogonal multiple access. To solve the problem, we propose a new scheme called multi-resolution beamforming and user clustering scheme. We first utilize beams with narrow angle range and higher array gain for user clustering. Those users which cannot be paired with these beams are clustered by a new beam codebook whose beams have a wider angle range. The selected wide beams are well-designed to avoid bringing interference to the previously paired users. The proposed scheme raises the possibility for users being paired into clusters while keeping a satisfying array gain. Therefore, more users in the cell can take advantages of NOMA to achieve a higher spectral efficiency. The simulation results demonstrate that the proposed scheme outperforms existing schemes under different scenarios.


    Zugriff

    Zugriff prüfen

    Verfügbarkeit in meiner Bibliothek prüfen

    Bestellung bei Subito €


    Exportieren, teilen und zitieren



    Titel :

    Multi-Resolution Beamforming and User Clustering in Downlink Massive MIMO Non-Orthogonal Multiple Access System


    Beteiligte:
    Zhang, Xinyi (Autor:in) / Wang, Jun (Autor:in) / Wang, Jintao (Autor:in) / Tan, Jingbo (Autor:in)


    Erscheinungsdatum :

    01.04.2019


    Format / Umfang :

    322193 byte





    Medientyp :

    Aufsatz (Konferenz)


    Format :

    Elektronische Ressource


    Sprache :

    Englisch



    Hybrid Beamforming for Downlink Massive MIMO Systems with Multiantenna User Equipment

    Payami, Sohail / Ghoraishi, Mir / Dianati, Mehrdad | IEEE | 2017


    Robust Non-Coherent Beamforming for FDD Downlink Massive MIMO

    Rottenberg, Francois / Lee, Ming-Chun / Choi, Thomas et al. | IEEE | 2020


    Clustering Method in Downlink Cell-Free MIMO Using Layered Partially Non-orthogonal ZF-Based Beamforming

    Ishii, Daisuke / Hara, Takanori / Nonaka, Nobuhide et al. | IEEE | 2023



    On Short Term Fairness and Throughput of User Clustering for Downlink Non-Orthogonal Multiple Access System

    Al-Wani, Mohanad M. / Sali, A. / Ali, Borhanuddin M. et al. | IEEE | 2019