User Association and Hybrid Beamforming Designs for Cooperative mmWave MIMO Systems

Abstract

Hybrid analog and digital beamforming has emerged as a key enabling technology for millimeter wave (mmWave) massive multiple-input multiple-output (MIMO) communication systems since it can balance the trade-off between system performance and hardware efficiency. Owing to the strong ability of central control, cooperative networks show great potential to enhance the spectral efficiency of mmWave communications. In this paper, we consider cooperative mmWave MIMO systems and propose user association and hybrid beamforming design algorithms for three typical hybrid beamforming architectures. The central processing unit (CPU) of the cooperative networks first matches the service pairs of base stations (BSs) and users. Then, an iterative hybrid beamforming design algorithm is proposed to maximize the weighted achievable sum-rate performance of the mmWave MIMO system with fully connected hybrid beamforming architecture. Moreover, a heuristic analog beamforming design algorithm is introduced for the fixed subarray hybrid beamforming architecture. In an effort to further exploit multiple-antenna diversities, we also consider the dynamic subarray architecture and propose a novel antenna design algorithm for the analog beamforming design. Simulation results illustrate that the proposed hybrid beamforming algorithms achieve a significant performance improvement than other existing approaches and the dynamic subarray architecture has great advantages of improving the energy efficiency (EE) performance.

RIS-Assisted Hybrid Beamforming and Connected User Vehicle Localization for Millimeter Wave MIMO Systems

“…The use of fully digital beamforming has been widely adopted in traditional communication systems, but it requires a radio frequency (RF) chain per antenna element, which increases power consumption, hardware complexity, and costs. As a solution to this problem, hybrid beamforming has been proposed as an alternative approach for mmWave massive multiple-input and multiple-output (MIMO) systems [ 17 , 18 ]. To further develop traditional hybrid beamforming, the proposed conjugate gradient-based hybrid beamforming algorithm can deal with the user sub-rate maximization problem and offer the benefit of significantly improving spectral efficiency.…”

“…There are three hybrid beamforming architectures investigated in the literature: fully connected, fixed subarray and dynamic subarray. In [ 17 ], an iterative hybrid beamforming design algorithm was proposed with a fully connected architecture to maximize the weighted sum-rate performance of mmWave MIMO systems. The authors considered an RIS-aided mmWave-NOMA downlink system with a hybrid beamforming structure in [ 18 ].…”

Frequency divided group beamforming with sparse space‐frequency code for above 6 GHz URLLC systems

“…Recent research and practice have focused on a technique known as hybrid beamforming, which uses large antenna arrays at both the transmitter and receiver along with baseband precoding and combining techniques [9][10][11][12][13][14][15][16]. The suggested method deviates from earlier works in that a hybrid beamforming technique is used.…”