Hybrid beamforming in uplink massive MIMO systems in the presence of blockers
Paper in proceedings, 2017

Hybrid beamforming (HBF) is a potential solution to reduce the baseband hardware cost in massive multiple-input multiple-output (MIMO) systems that has drawn considerable attention recently. In this paper, we consider the uplink of a multiuser massive MIMO system in the presence of blockers. Such blockers, which arise from, for example, users served by other non-cooperative base stations (BSs), can limit the system performance if not handled properly. We propose a HBF scheme that can remove the impact of blockers, while preserving signals from intended users. Specifically, in our two-step receive beamforming scheme, the analog beamformer (ABF) is designed based on channel covariance matrices to minimize the powers of blockers, while the digital beamformer (DBF) deals with inter-user interference. We propose an iterative algorithm that efficiently gives a good sub-optimal solution to the NP-hard problem in the ABF design. Moreover, we consider a more complete BS architecture by incorporating automatic gain control (AGC) and analog-to-digital converter (ADC). As we show in the simulations, for a system with full-precision ADCs, our scheme approaches the sum rate of an ideal fully-digital system. Interestingly, for a system with low-resolution ADCs, our HBF scheme can even outperform a fully-digital system.

Author

Xinlin Zhang

Chalmers, Signals and Systems, Signalbehandling och medicinsk teknik, Signal Processing

Mikael Coldrey

Ericsson AB

Chalmers, Signals and Systems, Signalbehandling och medicinsk teknik, Signal Processing

Thomas Eriksson

Chalmers, Signals and Systems, Communication and Antenna Systems, Communication Systems

Mats Viberg

Chalmers, Signals and Systems, Signalbehandling och medicinsk teknik, Signal Processing

ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings

15206149 (ISSN)

6503-6507 7953409

Areas of Advance

Information and Communication Technology

Subject Categories

Signal Processing

DOI

10.1109/ICASSP.2017.7953409

More information

Latest update

6/25/2018