We consider the uplink (UL) and downlink (DL) of non-cooperative multi-cellular time-
division duplexing (TDD) systems, assuming that the number N of antennas per base station …

We propose a time division duplex (TDD) based network architecture where a macrocell tier
with a “massive” multiple-input multiple-output (MIMO) base station (BS) is overlaid with a …

Pilot contamination is known to severely limit the performance of large-scale antenna
(“massive MIMO”) systems due to degraded channel estimation. This paper proposes a …

This study addresses the pilot scheduling problem in multiuser multi‐cell massive multiple‐
input–multiple‐output (MIMO) systems, aiming at mitigating the inter‐cell interference (pilot …

The evolution of wireless communication systems is now characterised by the tremendous
growth of mobile data traffic and the number of connected devices. In response to the …

Joint Spatial Division and Multiplexing (JSDM) is a recently proposed scheme to enable
massive MIMO like gains and simplified system operations for Frequency Division Duplexing …

Channel State Information at the Transmitter (CSIT), which is crucial in multi-user systems, is
always imperfect in practice. In this paper we focus on the optimization of beamformers for …

Massive MIMO and HetNets: Benefits and Challenges Page 1 Massive MIMO and HetNets:
Benefits and Challenges Jakob Hoydis Bell Laboratories, Alcatel-Lucent, Stuttgart, Germany …

Multiple antennas facilitate the coexistence of multiple users in wireless communications,
leading to spatial multiplexing and spatial division and to significant system capacity …

This paper consider the problem of obtaining the channel state information (CSI) in downlink
massive MU-MIMO systems. As a key technology of future wireless communication, massive …