Impact of Spatial Consistency on Dynamic Beamforming for Millimeter-Wave Cellular Systems

Research output: Contribution to conferencePaper, not in proceeding

Abstract

Millimeter-wave (mmWave) frequencies are set to play an important role in fifth-generation (5G) wireless systems. A pre-requisite for the design and performance assessment of 5G wireless is the understanding of the involved propagation processes and derivation of insightful channel models. Unlike bands below 6 GHz, several additional modelling features need to be catered for at mmWaves. For dynamic scenarios, spatial consistency (SC) is a novel mandatory feature of 5G channel models ensuring continuity in the channel parameters as the user equipment (UE) moves along a trajectory. Such mobility has an enormous impact on the performance of common beamforming techniques leveraged to deliver high spectral efficiencies. Unlike others, this paper aims to quantify the impact of SC on dynamic mmWave beamforming performance. We focus on the downlink of a 28 GHz urban microcellular scenario, where the base station comprises of a 16x16 cross-polarized uniform planar array (UPA) serving multiple 4x4 UPA UEs. Using the standardized Third Generation Partnership Project 38.901 SC-I procedure, we evaluate the signal-to-interference-plus-noise ratio of a UE and the system ergodic sum spectral efficiency with zero-forcing, block diagonalization, and signal-to-leakage-plus-noise ratio beamforming. With each technique, our results show that at practical signal-to-noise-ratio levels, spatially consistent channels yield a significant performance loss relative to the case without SC due to substantial spatial correlation across the channel parameters. We demonstrate the validity of this conclusion with multiple UE trajectories. The results serve as a guideline to recalibrate our expectations from dynamic beamforming.

Details

Authors
Organisations
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Other Electrical Engineering, Electronic Engineering, Information Engineering

Keywords

  • Millimeter-wave systems, Dynamic propagation channels, Baseband beamforming control, Spatial consistency, 3GPP compliance
Original languageEnglish
Number of pages9
Publication statusAccepted/In press - 2019 Jan 8
Publication categoryResearch
Peer-reviewedNo
Event9th MC and Technical Meeting of COST IRACON : Action CA15104 - Dublin City University, All Hallows Campus, Dublin, Ireland
Duration: 2019 Jan 162019 Jan 18
http://www.iracon.org/meeting/9th-mc-meeting-and-9th-technical-meeting/

Conference

Conference9th MC and Technical Meeting of COST IRACON
CountryIreland
CityDublin
Period2019/01/162019/01/18
Internet address

Bibliographic note

COST IRACON Action: CA15104