Signal quality, network densification, and throughput performance in 5G heterogeneous networks: A quantitative investigation of key performance indicators in urban sub-6 GHz deployments

¹ Department of Electrical and Electronics Engineering, Accra Technical University, Accra, Ghana
² Department of Theoretical and Applied Biology, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
³ Department of Data Science and Analytics, Thrive Africa, Accra, Ghana

Abstract

The worldwide deployment of 5G mobile networks has increased research interest in how different network designs maintain service quality as the number of user devices grows significantly. The paper investigates how different 5G HetNet deployment patterns in urban sub-6 GHz networks relate signal quality, measured by the signal-to-interference-plus-noise ratio, to network densification variables that affect throughput performance. The paper uses Pearson’s correlation analysis and multiple linear regression to create a predictive hierarchy of KPIs based on field measurement, from 312 geospatially distributed sample points across four deployment tiers, including macro-only, two-tier pico-macro, three-tier femto-pico-macro and millimetre-wave dense small cell. The findings demonstrate that SINR serves as the most accurate throughput predictor (β = 0.612, p < 0.001), while UE density (β = −0.271), followed by handover frequency (β = −0.189), also contribute significantly to the predictive model. Dense three-tier HetNet configurations reduce throughput degradation from 58.8% to 25.0% under high-density load conditions, and mmWave small cell deployments demonstrate the lowest degradation ceiling at 19.0%. The paper presents empirical evidence that strategic small-cell densification, together with interference management, is necessary to maintain 5G network performance in a high-density urban environment. Practical recommendations are offered for network planners and policymakers in resource-constrained deployment contexts.