5G Multi-User System Simulations in Line-of-Sight With Space-Tapered Cellular Base Station Phased Arrays

The performance of space-tapered multi-beam arrays with minimized side lobe levels is statistically evaluated in a line-of-sight propagation environment within a cell sector in terms of the signal-to-interference-plus-noise ratio at the multiple user ends. Comparative analyses are performed to examine the advantages of space-tapered, irregular arrays over the conventional regular array layouts. The system model is formulated with a meaningful link-budget analysis. Two different precoding techniques, conjugate beamforming and zero-forcing, are applied to compute the excitation coefficients at the antenna elements. The effects of several practical factors such as approaches in user scheduling, errors in channel state information estimation and quantization in excitation amplitudes and phases are studied. The simulation results indicate that space-tapered arrays with conjugate beamforming statistically perform better than the regular counterparts and can achieve similar performance to zero-forcing precoding when the impact of non-ideal system conditions is considered.