Impact of Effective Antenna Pattern on Millimeter Wave System Performance in Real Propagation Environment

Utilization of large antenna arrays in millimeter wave bands is one of the main differentiators in the forthcoming 5G deployment. However, the prevailing simulation practice for inter-site interference and co-existence studies is to use nominal antenna pattern rather than the effective pattern (reshaped by channel angular spread), leading to inaccurate link budget and interference level estimation. We visualize the impact of 3GPP UMa and UMi street canyon channel models on effective antenna array patterns and find that the downlink SINR can be overestimated by 10 to 17 dB when using nominal beam pattern rather than effective pattern.