Measurements at 28 GHz for 90% Outdoor Coverage from Macro rooftop Sites in Urban Street Canyon

Path gain and effective directional gain in urban canyons from actual building roof tops are characterized based on a massive data set of 3000 links on 13 streets in two cities, with over 21 million individual measurements. Large streetstreet path gain variation is found, with median street path gain varying over 35 dB for the same range of distances. Down the canyon links in nominal "LOS" are found to suffer an average excess loss of 11 dB relative to free space at 200 m. Empirical slope-intercept fit model represents the nominal "LOS" data with 7.3 dB standard deviation. Offsetting the base antenna 5 m away from roof edge, as is common in macro cellular deployments, introduces an additional average loss of 15 dB average loss at 100 m. Around the corner loss is well modeled by a diffraction formula with an empirically obtained diffraction coefficient. Effective azimuthal gain degradation due to scatter is limited to 2 dB for 90% of data, supporting effective use of high gain antennas in urban street canyons. Temporal dynamics for stationary links were modest, with under 2 dB penalty for failing to update beam aim more often than every 10 sec.