Radio Propagation Measurements and Statistical Channel Models for Outdoor Urban Microcells in Open Squares and Streets at 142, 73, and 28 GHz

A comprehensive understanding of outdoor urban radio propagation at mmWave and sub-THz frequencies is crucial for enabling novel applications such as wireless cognition, precise position-location, and sensing. This article summarizes extensive measurements and statistical analysis of outdoor radio propagation data collected in New York City between 2012 and 2021 to formulate a multiband empirical 3-D statistical channel model (SCM) for outdoor urban open squares and streets. Path loss (PL) models and SCMs are derived from over 21 000 power delay profiles (PDPs) measured in Brooklyn and Manhattan. Analysis of multipath components (MPCs) in PDPs reveals underlying statistical distributions for wireless channel parameters, including time-clusters (TCs), subpaths (SP) in TCs, delays and powers of TCs and SP, and spatial-cluster directions. Observations at 142 GHz suggest a sparse channel as SP in TCs are exponentially distributed with narrower spread spatial-clusters and higher Ricean K-factor, unlike the uniform distributions and lower K-factors at 28 and 73 GHz. The proposed SCMs at 142, 73, and 28 GHz extend the open-source NYUSIM channel simulator into sub-THz bands up to 150 GHz. The SCMs aid in designing modems, antenna arrays, beamforming, and spatial multiplexing approaches, while providing an empirical baseline for propagation simulation and prediction tools such as ray tracers.