Frequency range extension of the ITU-R NLOS path loss models applicable for urban street environments with 28 GHz measurements

Since millimeter-wave (mmWave) frequency bands are strong candidates in new spectra for 5G mobiles, standardized propagation channel models are anticipated to be developed for 5G system evaluation and interference analysis. Instead of developing a new model, this paper takes the tact of examining the practicality of applying already existing, and commonly-used, ITU-R path loss models to the mmWave bands. Specifically, we focus on NLOS (non-line-of-sight) propagation in urban street canyon environments, where the radio waves propagate along the street roads and the obstruction sources are building corners. To do this, we compare measurements collected in Seoul at 28 GHz to the two ITU-R path loss models: (1) the ITU-R P.1411 Street Canyons NLOS path loss model and (2) the ITU-R M.2135 UMi (urban microcell) Manhattan-grid NLOS path loss model. The results show that the prediction of the original ITU-R models do, in fact, deviate from our 28 GHz measurement data. However, by modifying certain parameters of the ITU-R P.1411 model, we are able to generate predictions more nearly in line with the measurement data. Thusly, without modifying parameter values, the existing ITU-R P.1411 model can be still applicable to 28 GHz.