Urban Out-of-sight Propagation of millimeter waves at 30 GHz for Next generation wireless broadband services

A multi-ray model is developed for the prediction of signal strength in out-of-sight micro cellular urban streets at millimeter wave frequencies in the region 20-40 GHz. In a planned urban city, the streets have rectilinear orientation, surrounded by tall building structures with an average height of 25-30 meters. The base site antenna is kept at typical lamp-post height of about 3-5 meters, much lower than the heights of surrounding buildings. The reflected rays from the surrounding building walls are considered dominant over the diffracted rays from corners for estimating received signal strengths in out-of-sight street. The model is simulated for various sets of side-street width, main-street width, and receiver positions in out-of-sight streets. Using building and street databases, the signal coverage and interference in urban centers can be predicted with reasonable accuracy and avoids costly field measurements.