Path loss characteristics in the OOS regions of urban microcellular environments

With the rapid development of mobile radio communications, frequency reuse is of importance to make efficient use of the limited frequency spectrum. The microcellular concept is helpful in this respect. Using low base station antennas and low transmitting powers, microcells can also provide inexpensive infrastructure and small size subscriber units. Path loss is essential in the determination of the coverage area of microcells. Considerable research has been devoted to the development of propagation prediction models of microcells and several prediction models based on ray tracing and methods of uniform theory of diffraction (UTD) have been reported. Calculations have been carried out and compared with the measured results to verify the validity of these models. Using the ray tracing technique the authors calculate the path loss in the out-of-sight (OOS) regions for a variety of urban environments. Firstly, the effect of the neighboring streets on the path loss of the OOS regions is examined. Secondly, the path loss along the streets which intersects the main street non-perpendicularly is calculated.