Empirical characterization of scattering pattern of built surfaces at mm-wave frequencies

Modeling radio wave propagation at millimeter-wave frequencies in urban environments requires knowledge of the reflection and scattering properties of built surfaces. Here, a measurement campaign has been conducted in order to empirically analyze the scattering patterns of two different built surfaces, i.e., brick and glass walls. Wideband millimeter-wave channel measurement system has been used to record transfer functions of the propagation channels from 69 to 74 GHz and in the post-processing reflected and scattered multipath components have been identified from the measured averaged power delay profiles. It is found that, e.g., for the brick wall, the reflection loss at the mirror reflection angles is 1-4 dB and the losses increase almost linearly up to 45 dB as a function of the observation angle. The reflection loss is larger for the glass wall because some part of the power propagates through the glass. The results of this work can be utilized, e.g., in geometry-based stochastic channel modeling.