A simplified path loss model for investigating diffraction and specular reflection impact on millimetre wave propagation

The application of millimetre wave (mm-wave) in the Fifth Generation (5G) mobile communication systems will enrich the capacity and the data rate. However, mm-wave wireless propagation is more challenging than the microwave frequency, making the wireless channel more sensitive to blocking and shadowing effects. Understanding the diffraction impact on mm-wave wireless propagation is important for accurately specifying the rate of change in mm-wave signal strength due to attenuation losses. This paper proposes a simplified path loss model which captures the diffraction and specular reflection impacts that are affecting the mm-wave wireless propagation. The performance of 28 GHz mm-wave outdoor propagation, which is considered a key component in 5G networks, has been investigated in an actual map based scenario. Simulation results are performed to show that the traditional path loss model can present misleading results which have serious implications for the real mm-wave system applications. In addition, the results showed the characteristics of the mm-wave received signals under both the line of sight (LoS) and the nonline of sight (NLoS) conditions. The coverage trends for mm- wave frequency are also evaluated in the simulation analysis by considering the real distribution of buildings locations as blockages.