Performance analysis of mmWave radio propagations in an indoor environment for 5G networks

Existing wireless communications in the sub-6 GHz bands are facing challenges from the growing demand for higher data rates and better quality of services. To satisfy these demands, the fifth generation (5G) mobile network would consider unused spectrum in the millimeter wave (mmWave) spectrum (30-300 GHz). The shortage of bandwidth in the sub-6 GHz band is solved using mmWave technology. Furthermore, mmWave provides significantly higher throughput, data rate, and capacity. Despite the fact that a huge bandwidth is employed, mmWave technology suffers from diffuse scattering from rough materials, path loss, reflection loss, atmospheric attenuation, building penetration loss, and shadowing which leads to a decrease in the transmitted signal power. Therefore, a reliable and accurate channel model is important in the mmWave bands, particularly for the indoor environment. Moreover, by using technologies like beam-forming and others coupled with mmWave, the listed impairments are minimized. In this work, we analyze the performance of different path loss models (CI, free space, and two rays) at 38, 60, and 73 GHz carrier frequencies in terms of path loss in terms of separation distance between transmitter and receiver. Additionally, we have evaluated the performance of the path loss with respect to the break point distance to enhance the received signal power and throughput. We have also done analysis of the directional power delay profile with received signal power, path loss and path loss exponent (PLE) at 38 GHz and 73 GHz mmWave bands for both LOS and NLOS by using uniform linear array (ULA) 2 x 2 and 64 x 16 antenna configurations using the channel model simulator (NYUSIM). The simulation results show the performance of different path loss models in the mmWave and sub 6 GHz bands. Path loss in the close-in (CI) model at mmWave bands is larger than that of free space and two ray path loss models, because it considers all shadowing and reflection effects between transmitter and receiver.