Path loss model in indoor environment at 40 GHz for 5G wireless network

The unused millimeter-wave (mm-wave) spectrum offers a superb opportunity to increase mobile broadband capacity, this is due to the enormous amount of available raw bandwidth. The need for studying the millimeter band frequency becomes a critical issue nowadays to adequate with 5G requirement. This paper presents the outcome of indoor measurement campaigns for cellular systems at 40 GHz for line of sight (LOS) and non-line of sight (NLOS) scenarios. To effectively evaluate the performance of 5G wireless systems in this band, the path loss (PL) models are investigated for this environment. In this paper, single frequency path loss models are presented using the close-in free space reference distance (CI) model and the floating intercept (FI) model. Moreover, the two-ray model is investigated for this band using the same measurement parameters and it is compared with the measurement data. The results find that the path loss exponent (PLE) for CI model and slop line for FI model are identical for LOS and NLOS scenarios. The PLE is 1.8 for LOS scenario and 2.9 for NLOS scenario. The results show that both CI and FI models are most suitable for indoor large-scale path loss modeling for 5G system at 40 GHz in such environment.