Measurement and Modeling of Propagation Characteristics for an Indoor Environment in the 28 GHz-band

Research and development for the commercial deployment of 5G are accelerating and millimeter wave bands, which can utilize a wider bandwidth to realize larger capacity than conventional frequency bands, have become a focal point. These millimeter wave bands are different from conventional frequency bands in propagation characteristics, such as large blockage loss. Furthermore, the 5G system also assumes the case of new indoor use, such as industrial robots in factories and so forth. Therefore, a suitable propagation model for millimeter wave bands is necessary to evaluate 5G system performance by simulation or to design 5G area. In this paper, measurement campaigns of the path loss, the power delay profile and the azimuth angular profile of arrival were conducted in an indoor factory environment. In addition, we propose a suitable propagation estimation model for the indoor environment and we clarify that the proposed model is more suitable than the conventional model of the International Telecommunication Union Radiocommunication sector (ITU-R) in a subway platform by applying the measured results to a subway platform.