Millimeter-wave channel model parameters for urban microcellular environment based on 28 and 38 GHz measurements

Abstract

To meet the increasing demand for 5G high datarate communications, millimeter-wave frequency bands are expected to be utilized. However, the existing channel models are not applicable to predict channel behaviors in these frequency bands. In this paper we investigate millimeter-wave channel model parameters including path loss exponents, delay and angular spread, and clustering parameters based on measurements collected in urban microcell environments at 28 and 38 GHz. Our measurement data were obtained with a wideband millimeter-wave channel sounder equipped not only an omnidirectional antenna and but also a steerable direction antenna. The measurement campaigns were held in Dunsan District area in Daejeon City, Korea, which is a typical downtown area surrounded with high-rise buildings. From our analysis, fitting results indicate that a path loss exponent of LoS is close to the free space path loss exponent of 2. In NLoS, the path loss exponent is about 3 at both frequencies. Furthermore, we observe that delay and angular spread, and clustering parameters at 28 GHz are similar to those at 38 GHz. We believe that these analysis results will facilitate developing millimeter-wave band 5G wireless systems.