Directional Characteristics of Millimeter Wave Propagation Channel in Outdoor Urban Picocell

摘要

One of the ways to meet the growing demand for higher data rates is to exploit the large amount of spectral resources available in the millimeter wave frequency band. The unlicensed 60 GHz band with continuous bandwidths of more than 7 GHz is a very attractive candidate for use in the future heterogeneous cellular networks. Large free space path loss and atmospheric attenuation in 60 GHz propagation channel necessitates the use of high gain directional antennas or antenna arrays. The channel characteristics such as the directional properties in different environment is therefore very important for use of techniques like beamforming and beamsteering. We developed a low cost double directional millimeter wave channel sounding system capable of carrying out measurement in outdoor environments. By analyzing the data from our measurement campaign in outdoor urban pico-cell environment we show the existence of paths other than the direct path in both line of sight (LOS) and obstructed LOS cases. Some of the prominent clusters and their properties are also examined.