Attenuation Measurements and Propagation Modeling in the W-Band

The frequency range that extends from 70 to 115 GHz presents low gaseous attenuation and offers the possibility of implementing radio links with capabilities of transporting more than 1 Gb/s over distances up to a few kilometers. A better knowledge of the propagation characteristics of the atmosphere at these frequencies can benefit future technological advances, providing better performance in terms of the use of radio resources. Unfortunately, the number of propagation results communicated for this band is very small. In this paper, propagation in this frequency range is analyzed on the basis of two-year experimental measurements carried out in Madrid, Spain, on a commercial link working at 75 and 85 GHz. Rain attenuation is the most relevant propagation effect in the W-band. Attenuation measurements are processed to remove wet antenna effects, leaving only the path attenuation time series. Statistics obtained from these time series are compared with a number of model predictions that use rain information of various types as input data, assessing in this way their precision and usefulness.