DESIGN AND IMPLEMENTATION OF A 72 & 84 GHZ TERRESTRIAL PROPAGATION EXPERIMENT; EXPLOITATION OF NEXRAD DATA TO STATISTICALLY ESTIMATE RAIN ATTENUATION AT 72 GHZ

The wireless communication sector is rapidly approaching network capacities as a direct result of increasing mobile broadband data demands. In response, the Federal Communications Commission allocated 71-76 GHz “V-band” and 81-86 GHz “W-band” for terrestrial and satellite broadcasting services. Movement by the telecommunication industry towards W/V-band operations is encumbered by a lack of validated and verified propagation models, specifically models to predict attenuation due to rain. Additionally, there is insufficient data available at W/V-bands to develop or test propagation models. The first aim of this study was the successful installation and operation of a terrestrial link to collect propagation data at W/V-band frequencies. In September 2015, the University of New Mexico, in collaboration with the Air Force Research Laboratory’s Space Vehicle Directorate, NASA’s Glenn Research Center and industry partners including (ACME, Applied Technology Associates, and Quinstar Technologies, Inc.) established the W/V-band Terrestrial Link Experiment (WTLE). WTLE was installed in the Albuquerque metro area with persistent tonal transmissions at 72 GHz and 84 GHz on a 23.5 km slanted path. The second aim of this study was the utilization of the National Weather Service’s Next Generation Weather Radar (NEXRAD) system data to statistically estimate attenuation due to rain at 72 GHz. NEXRAD data provides a distributed sense of rain rates along WTLE’s path and alleviates challenges associated with instrumenting the 23.5 km link. Furthermore, NEXRAD data alleviates the need to develop complicated routines using in-situ meteorological measurements to estimate the size of the rain cell affecting the link. Non-linear regression techniques were applied on 2017 monsoon season data to obtain rain rate power law model coefficients. Testing of these coefficients was conducted on 2018 monsoon season data with satisfactory results. The techniques employed in this analysis represent a significant advancement in the ability to predict attenuation due to rain at 72 GHz for terrestrial links by enabling the use of historical archives of publicly available National Weather Service NEXRAD data. The technique has promising potential for estimation of path attenuation due to rain for links other than WTLE because of the vast nationwide coverage provided by NEXRAD systems