July 7, 14, and 28 and August 11, 2016 • Hosted by the Institute for Telecommunication Sciences
Objective: Develop draft best practices for propagation measurements to assess the impact of losses caused by clutter on estimates of aggregate interference to incumbent systems in the 3.5 GHz band.
As the FCC proceeds with rulemaking to open the 3.5 GHz band to sharing, a number of organizations have begun executing propagation loss measurements in the band. One important goal of these measurements is to assess the impact of clutter (man-made structures and foliage) on estimates of pathloss for use in aggregate interference models. This is a new research question and no standardized best practices exist for this type of measurement.
The objective of these initial virtual meetings was to bring together researchers from government, academia, and industry to discuss key requirements for measurement system design and validation. ITS hosted a series of four Webinars which included a kick-off meeting, a system architecture meeting, a propagation modelling meeting, and an uncertainty/current best practices meeting. The webinars were hosted by WInnForum.
July 7, 2016, 1:00 p.m. to 2:00 p.m. MST
We discussed the motivation behind this workshop series and provided a brief overview of the 3.5 GHz measurements that ITS conducted in Denver, CO and San Diego, CA. This presentation provided a high level overview of our measurement methods, data post-processing, and subsequent data analysis. To promote future collaboration, meeting participants performing measurements in this band were asked to provide a brief overview of the types and locations of measurements they have accomplished and have planned. [slide deck]
July 14, 2016, 1:00 p.m. to 2:00 p.m. MST
ITS 3.5 GHz Propagation Measurement System
Dr. Robert Johnk of NTIA/ITS provided an overview of the continuous wave (CW) measurement system ITS developed to measure both propagation and clutter losses. The presentation covered system architecture, verification bench tests, and selected system validation tests. Finally, sample results from a recent measurement campaign were presented. [slide deck]
July 28, 2016, 1:00 p.m. to 2:00 p.m. MST
Use of the Irregular Terrain Model (ITM) and Other Propagation Models
Paul McKenna of NTIA/ITS provided an overview of key propagation models used for system compatibility analysis in the 3.5 GHz band. This included a description of ITS’s Irregular Terrain Model (ITM), discussion of valid implementations of the software which are of use to researchers, typical model settings, the ranges of model applicability, and its limitations. Mr. McKenna also discussed ITU-R P.452, Prediction procedure for the evaluation of interference between stations on the surface of the Earth at frequencies above about 0.1 GHz, and the Extended-Hata model which was developed by NTIA for use in the 3.5 GHz rulemaking analysis. [slide deck]
August 11, 2016, 1:00 p.m. to 2:00 p.m. MST
Uncertainties/Current Best Measurement Practices
This session provided an overview of sources of uncertainty and good measurement practices. Speakers from either NIST and ITS presented information on some of their current research into uncertainty analysis, terrain database variations, and other timely research topics. [slide deck]
For more information email the Workshop Chair: Chriss Hammerschmidt, email@example.com, 303-497-5958