In Pursuit of Consensus on Clutter

ISART 2024 sought consensus on how to address the pressing challenge of developing, agreeing on, and applying radio frequency propagation models that take into account the impact of foliage and buildings—clutter—for planning of both spectrum policy and spectrum-dependent systems of all kinds. The development of such models has historically been fraught with competing methodologies, assumptions, and toolsets. Yet today’s environment of ubiquitous spectrum sharing, increasing system diversity and complexity, and rapidly expanding exploitation of mid-band frequencies means that the demand for more modeling fidelity and greater modeling accuracy is both urgent and compelling. ISART 2024 focused on how the broader community of researchers and system owners can collectively marshal and invest its finite resources to develop, validate, and apply new, more broadly used clutter models. These tools are needed to ensure that the ambitious goals set forth in both the U.S. National Spectrum Strategy (NSS) and the 2023 World Radio Conference (WRC-23) can be achieved.

Click on a speaker's name to access their presentation where available. Speaker biographies are here.

Monday, June 10, 2024 (Afternoon)

• Tutorial: Building and Evaluating a Statistical Propagation Model
  The purpose of this tutorial was to guide attendees to build their own statistical propagation model based on clutter metrics derived from lidar data. Attendees were able to build, experiment, and evaluate their propagation models against real clutter measurement datasets. Each attendee was provided with a cloud-based Python programming environment accessible through the web browsers on their laptops (no software installation necessary). Example code and step-by-step instructions guided attendees to (a) measure clutter statistics from LiDAR data, (b) formulate a clutter loss model, and (c) assess their model’s generalizability against measurements in new clutter environments. No programming experience was necessary, but tutorial attendees had to have a computer with a browser and a GitHub account. [Click here for introductory slides]
  • William Kozma, Jr., NTIA Institute for Telecommunication Sciences and Head of U.S. Delegation to ITU-R Study Group 3
  • Max Hollingsworth, University of Colorado Boulder and NTIA Institute for Telecommunication Sciences
  • Anthony Romaniello, NTIA Institute for Telecommunication Sciences

Tuesday, June 11, 2024

• Introduction and Opening Remarks
  Jeremy Glenn, NTIA Institute for Telecommunication Sciences
• Keynote Address
  Shiva Goel, NTIA Senior Spectrum Advisor
  
• Fireside Chat: Clutter is a Universal Concern
  • Charles Cooper, NTIA Associate Administrator and Director Office of Spectrum Management (Moderator)
  • Clare Allen, Ofcom Senior Spectrum Engineer and ITU-R Study Group 3 Chair
  • Stephane Gagnon, Vice-president of Research at the Communications Research Centre, Innovation, Science and Economic Development Canada
• Technical Talk: Clutter Modeling: Today’s Shortfalls and Tomorrow’s Opportunities
  William Kozma, Jr., ITS Telecommunications Theory Division and Head of U.S. Delegation to ITU-R Study Group 3
• Technical Talk: Radar Clutter [Virtual]
  Dr. William Melvin, Deputy Director for Research, Georgia Tech Research Institute (GTRI)
• Panel: Model Use Cases and Requirements
  Propagation models are used for a wide variety of purposes, from predicting communications link performance, to broadcast coverage, to interference analyses, and more. Each use case drives different propagation model requirements, and the use cases span diverse geometries, including airborne-terrestrial, terrestrial-terrestrial, satellite-terrestrial, etc. Given this broad scope, this panel described selected use cases of current and future interest, and discussed propagation model requirements (specifically including clutter) derived from their applications. Panelists/speakers addressed: What are the different use cases for propagation/clutter models? What is known about the problem? What is needed from the output of the model? What propagation metrics need to be predicted? What role does clutter play in the analysis?
  • Kalle Kontson, Johns Hopkins University Applied Physics Laboratory (Moderator)
  • Andrew Clegg, Spectrum Engineering Lead, Google
  • Prasanna Satarasinghe, Army Spectrum Management Office (ASMO), U.S. Department of Defense, Chief Information Officer
  • Neeti Tandon, Distinguished Member of Technical Staff & Technical Fellow, AT&T
  • Christopher Anderson, NTIA, Institute for Telecommunication Sciences
• Panel 2 – Modeling
  The final output of the development of a clutter model is shaped by the multiple decisions that go into it. Some decisions are straightforward, some are more nuanced, and all are influenced by the scenario the modeling is targeted to support. In all cases, documentation about these decisions is often absent from the final publication of the clutter model itself. The result is models with implicit assumptions that can affect everything from their range of applicability to the underlying uncertainty within the model. This panel discussed how to formalize the model development process for greater transparency and usability, from decision-making steps through model evaluation. All models require some simplifying assumptions: how do we identify and capture the impact of those simplifications? What constitutes sufficient documentation of a model? How can we reduce barriers to improving and expanding existing models? How can we objectively evaluate model performance?
• William "Billy" Kozma, Jr., ITS Telecommunications Theory Division and Head of U.S. Delegation to ITU-R Study Group 3 (Moderator)
• Tingjun Chen (Duke), Assistant Professor, Electrical and Computer Engineering and Computer Science, Duke University.
• Ted Kaplan, Chief Operating Officer and Chief Systems Engineer, RFK Engineering
• Roy Sun, Principal Architect, CableLabs

Wednesday, June 12, 2024

• Opening Remarks
  William "Billy" Kozma, Jr., ITS Telecommunications Theory Division and Head of U.S. Delegation to ITU-R Study Group 3
• Fireside Chat: The Reality of Building Consensus
  • Jeremy Glenn, NTIA Institute for Telecommunication Sciences (Moderator)
  • Ira Keltz, Deputy Chief/Chief of Staff, Office of Engineering and Technology, Federal Communications Committee (FCC)
  • Derek Khlopin, Deputy Associate Administrator, NTIA Office of Spectrum Management
• Technical Talk
  Sunny Wescott, CISA ISD Chief Meteorologist, U.S. Department of Homeland Security
• Panel: Measurements and Data
  The development of clutter models requires high quality, diverse, and verifiable measurement data. This panel looked at how to establish a scalable measurement framework within which organizations can capture and exchange clutter measurement data across an assorted range of systems. What commonly accepted standards are needed? How can trust be established between diverse datasets? What are the implications of aggregating disparate datasets?
  • Adrian Florea, Director of Data Science, Communications Research Centre Canada (Moderator)
  • Burak Berksoy, Director of RF Engineering, Netscout
  • Julius Fodje, Expert Member of Technical Staff, AT&T
  • Max Hollingsworth, University of Colorado Boulder and ITS
  • Frank Lind, Geospace Technology Lead and Deputy Research Director for SpectrumX, Massachusetts Institute of Technology Haystack Observatory
• Technical Talk: Network Planning and Deconfliction
  Chris Wieczorek, Director, Spectrum Policy, T-Mobile USA, Inc.
• Technical Talk: NSF Greenbank NRQZ Analysis of Basestation Requests
  Sheldon Wasik, Zone Regulatory Services Coordinator · National Radio Astronomy Observatory
• Panel: Using Clutter Models
  Incorporation of clutter models in system-level scenario analysis requires careful attention to both the details of the model itself and the system- and scenario-specific considerations that may require additional tuning or corrections. For example, it may be necessary to incorporate corrections for antenna patterns, clutter depth or angle, or extrapolation of other model parameters to apply the most appropriate clutter model to a scenario that has differences in geometry or other factors from those driving the measurements and assumptions used to develop the original model. This panel discussed how systems, sharing architectures, and studies use clutter model outputs, and how models can be adapted to scenarios that may not share the exact assumptions that were used in their development.
  
  • Tony Rennier, Founder and CEO, Foundry Inc. (Moderator)
  • Martin Doczkat, Chief of the Technical Analysis Branch, Office of Engineering and Technology, FCC
  • Kasey Pugh, Defense Information Systems Agency (DISA), Program Executive Office Spectrum (PEO-S) TARDyS3
  • Todd Summers, Director of Research and Development, SoftWright LLC
  • William Young, Subject Matter Expert in Spectrum Dependent Technologies, MITRE Inc.

Thursday, June 13, 2024

• Opening Remarks
  Charles Dietlein, NTIA Institute for Telecommunication Sciences
• Technical Talk [Pre-recorded]: Frictionless Reproducibility
  David Donoho, Professor of Statistics, Stanford University
• Technical Talk: Challenges, Data/Software Sharing
  Jacobus (Kobus) Van der Merwe, Jay Lepreau Professor, School of Computing and Director Flux Research Group, University of Utah
  
• Panel: Openness, Collaboration, and Growing the Community
  The U.S. Government has ambitious plans to utilize mid-band spectrum in support of both governmental and commercial interests. In order to accomplish such goals, the roster of spectrum engineers must grow. Part of growing the workforce is educational, but part is also lowering the bar to entry to attract attention in an increasingly crowded list of technical fields. This panel will look at how embracing open source and open data can grow the number of people wanting to pursue a career in RF measurement or propagation modeling. How can increased transparency of data and tooling open the doors to more productive collaboration among government, industry, and academia?
  • Nick Laneman, Director, SpectrumX; Co-Director, Wireless Institute, University of Notre Dame (Moderator)
  • Richard Bernhardt, Vice President, Spectrum and Industry, WISPA and WinnForum Treasurer and CFO
  • Alan Rosner, Director Spectrum National Security Systems, NTIA
  • Jacobus (Kobus) Van der Merwe, Associate Professor, School of Computing, University of Utah
• Tutorial Outcomes: Building and Evaluating a Statistical Propagation Model
  • William Kozma, Jr., NTIA Institute for Telecommunication Sciences and Head of U.S. Delegation to ITU-R Study Group 3
  • Max Hollingsworth, University of Colorado Boulder and NTIA Institute for Telecommunication Sciences
• Panel: Wrap-up and Roadmap
  What are next steps? The panel moderators summarize the most important take-aways from the discussions and consider whether community consensus is possible on any well-developed idea or solution that was discussed and which areas or ideas warrant further research or stakeholder group involvement.
  
  • Jeremy Glenn, NTIA Institute for Telecommunication Sciences (Moderator)
  • Kalle Kontson, Johns Hopkins University Applied Physics Laboratory (APL)
  • William "Billy" Kozma, Jr., ITS Telecommunications Theory Division and Head of U.S. Delegation to ITU-R Study Group 3
  • Adrian Florea, Director of Data Science, Communications Research Centre Canada
  • Tony Rennier, Founder and CEO, Foundry Inc.
  • Nick Laneman, Director, SpectrumX; Co-Director, Wireless Institute, University of Notre Dame