Summary
The National Institute of Standards and Technology (NIST) Communications Technology Laboratory (CTL) was established in 2014 to unify the communications research and development (R&D) efforts occurring across NIST. CTL is divided into five divisions: three based in Boulder, Colorado, and two based in Gaithersburg, Maryland. The National Academies of Sciences, Engineering, and Medicine (National Academies) were asked by the director of NIST to assemble an expert panel to assess the work of the three divisions based at the Boulder facility: the Public Safety Communications Research Division (PSCR), the Radio Frequency Technology Division (RFTD), and the Spectrum Technology and Research Division (STAR), in fiscal year (FY) 2025.1 The assessment encompasses four primary objectives:
- assess CTL’s technical programs, comparatively against world-class research, and its adequacy to reach NIST’s stated objectives;
- assess CTL’s scientific expertise comparatively to leading experts and adequacy to reach its stated objectives;
- assess the adequacy of budget, facilities, equipment, and human resources; and
- assess the effectiveness of CTL’s dissemination of its program outputs, in terms of direction toward stakeholder needs, effectiveness of methods, and monitoring of stakeholder use and impact.
The full statement of task is included in the introductory chapter of this report. The expert panel structured its review by division, and developed overarching key conclusions and recommendations, as well as division-specific conclusions and recommendations.
PUBLIC SAFETY COMMUNICATIONS RESEARCH DIVISION
The PSCR aims to “accelerate the adoption of critical communication capabilities for first responders” through five research portfolios: Mission Critical Services (MCX), User Experience (UX), Location-Based Services (LBS), Uncrewed Aircraft Systems (UAS), and the Innovation Lab. These five program areas provide services and technical expertise to the public safety community and related industries. Such service is intended to accelerate applicabil-
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1 Complementary FY 2025 National Academies’ assessments are available of the NIST Center for Neutron Research as well as the Gaithersburg divisions of the Physical Measurement Laboratory.
ity of communications technologies for public safety use cases in parallel to commercial availability for the U.S. consumer. The PSCR appears to be unique among federal laboratories working on public safety communications because of its focus on local first responders, creating an ecosystem where these workers have a meaningful voice informing interdisciplinary communications research.
The MCX portfolio is meeting its technical objectives, notably with its leadership in the replacement of Land Mobile Radio (LMR) standards for push-to-talk radios with more advanced technologies on mobile broadband networks. The MCX group developed trusted and provable application readiness, specifications, equipment readiness testing, and laboratory test certification, and then transferred the work to commercial testing and evaluation companies.
The UX group takes a first-responder training point of view to develop augmented, virtual, and extended reality, heads-up displays, haptics and audio cues, and user experience research and testing methodologies, for example, simulating the experience of a firefighter entering a room. Obtaining feedback from intended end users in a frequent and convenient manner about routine and emergency uses is key to conducting successful applied research and technology transfer. The UX group has significant potential for stakeholder impact by focusing on NIST measurement science and developing guidelines to evaluate operations of third-party products in its mockup of real-world settings.
The LBS portfolio focuses on indoor positioning, a long-standing engineering challenge for first responders, particularly in the z axis (vertically). The team is constructing an instrumented z-axis facility, which will enable R&D, testing, and unique dataset production by groups internal and external to NIST to evaluate indoor positioning solutions.
The UAS group sponsored eight prize competitions from 2018 to 2025 to advance capabilities of uncrewed aircraft systems for emergency response operations. This research area appears to align well with NIST’s metrology strengths, such as the use of standardized test methods to evaluate the UAS solutions from different competition teams, and has so far differentiated itself from other first responder–related UAS efforts nationwide.
The Innovation Lab supports the computing, networking, and radio needs of other PSCR portfolios and CTL divisions. It operates multiple LMR systems and a long-term evolution base station deployed in a test range, and it has a van outfitted with a radio tower for drive testing and high-elevation outdoor deployment.
The PSCR’s expertise across the portfolio of projects in MCX, UX, LBS, UAS, and the Innovation Lab supports its objectives reasonably well despite such a small number of staff. The MCX’s success in transforming an unsolved engineering and standardization problem into a final technology transfer stood out. The UX staff adequately supports its technical programs, but the group could benefit from additional staff to support a test and evaluation setup with commercial partners to assess its UX guidelines. Similarly, the LBS could better confront the numerous unsolved problems in signal processing and engineering with a larger team of researchers who have expertise in areas such as radio frequency (RF) propagation, optics, signal processing, radar, imaging, and communications. Adding more PhDs with relevant backgrounds in applied research could contribute to research depth and breadth in the PSCR. This could accelerate adoption of critical communication capabilities for first responders via enhanced cross research portfolio collaboration.
The PSCR facilities are of high quality and a major asset to the division. The equipment is likewise excellent, including the networks and capabilities provided by the Innovation Lab. A plan for maintenance of equipment that is grounded with stakeholder requirements and funding sources is needed.
The PSCR has maintained high-quality stakeholder engagement. It hosts a major public innovation summit that draws public safety organizations, industry, academia, and government partners from around the United States and across the world and serves as an example of how other parts of NIST could transfer research outputs, identify new problems, and market their work. The PSCR also performed a comprehensive survey and semi-structured interviews with the public safety community, publishing its findings in a 2018 NIST report with additional volumes published through 2023. It is developing a roadmap to address issues identified by stakeholders: budget and logistics, technological needs, and information gaps.
The PSCR subpanel’s conclusions and recommendations are presented in Chapter 2. The PSCR subpanel recommends that the PSCR (1) consider updating research on the transition from LMR to newer technolo-
gies; (2) require projects to specify anticipated outcomes in measurement sciences, standards development, accelerating adoption, and reusable datasets; (3) increase the ratio of personnel with PhDs; (4) analyze costs of system upkeep and consider how to allocate those costs; and (5) consider monitoring value beyond targeted stakeholders.
RADIO FREQUENCY TECHNOLOGY DIVISION
The RFTD has four research groups: the Electromagnetic Fields Group (traceable electromagnetic field strength measurements for international standards and electromagnetic compatibility [EMC] evaluations), the Guided Wave Electromagnetics Group (fundamental electromagnetics research for advanced wireless communications), the High-Speed Waveform Metrology Group (measurement science for high-frequency communications and 5G/6G networks), and the Superconducting Electronics Group (quantum technologies for voltage standards, quantum waveform synthesis, and RF metrology). The division has key technical strengths in foundational metrology with capabilities competitive with leading national metrology institutes (NMIs)—for example, Josephson standards, and RF power and scattering-parameter measurements. Work in the RFTD impacts all time-critical systems across national security and civilian infrastructure domains, improving technology from cell phones to computer chips. The RFTD transformed RF probe calibration into atom-based primary standards, reducing uncertainties and positioning the United States as the global leader in RF quantum sensing. It has led innovation in measurement science that has launched entirely new industries—for example, Rydberg sensing with approximately 25 companies and $100 million in commercial activity based on NIST technology. It operates at the appropriate early technology readiness level, with successful technology transfer to industry implementers. The division contributes to several standards (Next Generation Communications [NextG] Channel Model Alliance, Third Generation Partnership Project, and the Institute of Electrical and Electronics Engineers). It is developing new technologies with strong external collaborations positioned to significantly contribute to future industry needs—for example, hot qubit metrology, the Creating Helpful Incentives to Produce Semiconductors (CHIPS) and Science Act magnetic materials, and 5G/6G EMC frameworks.
The RFTD has committed staff with technical depth. It possesses strong scientific expertise across its mission areas, with recognized contributions in quantum sensing, high-frequency electronics, and calibration sciences. Staff have pioneered measurement methods including Rydberg atom electrometry, electro-optic sampling to 1 terahertz, and advanced channel sounding methodologies. Early career researchers demonstrated enthusiasm and strong capabilities, contributing to a vibrant research environment. Two areas for improvement are (1) greater connection with universities outside of Colorado and (2) succession planning or knowledge-transfer protocols, given both an aging workforce and the specialized nature of metrology expertise. Greater development and hiring of technicians could also better balance the workforce of graduate students, early career staff, and senior research staff.
The division’s facilities face significant infrastructure challenges that actively compromise its ability to provide reliable national measurement standards. Multiple facilities experience planned power interruptions and unplanned power failures, uncontrolled temperature issues affecting calibration chamber stability, and inadequate environmental controls requiring makeshift solutions like open windows for equipment cooling.
The division demonstrates competence in traditional NMI dissemination methods including journal publications, conference presentations, technical reports, and standards development. Notable technology transfer successes include automation of the Josephson voltage standard, enabling adoption by other NMIs; development of primary standards lab capability within the Air Force Metrology and Calibration Program; open-source Open Radio Access Network (O-RAN) testbed tools; and NextG Channel Model Alliance data repository.
The RFTD subpanel’s conclusions and recommendations are presented in Chapter 3. The RFTD subpanel recommends that (1) the RFTD develop new measurement capabilities to address current industry needs; (2) NIST address infrastructure failures through backup power and environmental control remediation; (3) the RFTD conduct a strategic industry stakeholder needs assessment; (4) the RFTD enhance its impact assessment; (5) the RFTD implement workforce practices that optimize resources and plan for technical workforce succession; and (6) CTL perform a workforce metrics analysis.
SPECTRUM TECHNOLOGY AND RESEARCH DIVISION
Launched in 2021, STAR is a relatively new division of CTL that works to increase the availability of spectrum for commercial use without impacting military applications. It contains three primary research groups: (1) Applied Systems Metrology, which develops technical foundations for spectrum science and measurement techniques for closed-box RF systems; (2) Fiber Sources and Applications, which develops fiber-laser frequency combs for a variety of precision measurement applications; and (3) Shared Spectrum Metrology, which performs research on wireless coexistence, EMC, spectrum sensing and noise, and interoperability for the 5G O-RAN. Together, these groups help ensure that the U.S. infrastructure for communications, spanning mobile phones to GPS, operate correctly and without interferences as the public expects.
Technical achievements of STAR include groundbreaking work in optical comb time transfer, yielding synchronization accuracies of less than a femtosecond. Spectrum sensing and sharing work is also of high quality, including both theoretical and field-tested practical capabilities. Expanding CTL’s research using aerial capabilities (e.g., drones) can address metrology and standards needs in a technology area of growing importance. CTL’s advanced RF instrumentation, calibrated data collection, and interference modeling provide essential tools to quantify and mitigate RF interference, ensuring measurement integrity. STAR has a wide range of stakeholders and collaborators, including government, industry, standards organizations, and academia. New directions that could be impactful for the division and its stakeholders include building off the Citizens Broadband Radio Service spectrum sensing program and branching into new bands, developing RF digital twins for controlled simulation or emulation, and developing standards for digital twins used in artificial intelligence (AI)-native wireless for 6G across the commercial industry.
The scientific expertise within STAR is of very high quality and fits the variety of technical programs conducted by a range of researcher types, from early career scientists and engineers to midlevel staff, to senior staff of international repute. One strength of the division is the support of management for principal investigators to propose high-risk, high-reward, curiosity-driven research, which is essential for the continued vitality of the science and engineering of a national laboratory. The division staff would be expected to grow as spectrum sensing becomes more critical and to expand the division’s expertise into needed areas like AI-native wireless/RF digital twins.
The facilities and laboratories at STAR are well equipped and maintained, and field-testing facilities are well designed. Laboratory equipment is generally state of the art, but the absence of backup power for some laboratories is a problem. Additional facilities may be required if STAR takes on future work from any government sponsor that requires controlled access. The division has one secure facility but no associated secure laboratory.
The division’s publication record is strong, producing journal articles, conference presentations, technical reports, standards, validated datasets, and even short courses for the community at large. Three gaps were identified in STAR’s dissemination strategy: collaboration with other government entities to share data, widely sharing and evaluating validated data, and technology transfer.
The STAR subpanel’s conclusions and recommendations are presented in Chapter 4. The STAR subpanel recommends that STAR (1) better engage with the U.S. Department of War (DOW), National Science Foundation, and commercial stakeholders; (2) investigate the use of techniques beyond radiometric detection for spectrum sensing; (3) contribute to the technical evaluation and gap or security analysis of emerging technologies; (4) better define, track, and value its technology transfer strategy; (5) better share validated data; (6) lead the development of standardized frameworks for use of digital twins in AI-native 6G wireless systems; and (7) employ its radiometry expertise to space research applications.
OVERARCHING CONCLUSIONS AND KEY RECOMMENDATIONS
A set of overarching conclusions and key recommendations that spans all the CTL divisions under review is as follows:
Overarching Conclusion 5-1: The Communications Technology Laboratory (CTL) research is of top quality. It has profound implications for the relevant research communities, industries, and government stakeholders. Continuing to pursue new topic areas within CTL’s strengths in measurement science is critical to meeting stakeholder needs.
Overarching Conclusion 5-2: Even with limited research staff, the Communications Technology Laboratory’s in-house scientific expertise is among the best in the field. However, hiring more researchers with diverse backgrounds and educational lineage from across the country as permanent staff will advance multiple areas. In particular, additional PhD researchers in the Public Safety Communications Research Division could help to accelerate application of new technologies for community use cases.
Overarching Conclusion 5-3: The existing Communications Technology Laboratory (CTL) facilities in Boulder are maintained and utilized to the best of the CTL staff’s ability given available resources. Some infrastructure issues, particularly the lack of reliable power supply have interrupted research and experimental work. With ever-growing research and development infrastructure and service maintenance cost, current resources for infrastructure repair and improvement are insufficient, and CTL needs more capital investment to repair, improve, and expand its research facility.
Overarching Conclusion 5-4: The dissemination of Communications Technology Laboratory (CTL) program outputs via publications, presentations, and certain datasets is aligned with best practices for industry standards and academic expectations. There is insufficient coordination with institutions who are working in similar problem spaces (e.g., the National Telecommunications and Information Administration), where CTL can take the lead on metrology and inform standards. CTL curation of additional open radio frequency, public safety, and spectrum sharing and sensing datasets could support stakeholder needs. Opening datasets and sharing them with the greater open research community is a mountainous effort but of great value. No group is better suited and placed to undertake this than CTL.
From the above overarching conclusions stem these key recommendations:
Key Recommendation 5-1: The Communications Technology Laboratory (CTL) should examine the division-specific recommendations for research topic growth areas that would advance CTL’s mission and leverage its technical strengths.
Key Recommendation 5-2: The Boulder-based divisions of the Communications Technology Laboratory (CTL) should engage with a wider range of universities and students to supplement the recruitment opportunities presented by the Professional Research Experience Program.
Key Recommendation 5-3: Communications Technology Laboratory (CTL) leadership should prioritize addressing backup power needs for critical instruments and experiments, given the frequent planned and unplanned power outages at the Boulder campus, and its negative impact on calibrations, experiments, and the CTL mission.
Key Recommendation 5-4: The Communications Technology Laboratory should build on its success in hosting and curating open, validated datasets for research use. Areas of growth include sharing reus-
able datasets from the Public Safety Communications Research Division’s User Experience portfolio, analyzing how datasets support industry development in the Radio Frequency Technology Division, developing reliable data in new areas of the Spectrum Technology and Research Division’s work such as for digital twins, and developing shareable data from otherwise inaccessible datasets like those containing various forms of controlled information.
