Planning for 4.9 GHz Spectrum Changes (2025)
Chapter: 2 Documentation of Research Activities
2 Documentation of Research Activities
Blue Wing has extensive knowledge in the 4.9 GHz spectrum arena. Additionally, we performed extensive research regarding the long history of 4.9 GHz spectrum changes to better document the timeline for all stakeholders.
2.1 History of 4.9 GHz Band (4940–4990 MHz) — Task 1
The first task at hand was for us to capture and convey the history of the 4.9 GHz spectrum, along with the proposed new rules.
The completion of Task 1 provided a comprehensive outline of the history of 4.9 GHz band. Blue Wing has included the below excerpts from the 4.9 GHz research memorandum titled NCHRP Project 23-28, Planning for 4.9 GHz Spectrum — Task 1 History of FCC Actions Regarding the 4.9 GHz Band dated January 8, 2024.
2.1.1 4.9 GHz in 2002
In 2002, when the commission allocated the 4.9 GHz band for fixed and mobile services in support of public safety, it envisioned that the band would support new broadband applications, such as high-speed digital technologies and wireless local area networks for incident scene management, dispatch operations, and vehicular/personal communications. Since that time, to be eligible for a 4.9 GHz license, an entity must provide public safety services. This eligibility includes state and local government entities, as well as non-governmental organizations, that operate their wireless systems solely to transmit communications essential to the provision of services having the sole or principal purpose of protecting the safety of life, health, or property.
2.1.2 4.9 GHz in 2003
The original rules adopted in 2003 for the band permitted broadband mobile operations, fixed hotspot use, and temporary fixed links, all on a primary basis in the band, as well as fixed point-to-point operations on a secondary basis. The Federal Communications Commission (FCC) established a “jurisdictional” geographical licensing approach for operations in the band, whereby licensees are authorized to operate in those geographic areas over which they have jurisdiction and are required to cooperate in use of the spectrum. Regional plans and frequency coordination for the 4.9 GHz band were allowed but were not required under the rules.
2.1.3 4.9 GHz in 2009
In April 2009, the FCC modified the original rules to allow permanent fixed point-to-point broadband operations on a co-primary basis with other uses in the 4.9 GHz band.
2.1.4 4.9 GHz in 2012 — The FCC Fourth Report and Order and Fifth Further Notice of Proposed Rulemaking
In 2012, the FCC issued a follow-up Fourth Report and Order and Fifth Further Notice of Proposed Rulemaking (NPRM) regarding the 4.9 GHz spectrum. This NPRM sought additional comments and recommendations on coordination, eligibility, licensing, the band plan, power and antenna gain, aeronautical mobile use, and the potential role of the 4.9 GHz band in relationship to the 700 MHz nationwide public safety broadband network being planned by FirstNet.
Nothing came from the Commission’s 2012 Further Notice of NPRM, but the FCC eventually issued a Sixth Further Notice Of Proposed Rule Making in 2018. This document, citing what the commission believed was low usage of the band, proposed an additional series of changes to the band to encourage development.
2.1.5 4.9 GHz 2020 — The FCC’s Sixth Report and Order and Seventh Further Notice of Proposed Rulemaking
The FCC’s 4.9 GHz Sixth Report and Order and Seventh Further Notice of Proposed Rulemaking, released on October 5, 2020, in WP Docket No. 07-100, represented a significant change in the way that the public safety spectrum is allocated. By assigning responsibility for spectrum use and management to states under a lease or spectrum manager format, the FCC took a step toward utilizing the spectrum management tools traditionally used for private spectrum in the public safety space. Although the decision has some similarities to the 700 MHz and 800 MHz National Public Safety Planning Advisory Committee plan allocation formats, the ability to intermix a variety of public safety, non-public safety, wideband, and narrowband operations controlled by a band manager or through leases issued by a state is not totally unfamiliar to many public safety entities. Since this document generated a significant amount of interest in the band on the part of state transportation officials, the details contained therein are explained more fully than prior orders in the proceedings.
2.1.6 4.9 GHz 2024 — The FCC’s Current Proceeding
FCC’s 4.9 GHz Eighth Report and Order, released on October 22, 2024, in WP Docket No. 07-100, represents a significant change in the way that public safety spectrum is allocated. By assigning responsibility for spectrum use and management to a band manager under a lease and spectrum manager format, the FCC has taken a step toward utilizing the spectrum management tools traditionally used for private spectrum in the public safety space.
The FCC will create a nationwide “overlay” license, which will be assigned to a band manager. The band manager will be responsible for:
- Entering into a nationwide spectrum sharing lease with FirstNet;
- Frequency coordination and interference protection for incumbent licensees;
- Managing the spectrum sharing agreement with FirstNet;
- Encouraging technological innovation in the band; and
- Filing an Annual Report with the FCC.
The band manager may not be a system operator.
A committee selecting the band manager, the criteria for the band manager’s selection, the specifics of the band manager’s responsibilities, how the band manager gets compensated, etc. will be handled by the FCC’s Public Safety and Homeland Security Bureau, in conjunction with the FCC’s Wireless Bureau.
For incumbent licensees: (1) incumbents may continue to operate indefinitely, with their existing technology (or any other technology for that matter); (2) there is a full freeze on new or amended licenses for incumbents (and no new licensees); and (3) pursuant to an FCC Public Notice released on December 9, 2024, geographic licensees had until June 9, 2025 to go into the FCC’s Universal Licensing System and designate the location and technical parameters of their existing operations (after which period the FCC will cancel the geographic license and issue a site-specific license).
Regarding the type of operations permitted in the band, the band remains exclusively for public safety operations.
The FCC declined to adopt a harmful interference standard and declined to specify that incumbents must use a specific type of technology.
2.2 Outreach Plan — Task 2
The completion of Task 2 resulted in the development of the outreach plan that focused on reaching out to the state and local transportation and public safety interests, as well as industrial, business, and commercial interests which may have access to the band in the FCC’s final plan.
In this section, Blue Wing is providing excerpts from the outreach plan titled NCHRP Project 23-28, Planning for 4.9 GHz Spectrum Task 2 — Outreach Plan, dated March 1, 2024.
Blue Wing researched and compiled outreach contacts from the 4.9 GHz industry representatives with assistance from American Association of State Highway and Transportation Officials, state statewide interoperability coordinator (SWIC) representatives, public safety, and transportation leaders, and social media (i.e., LinkedIn targeting Transportation Industry). In addition, we developed and conducted a 4.9 GHz Survey of transportation and public safety agencies that focused on gaining knowledge about their current and potential future uses of the band through dissemination of a survey link. The data was analyzed and supported the continued outreach for hosting a Virtual Roadshow that was held on February 29, 2024.
The outreach efforts focused on
- Introducing the 4.9 GHz research project and providing valuable insight into the level of entities knowledge of 4.9 GHz, the FCC proceedings, including entities involvement.
- Exploring the uses of the band and interest in present and future use of the band.
- Determining the desired level of involvement in the future of the 4.9 GHz band.
- Developing and proposing long-term plans for use of the band by users.
- Identifying what is needed to encourage more robust 4.9 GHz product development at more reasonable prices by the manufacturing community.
- Exploring what structural and regulatory formats will best encourage the sharing of the band (both shared systems and non-interfering shared spectrum).
- In the case of potential shared systems, identifying what formats have been most successful in ensuring full access to the spectrum by participating entities in a reasonable manner in a fair economic model.
These outreach strategies supported the development of a narrowed list of useful methodologies and formats for each of the potential options that were being considered by the FCC prior to the issuance of the commission’s October 2024 Eighth Report and Order.
It is important to note that the current and potential equipment manufacturers were included in the research and survey analysis. Part of the failure of the band to develop, thus far, has been the result of manufacturers having too small an ecosystem to sell into, resulting in equipment that is too expensive and too narrowly tailored to see exploitation by any but the largest municipalities.
2.3 Scenarios — Task 3
The continued research and interaction with stakeholders of the 4.9 GHz band resulted in the completion of Task 3. Blue Wing developed plausible current and future potential scenarios for licensing and allocation of the 4.9 GHz spectrum, as it relates to DOTs and public safety entities, as well as other current and future 4.9 GHz band users.
The plausible current and future scenarios that were presented include conditions that could accommodate, constrain, and/or severely reduce state DOT’s use of the spectrum.
Blue Wing has included the excerpts below from the potential scenarios document titled NCHRP Project 23-28, Planning for 4.9 GHz Spectrum Task 3 — Potential Scenarios that was dated April 16, 2024.
At the time of the submittal of Task 3, Blue Wing presented the following two scenarios which were potential options prior to the issuance of the Eighth Report and Order, as outlined below:
- Scenario 1 — The FCC’s rules provide that existing licensees may continue to operate until the rulemaking has been completed. Thus, to the extent that a state DOT is a licensee, it may continue to operate as it has before and perhaps expand its existing operations.
- Scenario 2 — Because of the licensing freeze, any new operations by state DOTs must be under the current authorization of an existing licensee. As most states have 4.9 GHz licenses, and many of those licenses authorize statewide operations, it is possible that a state DOT can operate under such licenses, with the permission of the license holder.
The following are the four scenarios that were dependent on the outcome of the FCC proceeding that were previously presented for consideration:
- If the band is allocated to a single wireless infrastructure provider (like FirstNet in the 700 MHz “D Block”), an ecosystem of equipment is developed, offering interoperability across multiple users, both public safety and non-public safety. In this formation, users are limited to those services permitted and coverage areas offered by the single wireless provider. In this format, lease payments or monthly charges should be expected.
- If the band is allocated to multiple wireless infrastructure providers, requiring the use of the same interoperable technology (like the Citizens Broadband Radio Service band), both public safety and non-public safety is possible. In this formation, users are limited to those services permitted and coverage areas offered by the wireless providers. Lease payments or monthly charges should be expected.
- If the band is allocated in a format which permits multiple users (both public safety and non-public safety) to implement their own systems, there would be certain requirements for prevention of interference and public safety priority and preemption. In this format, users would make their own decisions regarding coverage areas, etc., and the types of services discussed previously, with the potential that users could share systems with both public safety and non-public safety users. Such sharing has occurred pursuit to waivers in the 800 MHz band, where numerous non-public safety eligibles have been permitted to become users on public safety radio systems. The major change at 4.9 GHz in this scenario would be a stronger management and interoperability situation (along with the eligibility expansion). However, it is possible that there will need to be some kind of payment structure to fund the band manager.
- Some public safety interests had been lobbying the FCC for continuation of public safety only access, albeit with enhanced licensing/coordination rules to better demonstrate the actual usage in the band, and essentially no other changes. Under this scenario, State DOTs would have the same access as previously permitted, with no sharing with non-public safety eligibles.
2.4 Strategies and Outreach Summaries — Task 4
The Blue Wing team contacted state DOT agencies, SWIC, 4.9 GHz public safety users, and DOT professionals through email. In addition, the team also posted its direct email on two different LinkedIn groups: (1) Joint Council on Transit Wireless; and (2) Public Transit. The Blue Wing team followed up with those entities seeking additional information and/or interested in participating in a webinar, held on February 29, 2024. Further information gathering was performed at the International Wireless Communications Expo (IWCE) that took place the week of March 25, 2024. During this key industry event, two 4.9 GHz panel sessions were held.
There were 19 respondents to the targeted emails, and 12 participants in the February webinar. The information gathered served to enhance the project research and results.
2.5 Proposed Themes and Concepts for Communication Materials — Task 5
The objective of the Task 5 deliverable was to identify and provide adequate detail on how state DOTs and other transportation agencies can disseminate the information gathered and provided during NCHRP Project 23-28, including effective training and education strategies.
The Proposed Themes and Concepts for Communication Materials document titled NCHRP Project 23-28, Planning for 4.9 GHz Spectrum Task 5 — Proposed Themes and Concepts for Communication Materials was dated September 30, 2024.
Our intent was to present options to leverage a variety of tools, techniques, and methodologies to facilitate efficient and effective development and communication of training, and educational materials. However, those options were developed prior to the issuance of the Commission’s Eighth Report and Order and thus were based upon knowledge available at that time.
During this task, the Blue Wing team addressed (1) educational materials for a variety of levels (management, administrative, technical, etc.); (2) implementation options, including positive and negative aspects of each; and (3) pathways and strategies for implementation of the chosen strategy. The objective of this task and deliverable is to identify and provide adequate detail on how state DOTs and other transportation agencies can disseminate the information gathered and provided during NCHRP Project 23-28, including effective training and education strategies.
This task sets the stage for building a stronger communications platform for the collections of documents and sharing of pertinent information among all stakeholders.
