- The FCC is casting its net wider than the specific bandwidth in response to NextNav’s petition to use the lower 900 MHz band where RAIN RFID transmissions are taking place
- FCC Chairman Brendan Carr recommended investigating different e-911 options beyond the NextNav petition
The Federal Communication Commission (FCC) is using a petition by NextNav that would affect RFID transmission to upgrade the next generation of 911 emergency calling systems that don’t rely on the relatively low 900 MHz band.
The proposal comes in response to NextNav’s push to use the lower 900 MHz band where RAIN RFID transmissions are taking place to provide a higher broadband segment that would be available without requiring other technologies’ realignment to accommodate crowding of the band.
The FCC is proposing new rules related to emergency navigation. The action follows a petition filed by NextNav last spring for a change in the alignment of the 902-928 band to enable terrestrial GPS transmissions in rescue operations to locate missing emergency responders. NextNav would allocate some of its space in that lower bandwidth for 5G communications to pinpoint a caller’s location. Re-organization of the bandwidth is the exclusive domain of the FCC.
The commission voted to open an inquiry into how the U.S. can develop terrestrial position, navigation and timing (PNT) systems using airwaves already reserved for the private sector, either in the broadcast or wireless communications industries.
NextNav’s Proposal
In April 2024, NextNav filed a rulemaking petition with the FCC to realign the band that is currently used by RAIN RFID as well as other wireless devices such as LoRa transmissions and Z-Wave. These users have raised concerns about the impact on the transmissions of these passive Part 15 devices. The rule change would permit NextNav’s 5G transmissions on that same band to create a three-level axis of location: X, Y and Z axis.
If the NextNav petition was awarded, the proposed changes could create some crowding of that bandwidth in the U.S., according to a joint statement issued by RFID industry standards organizations RAIN Alliance and AIM Global.
FCC Objective
The NextNav petition was seeking to assign a nationwide and exclusive license to itself as a single entity to overcome the fact that “the economics of building a widescale, standalone terrestrial PNT network would be insurmountable.” That would limit control of more than half of the spectrum already in use by public agencies and local and state governments to a single commercial entity.
The FCC’s latest proposal offers an alternative to modifying the mechanisms in placed for the lower 900 MHz range in the interest in improving the location accuracy of 911 calls. While NextNav offered its solution to identify location with the support of 5G gateways, the FCC is now turning its sights on technology-based options to solve the X, Y and Z axis requirement.
Carr Comments
FCC Chair Brendan Carr emphasized the need for a backup, focusing on solar storms last year that shut down some farming operations in the Midwest because GPS went out.
“Agriculture is just one facet of modern American life vulnerable to GPS disruptions. Our electric grid, our financial systems, our ports, our communications networks, our military, our driving directions…all rely on GPS to provide positioning, navigation and timing,” Carr said.
The importance for a GPS alternative was framed as economic and security issues, as China and Russia have backups for PNT services. “With this inquiry, we will explore other PNT systems that can be complements or alternatives to GPS, with an emphasis on complementary systems.” he said. “We hope this effort will engage stakeholders across government and industry to encourage the development of new PNT technologies and solutions.”
GPS, RFID Coexistence
NextNav’s proposed PNT system is designed to deploy a network of 5G New Radio (“NR”) base stations for positioning reference signals to determine location and timing based on time of arrival. The network of base stations would be coordinated from one of the stations that serves as an absolute time source, presumably to be built out and supplemented over time as use cases and demand dictates the need for additional 5G density.
NextNav’s supplemental submission proposed rule language changes to regulate that operations currently authorized in the areas of the spectrum that would not cause harmful interference to the proposed PNT system. The system would use the two band segments NextNav is targeting—902 – 907 MHz and 918-928 MHz—to be reconfigured to avoid interference from PNT systems.
The use of 5G position referencing signals concerns those whose technology relies on the open band width. A question raised by the GPS Alliance (GPSIA) was whether a new terrestrial navigation system could function effectively with less than a 10 MHz dedicated downlink frequency, possibly with somewhat lower performance standards.
Toll Survey
NextNav said based on its own simulations that GPS operations could coexist with deployed RFID systems, citing a survey of the International Bridge Tolling systems (IBTTA) surveyed members for input on implications and risks to existing toll operations and systems.
The survey toll operators asked:
- Do the proposed commercial applications in the spectrum present risks of interference for existing toll applications?
- Is there a risk of signal bleed-over into the tolling spectrum?
- Will a narrowed range require toll system reader upgrades to restrict toll communication bandwidth more precisely?
For those who fully completed the survey, 71 percent were toll operators, 18 percent RFID equipment and systems suppliers, and 11 percent technical consultants and other service providers. Movements toward interoperability among many tolling organizations, the most popular tolling protocols in use and supported includes UHF RFID 6C, TDM, and SeGo, with 36 percent of respondents indicating that they supported other protocols in their current operations.
The petition would reduce the frequencies available for RFID and tolling by at least 20 percent. And the spectrum restructuring with 5G in operation over the lower 900 MHz bandwidth would result in more missed RFID transponder reads.
For toll operations the consequences would be lost revenue from uncollected image-based transactions; greater cost associated with license plate lookups and invoicing, customer service issues with valid electronic toll account holders being billed by invoice; and erosion of customer confidence and trust in the public revenue systems’ ability to perform accurately and correctly.
RFID Concerns Raised
Two other concerns raised included degraded safety system performance for motorists and road operators to avoid traffic crashes, increasing fatalities, injuries, and property damage; and reduced availability of reliable real-time RFID data and challenges for the growing congestion management and controlled access strategies (e.g., managed and express lanes) being employed in many regions.
Concern among GPSIA members—which include Apple, Garmin, John Deere, Lockheed Martin, and TrustPoint—and the RAIN Alliance is the cost of mitigation efforts required by tolling systems and RAIN RFID systems to ensure proper use of their own technology.
NextNav View on FCC Focus
NextNav officials see an opportunity in the latest FCC ruling as the federal agency acknowledges the importance of new Next Generation (NG911) interoperability requirements for the interstate transfer of 911 traffic.
“We applaud the commission’s engagement with stakeholders across government and industry and its commitment to a ‘system of systems’ approach that includes both space- and terrestrial-based technologies to build redundancy into America’s critical infrastructure,” said the company’s CEO Marian Sorond. “At NextNav, we’re committed to being part of the solution.”
Sorond noted leveraging low-band spectrum in the band where NextNav already holds extensive licenses, their approach would provide terrestrial backup to GPS that harnesses the power and scale of 5G—without requiring taxpayer funding.
“As a leader in PNT innovation, we’re looking forward to working closely with the Chairman, Commissioners, and broader stakeholder community to accelerate the deployment of resilient, complementary technologies that build important redundancies into a system we rely on every day,” she said.
GPSIA Reaction
GPSIA Executive Director Lisa Dyer viewed the FCC actions as a good sign for their members.
“It shows that there’s a lot of interest in what they offer,” said Dyer. “Other folks in the lower 900 megahertz per the that have come in and said ‘hey we’re concerned about this this impacts our current operations and we don’t know that their proposal is going to mitigate our concerns about interference’.”
Due to basic 911 system outages, there are many issues to work out with the existing communications infrastructure. GPSIA noted each of the FCC commissioners highlighted the benefits GPS brings.
“It’s a good conversation for the FCC to be having… about complementary PNT, as well as its recognition that getting this right requires a ‘whole-of-government’ approach,” said Dyer. “Existing local terrestrial and complementary PNT satellite systems are the most feasible and achievable options today and in the near future.”
Key Emergency Tool
GPSIA member companies provide location services for people during emergencies, particularly when terrestrial systems are unavailable in areas without cellular or Wi-Fi services and subsequent to natural disasters, such in the aftermath Hurricane Helene last year.
These services extend the capabilities of GPS to the MSS portions of L-band and alliance members stressed they should be included in any conversation about public safety. Apple’s Emergency SOS via Satellite, Messages via Satellite and Garmin’s inReach services have and are saving lives, noted Dyer.
“We look forward to participating in the proceeding and highlighting the need for a modernized GPS constellation, as well as satellite systems with orbital, spectral, and signal diversity, that complement GPS,” said Dyer. “There are a lot of great ideas on paper always. The question is, how quickly could they come to fruition.“