In the United States the federal government regulates how wireless spectrum is used. Groups of radio frequencies, called “bands,” are allocated to some combination of government, commercial and open use. There are some bands restricted for the military, some that are licensed exclusively to private operators (like cellular network providers) and some that are unlicensed, meaning that anyone can manufacture, sell and operate devices on those frequencies.
It is relatively uncommon to make changes to the established frequency allocations, but because technology is continually evolving, it makes sense from time to time for the government to consider making a change. You may recall a number of years ago when the government decided to sunset analog television broadcasting, since digital TV was far more spectrally efficient.
The FCC reallocated the 700MHz band that previously housed analog TV channels 52-69, to increase the total spectrum for cellular communications. In that case, private companies bid for exclusive use of frequencies within the band. The government raised nearly $20B from these auctions — primarily from AT&T & Verizon, who repurposed the spectrum for cellular LTE. It bears consideration that a 20 MHz segment of the band was reserved for emergency services, but was unable to achieve the minimum bid requirement of the government during the auction. Bidding for more capitalist use cases was fierce, but “common good” must not have passed the corporate profitability test.
Back in April of this year, NextNav, a publicly traded company that offers position, navigation and timing (PNT) services submitted a petition to the FCC to reallocate the 915 MHz band of wireless spectrum. NextNav claims that this part of the radio spectrum, which includes frequencies between 902 and 928MHz is underutilized and would be better served by allocating the spectrum for private commercial use. They further argue that the spectrum is ideal for creating redundant PNT services to those relying on GPS.
Without question, GPS has been transformational across all segments of society. In NextNav’s petition, they point out that economists estimate that GPS has created at least $1 trillion dollars in economic impact. GPS relies on highly precise radio transmissions between satellites and the ground. Because we can understand with extremely high precision the timing of radio signals, when we have a device that connects with at least 3 satellites simultaneously, we can triangulate our position, based on the received transmission from each. Anywhere on the planet, if we have a clear line of sight to the sky, we can passively, and at no transaction cost, know exactly where we are.
We do not always have that unobstructed view of the sky, and so industry has come up with creative hacks that help us to maintain knowledge of our exact location, even when in our car or in a building. Primarily, we augment GPS position with other “known” locations from which we can also conduct similar radio wave timing calculations. Cell towers are in fixed positions that are known and immobile, and so with a similar approach to GPS triangulation, we can also do cellular triangulation to get a reasonable estimate of position.
There are sources of error — especially when you consider that for signals that are transmitting predominantly horizontally (from tower to phone) versus vertically (from phone to the sky), there are far more obstacles (trees, buildings, walls, hills) that reflect or bounce or otherwise impact the wireless radio path. These create fluctuations in signal timing, which translates into position inaccuracies. The more obstructions, or deeper into a building you go, the lower the accuracy.
NextNav’s core business is to develop and sell competing PNT technologies that solve many of the indoor positioning challenges of today. Their tech can provide information about altitude (e.g. what floor of a building are you on), which 2D GPS positioning cannot. And they posit that providing far more accurate indoor navigation would unlock new use cases and drive new innovations.
The FCC’s role is to consider this petition for rulemaking against the current use of the 902-928 MHz band. Prior to 1985, this segment of the wireless spectrum was reserved for military communication, and was primarily used by the Navy. In 1985, the government rewrote the rules to add significant new allowances for this frequency band.
The government recognized a need to allocate spectrum for Industrial, Scientific and Medical (ISM) applications. The 915 MHz band became known as the ISM band. If you have a pacemaker with wireless monitoring, it is likely operating in the ISM band. Many industrial control systems and asset monitoring systems utilize this spectrum. This band is used for radar wind monitoring for weather prediction, for outdoor sensor networks, industrial heating applications and medical telemetry for patient monitoring. The spectrum is a hotspot for IoT applications, including the PNT applications that NextNav creates.
Entire industries are built around RFID (Radio Frequency Identification Devices), which takes advantage of the allowance for unlicensed devices to operate under FCC Part 15. Most RFID applications rely on ultra-low cost tags that cost fractions of pennies to make, and can be deployed at massive scale, for example for theft prevention in retail stores. Because the ISM band requires no expensive spectrum license, that enables a significant group of RFID applications to be feasible in the market.
One of the most promising new wireless platforms in the ISM band is LoRa. LoRa networks, short for Long Range, are enabling new capabilities in asset tracking and management, smart agriculture and industrial automation, among other areas of IoT. LoRa satisfies applications that take very simple, discrete measurements, often at highly infrequent time intervals, and from devices that may need to run off a battery for 5-10 years. An example might be taking a soil moisture reading twice a day in a rural field. Operating in an unlicensed band, once again, enables use cases to thrive that would not generate enough data to justify the typical costs of cellular plans. In fact, anyone can set up a LoRa network inexpensively and then have zero wireless data costs at all.
Innovation is happening because innovators can simply buy an RFID or LoRa or other 915MHz radio and begin hacking and experimenting with new products and business models. There are some restrictions on use of the spectrum, but they are relatively easy to manage (and there are third party services to verify compliance under FCC Part 15).
● New devices must not interfere with legacy military use. This is fairly straightforward by keeping transmit power levels low, as is standard for RFID and LoRa.
● Amateur radio can also operate on this band, but not interfere with ISM applications, which are granted primary use of the spectrum.
Clearly, the 915MHz band is not underutilized, as NextNav would suggest. And if you consider LoRa in particular, it is a market that is seeing exponential growth. One day, LoRa may have outdoor coverage that is similar to the cellular and wifi networks of today – but for low-power, discrete sensor devices.
So why the petition to change? I’ll start by stating that I have no connection to NextNav, nor insider knowledge about their motivation (or grudge to bear). But I can see a few clear reasons the petition would benefit them.
First: It would essentially grant them exclusive rights to a portion of the band. This is akin to the exclusive licenses that cellular companies are granted when they win spectrum auctions. Monopoly use of radio spectrum is extremely valuable.
Second: With exclusive use, NextNav would not have the pesky restrictions on ensuring their devices do not interfere with other devices sharing the same spectrum. This means they could operate at much higher power levels, to transmit stronger signals over longer distances. This greatly improves the ability to address applications — like asset tracking — that may not benefit from limited range and discontinuous networks. But more specifically, NextNav notes in their petition that by operating at full power, they could offer wireless services that are similar to cellular 5G. [You can read the full petition here].
This appears to be a blatant request for monopoly use of a valuable segment of radio spectrum, without paying a multi-billion licensing fee and for the primary application of 5G-like services. There is no good reason the government should be considering this petition seriously.
Innovation happens in the open. Think about how many different product categories came out of Bluetooth — which operates in the 2.4 GHz unlicensed spectrum. Headphones, wireless speakers, car infotainment systems, medical monitors, home automation, game controllers, computer peripherals, smart watches, wireless printers, pet trackers, activity monitors. These are all Bluetooth enabled product categories that each have dozens of competitors.
When you look at the innovation in the licensed cellular band you see far less innovation. There are many different kinds of phones, but they all come from an extremely limited number of product companies. There are a few tablets – also from those same manufacturers. Cellular modules have been built into cars and wireless gateways (most of which then connect to Bluetooth, wifi and other unlicensed edge-application devices).
The laws of physics define the total amount of radio spectrum. There’s no way to create more. So we need to use the spectrum available in the most beneficial way. There are only a few areas of the spectrum that have been specifically carved out for unlicensed use. The core ones are 915 MHz, 2.4GHz, 5 GHz and 60 GHz. These very few bands are where we have Bluetooth, wifi, RFID, LoRa, Zigbee, Z-Wave, NFC, Thread, DECT, Ant+ and a few others. These are protocols where there is massive innovation and significant market competition.
It is really hard to see why the FCC should pivot from the current allocation of the 915 MHz band. So what are the odds they’ll make a change?
NextNav is a small company. In 2023, it did $3.86M in revenue, and as recently as 2021, they had only $1M in annual revenue. But they have 232 institutional shareholders (according to SEC 13D, G and F filings) that have driven the market capitalization of the company to $909 million dollars. Think about that – investors consider a company that does ~$4M in revenue at nearly a billion dollar valuation. I would venture to guess that some of those investors are betting on the FCC grant of a free spectrum monopoly through this petition. Companies that own monopoly license of radio spectrum have a relatively easy path to billions of dollars of revenue in a trillion dollar market. So many applications require wireless connectivity that whoever controls the spectrum, controls the entire market.
It will be interesting to follow this story, as established players in the ISM band have an opportunity to submit letters to the FCC in response to NextNav’s petition. But unfortunately, these are the kinds of stories that the journalistic press simply doesn’t cover. The only way to follow is to actively research as the events unfold. Spectrum allocation is not sexy enough for the nightly news.
But something as fundamental as how our country manages the limited wireless spectrum at our disposal should be front page news. Wireless applications are so significant that they impact the entire economy. GPS alone has a trillion dollar global impact. IoT is growing to be an equally large market. Let’s hope the FCC does not place the ISM band with a single company. Instead, leave the spectrum open to innovation and competition.
The post Tom Snyder: Spectrum request could be difference between monopoly, innovation first appeared on WRAL TechWire.