Kudos to FCC for beginning to tackle key noise-floor issue in technical inquiry
There’s a lot happening in the communications world right now. Consumers continue to drop landline subscriptions at an alarming rate, opting instead to depend solely on commercial wireless offerings. Both the United States and Mexico are conducting very different, but highly innovative spectrum-allocation exercises—the 600 MHz incentive auction in the U.S. and the Red Compartida procurement for a wholesale 700 MHz system. In the public-safety space broadband initiatives involving IP-based LTE and next-generation 911 technologies are gathering momentum.
Meanwhile, computing improvement continue to let devices become smaller, less expensive and have increased functionality. They also are highly reliant on software, which makes them more flexible—and more vulnerable to attacks from cybercriminals and others.
Projections indicate that there will be tens of billions more devices in use during the next few year as the Internet of Things (IoT) push gathers momentum. In addition, there are constant breakthroughs in the areas of drones and self-driving vehicles, all of which rely on wireless communications in some way to navigate and avoid collisions.
With so many ongoing initiatives, it’s hard to keep up with everything on a day-to-day basis. It’s even tougher to take the time to step back from the daily grind and assess “big picture” issues.
Last week, the FCC’s office of engineering and technology and the Technological Advisory Council took a step in this direction by initiating an inquiry that is designed to ask what impact all of this technological innovation in the wireless industry is having on the radio-frequency (RF) noise floor—the most fundamental barrier that wireless technologies must overcome.
I’m not an engineer, so I don’t know whether the FCC is asking the right technical questions. Nor am I a lawyer, so I don’t know exactly how much of this topic really falls within the FCC’s legal jurisdiction, if action needs to be taken.
However, I am glad that the FCC is examining the issue, because it is clear that such a review is needed, and it has to start somewhere. The RF environment has changed at a remarkable rate during the last decade, as we’ve had more wireless devices than people on the planet for the past few years.
And now, with the Internet of Things (IoT) trend gaining momentum, projections indicate that wireless devices could outnumber people by a factor of 10 within the next decade.
On numerous occasions, I’ve asked really smart people in the industry what all of these devices will do to the noise floor, and the responses have been all over the map. Some have said it could be an issue, while others say that it is not a problem, because most of the devices use wireless technologies that operate at very low power levels.
Of course, with many things in life, adding a bunch of small items together can result in a significant impact—in this case, a negative impact caused by a higher noise floor that would impact all things wireless.
But that has not occurred. Sure, there are stories of interference, but not nearly as many as I would have guessed, given the proliferation of wireless signals during the past several decades. I’m constantly amazed how engineers continually develop solutions to resolve contention-based interference; I figured the 2.4 GHz Wi-Fi band would have been rendered effectively useless years ago, but that’s far from the case.
This FCC inquiry is not designed to be a comprehensive study of the noise-floor issue, but it does represent a much-needed start. Ultimately, having a better understanding of noise-floor activities—likely with cooperative efforts from several other technical and regulatory entities—could help regulators better understand RF realities to forge better spectrum policies.
Perhaps we will learn that the noise floor is not really impacted by low-power devices, no matter how many of them are active in even very limited space. Or maybe the problems are limited only to certain kinds of receivers, so exclusive use of certain technologies can enable greater reuse/sharing of airwaves to promote greater spectral efficiency. Or maybe we’ll find that there is a saturation point for RF signaling that needs to be avoided, no matter how clever the engineers or technology.
I certainly don’t know what the answers will be, but there is no question that this is a discussion that is needed seem destined to move into an increasingly wireless world. By studying the noise-floor question correctly, hopefully we can learn how deep the water is before plunging headfirst into the wireless pool.