Ignore the scaremongers. 5G won’t interfere with weather satellites. Here’s why

5g weather satellite interference goes

5G will completely change the way we use our mobile phones, offering super high speeds that won’t just mean downloading your favorite shows faster. But 5G comes with a host of concerns, from limited range and poor building penetration to worries of adverse health effects.

But now there’s a new issue: weather satellites. An April article in Nature set the meteorological community into an uproar, as it detailed the potential fallout of a recent auction from the Federal Communications Commission of  24.25 to 24.45 and 24.75 to 25.25 gigahertz (GHz) spectrum. There’s one problem: that’s close to the frequency meteorologists use to detect water vapor in the air.

Disrupting the weather?

Water vapor emits a weak radio signal at a frequency of 23.8 GHz, which satellites detect. Water vapor imagery has become a crucial part of forecasting the weather, as it helps meteorologists better understand movement in the atmosphere, and provides computer models with crucial data to better forecast the development of storms.

“The fears are realistic, as a reduction in the ability to detect water vapor is estimated to return our forecast accuracy to levels last seen around 1980,” Kevin McMahon, executive director of mobile and emerging technologies at Chicago-based digital consultancy SPR, told Digital Trends. “We’re bumping up against nature. There are consequential trade offs to consider.”

5g weather satellite interference water vapor image
Water vapor imagery of the United States from Friday May 24, 2019. (NOAA)

The apparent assault on remote sensing of weather isn’t over, either. Future planned auctions may affect the detection of precipitation (36 to 37 GHz), temperature (50.2 to 50.4 GHz), and even the traditional cloud sensing of weather satellites (80 to 90 GHz).

But is all of this fear and loathing just a high-tech version of Chicken Little? Probably, and here’s why.

It’s all about propagation

To understand why, we first need to know the science behind how radio frequency works, most importantly in how it propagates. Perhaps the best way to understand this is to use the radios in our homes and cars as an example.

At very low frequencies, radio waves travel farther because they have longer wavelengths. They also can travel through objects easily. Think of a shortwave radio: broadcasts can travel around the world at night using relatively little power (it’s also in a propagatory ‘sweet spot’ too). Similarly, AM radio broadcasts, which have frequencies just below that of shortwave, can also travel long distances at night, but not as far as shortwave.

Now compare this to an FM signal, which uses much higher frequency. With a much shorter wavelength, FM radio signals rarely travel more than 100 miles or so at best. To transmit over a substantial distance, your power needs are much higher than the shortwave or AM bands.

Verizon 5G Node
Verizon 5G node. Julian Chokkattu/Digital Trends

Traditional mobile phones operate on frequencies well above FM radio. As you’d guess, the wavelengths are much shorter so the range is reduced even further, and its ability to deal with obstructions is far less robust. This is why early next-generation wireless networks in the U.S. were so poor: operating at frequencies of 1700 and 2100MHz, the range of towers was significantly less, and indoor reception was spotty.

It has gotten immensely better, but only thanks to an expansive (and rather closely spaced) network of cellular towers. But that’s not possible everywhere, and wireless companies — T-Mobile most notably — have hoarded lower frequency spectrum as it becomes available. But even there, it’s not clear quite yet how to get the super high speeds that 5G is expected to provide — since bandwidth is still tight.

So why use gigahertz spectrum in 5G, then?

A simple reason: congestion. Frequency spectrum on the lower bands are shared by dozens if not hundreds of uses. As a result, small portions of spectrum serve a whole lot of devices. As you get into the multi-GHz portion of the radio spectrum, there are far less people using it. So little, that the small hoses of bandwidth of lower band wireless become large pipes at these super high frequencies, or millimeter wave (mmWave).

mmWave covers frequencies roughly 30 to 300GHz, although frequencies as low as 24GHz are considered mmWave too. The amount of bandwidth available in mmWave is immense: experts believe mmWave has the potential to boost download speeds up to as much as 10Gbps — making all kinds of applications possible including live virtual and augmented reality, smart autonomous vehicles, and more. Any of these applications require massive amounts of bandwidth, and the spectrum just isn’t there across the lower bands to do it.

galaxy s10 5g speed test
Julian Chokkattu/Digital Trends

But let’s return to the discussion on propagation. Already at frequencies of 1700 and 2100MHz where most current networks operate, there are reception issues indoors and heavily obstructed areas. This is compounded as you go even higher in frequency.

“[5G] relies upon the millimeter-wave spectrum to deliver its top speeds, and it is a hard fact of physics that these higher frequencies degrade more easily, and cannot propagate as well as lower ones,” BroadbandNow policy expert Tyler Cooper explained to Digital Trends. “This means that 5G’s greatest potential will most likely be relegated to extremely dense urban ‘pockets.'”

Verizon’s finding this out as it rolls out its 5G network across the U.S. To cover cities, the company is forced to place a mini-tower on literally every corner of every block, as we found out in April testing the Verizon 5G network and again in May using the Galaxy S10 5G. Walk a block away from a transmitter and you’re back on the LTE network.

Satellites are safe

The realities of mmWave, and good old fashioned physics, are the reasons why weather satellites and any other potential user of multi-GHz frequencies are likely safe for the foreseeable future. No new technology is going to change this. While auctions may have opened up for the frequencies close to where these satellites operate, the frequencies sold are of questionable value to wireless carriers given their poor propagation performance.

Furthermore, it is not entirely clear that a wireless carrier would either need or want to use the small portion of the bands recently sold that might interfere with satellite imagery. Spectrum licensees are expected to keep interference to a minimum as a condition of their license. For the most part, carriers have been good stewards of their networks, and there’s really no reason to expect they wouldn’t be now.

Could there be problems down the road? Sure. But we may be years if not decades off from that — and by then we may have moved on to yet another next-generation technology. But for now, your meteorologist has nothing to fear.

Emerging Tech

How to watch SpaceX’s most difficult Falcon Heavy launch ever

SpaceX will launch a Falcon Heavy rocket Monday evening in its most challenging launch yet. The launch is scheduled for Monday June 24 at 8:30 p.m. PT, but is dependent on weather conditions. You can watch NASA's livestream with coverage…
Home Theater

Looking for the best 4K Ultra HD TVs you can buy? Here are five great options

If it's time to upgrade your old 1080p to a new 4K model but you don't know what to look for, fear not, as we're here with a list of the best 4K Ultra HD TVs to help make your buying process as easy as possible.

The best budget-friendly GoPro alternatives that won’t leave you broke

Cold weather is here, and a good action camera is the perfect way to record all your adventures. You don't need to shell out the big bucks for a GoPro: Check out these great GoPro alternatives, including some 4K cameras, that won’t leave…

The LG V50 ThinQ will be available from Verizon starting on June 20

LG has a habit of releasing too many phones. Following on the heels of the V40 ThinQ, the company has now unveiled the LG V50 ThinQ. There's 5G support, as well as an accessory that turns it into a foldable phone.

iOS 13 is here. Here's how to get it on your iPhone or iPod Touch

The iOS 13 public beta has been released, giving you a chance to try out iOS 13's new features. But how do you download Apple's latest software? Here's our guide on how to download the iOS 13 public beta.

The iOS 13 public beta is here and you can download it now

Apple announced iOS 13 during the keynote presentation at its 2019 Worldwide Developer Conference. This is the next version of its mobile operating system, which will come to an iPhone, iPad, or iPod near you soon.

Apple's new iPadOS public beta is now available for download

Apple announced the new iPadOS, a new operating system designed specifically for the iPad. It brings a number of new productivity features to the iPad, including the ability to use multiple windows of a single app at a time.

Master your newly updated iPhone with the best iOS 13 tips and tricks

The iOS 13 public beta is here. But there's a lot of new and confusing features to dive into in iOS 13. Don't flounder around looking for them -- here's a list of useful iOS 13 tips and tricks to get you started.

iOS 13 dazzles, but Apple turns down the lights with its new Dark Mode

Apple's iOS 13 is introducing a lot of new features to iPhones, but one of the biggest and most coveted additions absolutely has to be Dark Mode. Here's how to turn on Dark Mode in iOS 13, set an automatic timer, and more.

Researchers sent a fake, unblockable presidential alert to a 50,000-seat stadium

A group of researchers was able to send out fake, unblockable presidential alerts to phones in a 50,000-seat football stadium. The team from the University of Colorado Boulder figured out a way to spoof the alert and send it out.

Apple iPad with Wi-Fi and cellular gets $80 price cut on Amazon ahead of Prime Day

Apple iPads are getting a piece of the Amazon Prime Day action in the weeks leading up to July 15. Now on Amazon ahead of Prime Day, score your 32GB Apple iPad (Wi-Fi + cellular) for just $379, down from $459.

Amazon’s back-to-college store drops deals on refurbished items before Prime Day

Buying refurbished is a great way to save money, and Amazon has a ton of deals right now. While there's hundreds of Amazon refurbished items on the site, we've found 20 items that we think both college students and parents might be…

iOS 13 is the feature-filled update Apple’s iPhone needed

iOS 13 is here -- at least, the public beta has landed. You can install it now on supported iPhones. Check out our iOS 13 hands-on as we dive into some of the biggest new features, from Dark mode to the new Photos app.

Looking for a stylus for cheap? The Adonit Pro 4 is a great starting point

For casual note takers and sketch artists, the Adonit Pro 4 stylus is a low-maintenance, low-cost device for people just getting started with using a conductive pen on their smartphone or tablet.