Military radar might be messing with your Wi-Fi router

Published Nov 1, 2026, 5:30 PM EST Monica J. White is a journalist with over a decade of experience in covering technology. She built her first PC nearly 20 years ago, and she has since built and tested dozens of PCs. PC hardware is her main beat, and graphics cards and the GPU market at large are her main area of interest, but she has written thousands of articles covering everything related to PCs, laptops, handhelds, and peripherals. From GPUs and CPUs to headsets and software, Monica's always willing to geek out over all things related to computing. Outside of her work with How-To Geek, Monica contributes to TechRadar, PC Gamer, Tom's Guide, Laptop Mag, SlashGear, Whop, and Digital Trends, among others. Her ultimate goal is to make PC gaming and computing approachable and fun to any audience. Monica spends a lot of time elbow-deep in her PC case, as she's always making upgrades, testing something, or plotting out her next build. She's the go-to tech support person in her immediate circle, so she's never out of things to do. Whenever she has spare time, you'll find her gaming until the early hours and hanging out with her dog. When your Wi-Fi drops unexpectedly, what's your first guess? Mine is, naturally, to blame the ISP. Then, if I'm on my phone or something else portable, I'll start wondering about Wi-Fi dead zones. Know the one thing I probably don't think about? The military. But it turns out that consumer routers can be affected by protected radar systems in unexpected ways. Radar gets priority, and your router has to respect that You might think that your router is your own, and so is your connection. Well, that's mostly true, but not entirely. Some of the frequencies your router uses also share space with radar systems, and that's entirely unrelated to whatever is happening in your house. These radar systems include military, aviation, and even weather radar, and all those things you probably hardly ever thing of and have no influence over might be able to influence your router. Still, I don't mean to imply they just randomly mess with your connection for the fun of it. In fact, to make sure everyone's getting along, routers use something called Dynamic Frequency Selection (DFS). This lets them operate on additional 5GHz channels, such as 52-64 and 100-140, provided they follow certain rules. And it's a pretty good deal for us, actually, because DFS channels tend to be less crowded than the regular ones, which is good news for Wi-Fi performance. Except ... Radar gets priority. That's the trade-off. A radar detection can make your Wi-Fi suddenly disappear Your router may have to abandon its channel within seconds So, let's say your router is just doing its thing and minding its own business, and then it detects radar activity on the DFS channel it's using. What then? Well, it has to pack its bags and leave, and quickly, too. Under US regulations, your router in that scenario has just 10 seconds to stop transmitting on that channel, and it can't use it again for at least 30 minutes. Rude (but necessary). This doesn't mean you're going to be left with zero Wi-Fi, fortunately. Your router can, and should, switch lanes to another available channel, but devices connected to the 5GHz band might temporarily lose their connection in the process. If you're just watching some casual Netflix, that's probably fine. But if you're on an important call or in the middle of a game, even a split second of no internet can cost you precious time. Things get even more annoying if your router switches to another DFS channel. Before it can start broadcasting there, it may need to spend anywhere from one to ten minutes checking for radar activity (depending on the channel and local regulations). During that time, your 5GHz network might be unavailable. At least the 2.4GHz network should work, but that's where your smart home stuff probably lives, and not the main things like your computer. The best and worst part is that this can all happen without you ever knowing that radar was the reason, which can lead to some real head scratchers. Your router might already be telling you what's happening Check the channel and system logs before blaming your ISP The good news is that you might be able to figure out whether DFS is to blame before you set off on a crusade, intent on hunting down the cause of your internet suddenly dropping. Start by logging into your router's admin panel and checking your 5GHz wireless settings. If you're using a DFS channel, such as 52, 100, or 116, there's a chance radar detection could indeed be the culprit. Next, look through your router's system logs for messages mentioning "DFS," "radar detected," or unexpected channel changes. Some routers make this easier than others. Remember that not every channel switch or DFS event means that military radar was involved. That's just one of a few options, and false positives do happen. Besides, not every router even lets you take a peek. You can avoid DFS channels, but there's a trade-off A manual channel change might solve those mysterious disconnections If you're 100% sure that DFS is the cause of your various Wi-Fi woes, I get why you'd want to turn it right off. Usually, you can, but there's a catch (isn't there always). First, how to do it: Head back into your router's 5GHz wireless settings and look for an option to disable automatic DFS channel selection. You can also manually pick a non-DFS channel, such as 36, 40, 44, or 48. These are generally safe bets in terms of avoiding radar-related interruptions. You might also want to switch from 160MHz to 80MHz channel width while you're there. Those extra-wide 160MHz channels can overlap DFS frequencies even if your primary channel isn't actually one of them. The downside to it all is that non-DFS channels tend to be more crowded. Go figure, you're not the only one who doesn't want to get randomly disconnected. Military radar isn't necessarily your Wi-Fi's enemy I know all of this sounds supremely annoying, but DFS is actually a pretty clever solution to a problem that would otherwise leave us with fewer usable 5GHz channels. Instead of setting those frequencies aside entirely for radar purposes, regulators let our routers use them, too, as long as they go away when needed. I'd call that a win, but for that less congested connection, you might be paying with some stability (or predictability, at least).