Rebuilding Smart Devices The technology already inside your phone knows exactly where you are, and what changes when everything else catches up Bluetooth location accuracy sits between three and five metres on a good day. Ultra-Wideband delivers precision to within ten centimetres consistently. That difference determines whether a smart lock opens as you walk toward it or waits while you dig through your bag. The wireless technology behind that precision has been inside iPhones since 2019, inside Samsung flagships since 2020, and inside the car keys of BMW, Hyundai, and Mercedes-Benz drivers since 2022. Most people carrying those devices have never heard its name. Bluetooth Lies About Where Your Devices Are Every wireless technology built for location, whether Bluetooth, Wi-Fi, or the positioning systems inside large buildings, estimates distance by measuring signal strength. The assumption behind that approach is simple: a strong signal means the device is close, and a weak signal means it is far away. That assumption collapses the moment a wall, a human body, or a metal shelf enters the picture. Bluetooth shares its frequency with Wi-Fi routers, microwave ovens, and baby monitors. All of them compete for the same slice of airspace inside your home, your office, and every building you walk into. Signal strength in that environment shifts constantly and without warning. Walls absorb the signal and furniture scatters it back at different angles. The phone receives several versions of the same signal arriving from different directions and has no reliable way to choose between them, so it averages the readings and calls it a location. That averaged guess is why your phone says your keys are nearby when they are behind a closed door two rooms away. Signal strength has always been a shortcut standing in for a measurement that wireless technology previously lacked the precision to take directly. Ultra-Wideband takes that measurement directly and the shortcut becomes unnecessary. UWB Calculates Distance While Bluetooth Guesses The assumption people carry about Ultra-Wideband is that it competes with Bluetooth the way 5G competes with 4G, a newer version of the same thing doing the same job faster. That assumption is why so many products still ship without it. Bluetooth handles audio streaming, file transfer, and device pairing, work it has always been designed to do well. Ultra-Wideband was built for a completely different job. Where Bluetooth estimates how close something is, Ultra-Wideband calculates the exact physical distance between two devices using the speed of light as its measuring tool. Both technologies run on the same device at the same time without interfering, because the problem each one solves belongs to a separate category. That separation matters the moment precision becomes the requirement. A Bluetooth system can tell you that a surgical instrument is somewhere in the ward. An Ultra-Wideband system tells you which shelf it is on, verified to within ten centimetres, as confirmed by hospitals already running UWB asset tracking across live ward floors . Pairing headphones does not need that level of accuracy. Locating equipment during a medical emergency requires every centimetre of that accuracy. Ultra-Wideband calculates exactly where things are at any given moment. Bluetooth makes its best guess and hopes the result is close enough. One Chip, Three Problems Solved On March 10, 2026, STMicroelectronics launched the ST64UWB family at Embedded World in Nuremberg, the first Ultra-Wideband chip family to support both the current wireless ranging standard and the next-generation specification arriving to replace it, as confirmed in the official STMicroelectronics press release . Three chips shipped simultaneously, each targeting a different real-world problem that existing wireless technology could not solve precisely enough. The first chip handles car digital keys and vehicle entry. The second manages smart locks and building access. The third adds on-chip processing for sensing inside vehicles, including detecting whether a child has been left in a back seat, recognising a foot kick to open a boot hands-free, and guiding a car into a parking space. According to STMicroelectronics, that third chip delivers twice the positioning accuracy of previous Ultra-Wideband hardware by using a wider signal channel than the standard requires. Daniel Siekmann, Head of Car Access Hardware at Forvia Hella, confirmed the new standard gives car keys more than eight times the operating range of the previous generation, reliable enough to work from inside a bag or a back pocket without requiring the key to be held in hand. The same week, Nuki Home Solutions , one of Europe’s leading smart lock manufacturers, confirmed it is building with the new chip to bring hands-free unlocking to homes across the region under the Aliro Alliance, an industry group that sets the shared standard for UWB-based access control across smart locks, hotels, and commercial buildings. UWB Uses Light to Measure Distance Ultra-Wideband works by sending short radio pulses between two devices and measuring exactly how long those pulses take to arrive. That measurement is called the Time of Flight, and it is what makes UWB precise. Because radio waves travel at the speed of light, the travel time converts directly into a precise physical distance, accurate to within ten centimetres in open conditions and under seven centimetres in cluttered environments, as verified testing published by the FiRa Consortium confirms . The security advantage of that method runs deeper than most people expect. Wireless car keys built on signal strength are vulnerable to a theft technique where a criminal uses two small devices to silently extend your key’s signal from inside your home to your car parked outside, tricking the car into thinking the key is right there. Ultra-Wideband closes that vulnerability at the level of the measurement itself. A criminal can intercept and forward a radio pulse, but the act of forwarding it adds travel time. That added time tells the UWB system the key is further away than it appears, and the door stays locked. The Car Connectivity Consortium has confirmed that Ultra-Wideband is the only wireless technology meeting the secure distance measurement their digital key standard requires. A relay device can forward a radio signal. Faking how long that signal took to travel is beyond what any device can do. Bats Cracked This Problem First The bat does not guess its way through a pitch-black cave. It fires ultrasonic pulses and measures the precise time those pulses take to bounce off a surface and return. That return time tells it exactly where the wall is, with enough precision to catch a moth mid-flight in complete darkness. The volume of the echo carries almost no useful information. The timing carries everything the bat needs to navigate. Ultra-Wideband applies that same logic to radio pulses traveling at the speed of light. The frequency is different and the medium is different, but the principle is the same one nature solved long before wireless technology existed. A pulse leaves the device, reaches the target, and returns. The time that journey takes converts directly into a precise physical distance. Signal strength plays no role because it was never the right measurement to begin with. That is why Ultra-Wideband performs reliably inside buildings where GPS signals can not penetrate and in cluttered environments where Bluetooth estimates fall apart. The pulses are short enough and the signal channel wide enough that the system separates the direct arrival from reflections bouncing off walls and furniture, a capability the FiRa Consortium has verified across real-world indoor environments with accuracy under ten centimetres. Guesswork Has an Expiry Date ABI Research forecasts that Ultra-Wideband device shipments will grow at 21% every year between 2025 and 2030, a pace that puts 1.4 billion UWB-enabled devices in circulation by the end of the decade. Over 436 million shipped in 2024 alone, with 60% of those chips sitting inside smartphones. That volume represents infrastructure already sitting inside the pockets of hundreds of millions of people, waiting for the products built around it to catch up. The consequences of that infrastructure are already measurable in places where precise location was previously impossible to achieve reliably. Manufacturers in industrial settings that replaced signal-strength positioning with Ultra-Wideband asset tracking accurate to under ten centimetres recorded a 30 to 40 percent drop in forklift collision insurance claims, according to Mordor Intelligence’s verified March 2026 market analysis . Fleet insurers serving vehicles fitted with UWB-based entry systems responded with premium reductions of up to 12%. Precision location changed the financial calculation alongside the product experience. Every door lock, car key, payment terminal, and hospital asset tracker still running on signal strength estimation belongs to a category the market is actively moving away from. The chips are already shipping at a meaningful scale. The automotive standard is fully certified and in production. The smart lock manufacturers have already committed their next generation to it. What determines the outcome for every product still built on estimation is how long its builders wait before making the same decision the early movers already made. About the Author I help AI startups communicate what their products really do — clearly, honestly, and in language their users actually understand. If your product is more powerful than the way it is currently being described, let us fix that together. Continue Reading → The Cost of AI Over-Reliance Is Paid in Human Thinking — What happens to critical thinking when AI fills every gap before you notice the gap exists. → Voice Is Becoming the Foundation of Every Product Interface: ElevenLabs Just Proved It — Why the window for building with voice is already open. Ultra-Wideband Knows You Are Approaching: The Wireless Standard was originally published in Artificial Intelligence in Plain English on Medium, where people are continuing the conversation by highlighting and responding to this story.