Ultra-wideband (UWB) is a short-range radio technology that sends very short pulses across a wide band of frequencies, letting two devices measure the distance between them precisely by timing the signal.
In forklift safety, UWB is the radio many tag-based systems use to measure how far a pedestrian tag is from a truck-mounted unit, or to locate tags against fixed anchors in a real-time location system. Because it measures distance by signal travel time rather than signal strength, it ranges more consistently than Bluetooth or RFID in aisles full of metal racking. US rules define a UWB transmitter as one with a bandwidth of at least 500 MHz or a fractional bandwidth of at least 0.20.
UWB is a ranging and positioning radio, not a detection system on its own. It only sees people who wear a working, charged tag, so visitors and contractors without tags are invisible to it. Radio can also be blocked or reflected by dense loads and steel, which is why buyers should test zone accuracy at their own racking, doors and blind corners during a pilot. The proximity detection technologies comparison sets UWB against cameras, radar and LiDAR.