Introduction to AirTags : 1
THE BEGINNING: GPS
GPS relies on a network of satellites that transmit signals to Earth, allowing receivers to calculate their precise location by measuring signal delays from at least four satellites. This builds on the Doppler Effect, first observed during the Sputnik era, where shifts in radio signals helped track movement.
Today, GPS applies these principles globally for accurate navigation and tracking. However, it struggles in indoor, urban, and underground areas where signals are obstructed.
In such cases, short-range technologies like Bluetooth and Ultra-Wideband (UWB) offer more precise tracking in confined spaces, overcoming GPS limitations and enhancing location accuracy in challenging environments.
THE NEXT STEP:BLUETOOTH
Named after a 10th-century Danish king, Bluetooth uses weak radio waves to transmit data directly between devices. Its low power consumption makes it ideal for battery-powered gadgets, allowing most Bluetooth finders to last over a year on a coin battery. However, its range is limited to about 9 meters.
Unlike GPS, which relies on satellites, Bluetooth connections work independently without a router or intermediary device. It operates within a small frequency band around 2.4 GHz, using 79 radio channels. When two devices pair, they randomly select a frequency, then continuously hop between these channels multiple times per second to maintain stability.
THE FINAL STEP: UWB
Like Bluetooth, ultra-wideband (UWB) is a short-range, wireless communication protocol that operates through radio waves.
Unlike Bluetooth, which uses a 1 Mhz bandwidth, devices enabled with UWB utilise a larger channel bandwidth (500MHz!) and hence are able to capture highly accurate spatial and directional data. The UWB positioning process instantaneously tracks the device’s movements in real-time. In doing so, UWB-enabled devices can understand both motion and relative position.
UWB offers higher accuracy in both line-of-sight and non-line-of-sight scenarios, even in cluttered environments. Using angle-of-arrival (AoA) technology, it pinpoints device locations with centimeter-level precision. It can also detect whether an object is stationary, approaching, or moving away.
This concludes this part of the blog-series, we hope to see you come back to read some more mind bending insights on this topic very soon!



