Great variety of solutions for indoor location

Indoor location, or indoor positioning, is a way to locate objects or people inside buildings or underground using radio waves, magnetic fields, acoustic signals, or other sensory information collected by mobile devices.

Many different systems on the market

The localized nature of indoor location has resulted in many different systems on the market – all with pros and cons in their setup. Here are the technological options for indoor location:

  • Wi-Fi positioning is using existing Wi-Fi infrastructure making it cost efficient. Wi-Fi positioning uses different techniques, like RSSI or fingerprinting, to geolocate a device. The accuracy ranges from five to 15 meters depending on the physical surroundings. Floor level can be determined with Wi-Fi positioning.
  • Beacons are using Bluetooth technology and provide a high accuracy in geolocation, up to one meter. Each beacon covers 10-30 meters and beacons must therefore cover the entire indoor area to provide accurate and complete geolocation coverage. Beacon technology is supported by most operating systems, can detect floor location and is installed with easy effort.
  • Ultra Wideband (UWB) is suitable when very high accuracy is needed using short range radio frequency. Accuracy is down to less than 30 cm. Latency time is low and height can be measured. This technique requires special components making it suitable for demanding industry environments.
Other, not so commonly used indoor location technologies, are radio frequency identification, (RFID), camera systems, magnetic fields or acoustic signals.

Challenges with indoor location

There is no standard for creating an indoor positioning system. Spaces that are packed with different materials and moving groups of people can make the radio signal unreliable for accurate indoor positioning. A group of physical and mathematical methods are applied to compensate for these problems. Integration of data from various navigation systems with different physical principles increase the accuracy and robustness of the overall solution.

Indoor location and floor level detection

It is in most cases important to know on which floor a device is. Lacking that piece of information makes indoor positioning rather useless when it comes to buildings with many floors. Wi-Fi- positioning and beacons can solve this. The accuracy is higher with beacons but the investments probably lower using Wi-Fi. Ultra wideband technology also makes it possible to specify floor level but the UWB range is short and UWB requires new hardware making Wi-Fi positioning and beacons a better option.