Analysis: 75 Case Studies of Active RFID in Action

Most of the case studies refer to ranges of up to five metres, closely followed by five to 30 metres but about 20 per cent are in the range 30 to 300 metres. Although a few companies have claimed to achieve up to a few kilometres range over the years, IDTechEx has yet to find any such systems in action. There are many reasons for the choices of range for active tags, including the fact that passive tags (with no power source of their own) cannot achieve the longer ranges. Short range avoids confusion between small things, medium range copes with vehicles and people, etc, passing through large constricted areas, and long range is needed to locate things at a distance using beams. Positioning using techniques such as triangulation is not yet common in RFID but geofencing (monitoring movement between areas by having interrogators at entry and exit points, as an example) is commonplace.