Ultra-wideband (UWB) is a broadband signal which can be used for indoor positioning. UWB is mostly used in industry environments where the positioning accuracy must be 10-30 cm. The position is determined by a transit time method (Time of Flight, ToF). The radiated light between the object and at least 3 Anchors (receivers) is sufficient to calculate the exact position. A tag is attached to the asset and transmits the required data to the permanently installed Anchors. Indoor positioning with Ultra-wideband can be realized as a server-based or client-based installation.
Sources http://whatis.techtarget.com/definition/ultra-wideband http://www.elektronik-kompendium.de/sites/kom/1010131.htm http://www.itwissen.info/definition/lexikon/Ultra-Breitband-UWB-ultra-wideband.html