Ultra-wideband localization systems are widely known to perform with high accuracy using time-of-flight (TOF) algorithms, which are demanding in terms of tag-side power consumption. Systems optimized for power efficient tags are prone to be implemented using time-difference of arrival (TDOA) algorithms. However, due to dilution of precision and the additional required synchronization, TDOA systems suffer from limited accuracy outside the area covered by the anchors. This work presents a new technique, combining TDOA and TOF measurements in a power efficient way. Experimental results are compared with pure TOF and TDOA measurements. The results of the new combined technique show similar accuracy and a reduction of 75 % tag-side power consumption compared to the TOF method.
