The problem of localizing an IR-UWB transmitter from the signals received at several anchors is considered. The positioning problem is typically solved in a two-step approach where in the first step the Time of Arrival (TOA) is estimated independently at each anchor, and the position estimate is found in a second step. However, this approach can be improved, especially in challenging scenarios, if the positioning problem is treat as a whole, that is, the target position is estimated directly from the signals received on each anchor (Direct Position estimation DPE). In this paper, we present a different approach that sits halfway between these two approaches. The algorithm is based on a soft two-steps approach, where several possible TOA estimators are selected in the first step, and then the best estimators are used to find the position. The performance of the method is assessed under the framework of the IEEE 802.15.4a channel models.

Peer Reviewed