Benefits from cooperation in simultaneous anchor-less tracking and room mapping based on Impulse Radio - Ultra Wideband devices

In this article, a method is proposed to jointly estimate both the dimensions of a rectangular room and the relative locations of wireless devices communicating in this room. Relying on Low Data Rate (LDR) Impulse Radio - Ultra Wideband (IR-UWB) links, one can determine accurate estimates of the propagation delays corresponding to the direct path and the four single-bounce paths reflected on surrounding walls. Once properly ordered over each single link, these five delays enjoy explicit mathematical relationships with the transmitter/receiver nodes coordinates and the dimensions of the rectangular room. We propose herein new solutions to related underlying problems such as data association, initialization and tracking through Extended Kalman Filter (EKF) in a cooperative context including more than two mobile devices. The impact of the Time Of Arrival (TOA) estimation precision, the initial guess and the actual room dimensions is then evaluated through canonical simulation scenarios.