Joint TOA/AOA estimation of IR-UWB signals in the presence of multiuser interference

We present a joint estimator of the time-of-arrival (TOA) and angle-of-arrival (AOA) for impulse radio ultra-wideband (IR-UWB) localization systems in which an antenna array is employed at the receiver and multiuser (MUI) interference exists. The proposed method includes 3 steps: (1) time-alignment and averaging to reduce the power level of the MUI and background noise; (2) preliminary TOA estimation based on energy detection followed by quadratic averaging; (3) joint TOA and AOA estimation using a recently proposed log likelihood function, but further extended to consider the effect of MUI. The validity of the proposed method is demonstrated by numerical simulations over a realistic space-time channel model.