A joint TOA/AOA constrained minimization method for locating wireless devices in non-line-of-sight environment

Non-line-of-sight (NLOS) propagation degrades the performance of wireless location systems. Thus, developing algorithms that are robust to NLOS is of great importance. This paper introduces a new location technique that utilizes time of arrival (TOA) and angle of arrival (AOA) measurements. In the proposed method, we assume the signal from the mobile station reaches each base station via one dominant scatterer. By including the scatterer's coordinates as unknowns in a TOA/AOA-based cost function and imposing some equality and inequality constrains, the location of the mobile station (MS) is shown to significantly improve. The performance of the proposed algorithm is assessed and compared with that of existing algorithms through extensive simulations.