A selective model to suppress NLOS signals in angle-of-arrival (AOA) location estimation

Angle-of-arrival (AOA) is a key technique in wireless location estimation. The study of AOA becomes very important with the FCC ruling regarding the wireless Enhanced 911 (E911) emergency calling systems. This paper studies the performance of AOA in a cellular environment. Special attention is drawn to the non-line-of-sight (NLOS) problem that is a significant error source in position estimation. A model is proposed to identify and to reduce the NLOS errors with the coordination of many base stations. The simulation results show that the proposed algorithm is quite efficient in reducing the estimation error when NLOS is present.