ժҪ �����ƶ�ͨ�Ż����з��Ӿ�NLOS(Non-Line of Sight)����ʱ����չ����ָ���ֲ�������,�������߲���ʱ��TOA(Time of Arrival)��λ�������ȵ�һ�����ݴ�����.�÷������ȶ�TOA�������ݽ��з���,���������Բ������Զ�λ����û�й��ס����������Ӷ�λ���Ĳ���ֵ,���������С��3��,Ȼ�������С����LS(Least Squares)�����ƶ�̨������й���.�������ݱ���,�����ݴ����������ܹ���Ч���NLOS����������TOA��λ�����ľ���,�����Ӿ�LOS(Line of Sight)���������µĶ�λ����Ӱ�첻��,���нϺõĻ�����Ӧ����.
Based on the statistical property of the non-line of sight(NLOS) propagation in the mobile communication environment, a data process method was presented to improve the position location accuracy of the time-of-arrival(TOA). All of the measured TOA data were analysed, and the data which were apparently non-reasonable and had no use to the location estimation, and even worsen the position location accuracy were eliminated, and the 3 data which had the minimum error were kept. The least-squares(LS) method was applied to evaluate thelocation of mobile station. The simulation results show that this data process method not only can effectively improve the position location accuracy of the TOA method in NLOS environment, but also has little disadvantage to mobile location in line of sight(LOS) environment. It has a good adaptability for the communication environment.
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