Robust range estimation in the presence of the non-line-of-sight error

The evolution to location-dependent services and applications in wireless systems continues to require the development of more accurate and reliable mobile positioning technologies. The major challenge to accurate location estimation is in creating techniques that yield acceptable performance when the direct path from the transmitter to the receiver is intermittently blocked. This is the non-line-of-sight (NLOS) problem, and it is known to be a major source of error in mobile location since it systematically causes the mobile to appear farther away from the base station than it actually is, thereby increasing the positioning error. We present a simple yet robust method for distinguishing between LOS and NLOS range measurements in a mixed measurement set and we validate its performance using simulations in several multipath channel environments.

[1]  M. V. Clark,et al.  A new path-gain/delay-spread propagation model for digital cellular channels , 1997 .

[2]  Gordon L. Stüber,et al.  Radio location in urban CDMA microcells , 1995, Proceedings of 6th International Symposium on Personal, Indoor and Mobile Radio Communications.

[3]  T. Rantalainen,et al.  Mobile station emergency locating in GSM , 1996, 1996 IEEE International Conference on Personal Wireless Communications Proceedings and Exhibition. Future Access.

[4]  J. M. Holtzman,et al.  Locating Mobile Stations with Non-line-of-sight Measurements , 2002 .

[5]  Sven Fischer,et al.  Time of arrival estimation of narrowband TDMA signals for mobile positioning , 1998, PIMRC.

[6]  Li Xiong,et al.  A selective model to suppress NLOS signals in angle-of-arrival (AOA) location estimation , 1998, Ninth IEEE International Symposium on Personal, Indoor and Mobile Radio Communications (Cat. No.98TH8361).

[7]  J. Holtzman,et al.  The non-line of sight problem in mobile location estimation , 1996, Proceedings of ICUPC - 5th International Conference on Universal Personal Communications.

[8]  Pi-Chun Chen,et al.  A non-line-of-sight error mitigation algorithm in location estimation , 1999, WCNC. 1999 IEEE Wireless Communications and Networking Conference (Cat. No.99TH8466).

[9]  S. S. Wang,et al.  Mobile location method for non-line-of-sight situation , 2000, Vehicular Technology Conference Fall 2000. IEEE VTS Fall VTC2000. 52nd Vehicular Technology Conference (Cat. No.00CH37152).