Title :
Analysis on TOA and TDOA Location Estimation Performances in a Cellular System
Author :
Hara, Shinsuke ; Anzai, Daisuke ; Yabu, Tomofumi ; Derham, Thomas ; Zemek, Radim
Author_Institution :
Grad. Sch. of Eng., Osaka City Univ., Osaka, Japan
Abstract :
In a computer simulation result on the location estimation for a cellular system, we found that a Time Difference Of Arrival (TDOA) method outperforms a Time Of Arrival (TOA) method when Non-Line-Of-Sight (NLOS) channels are dominant, whereas the TOA method outperforms the TDOA method when LOS channels are dominant. We could not easily accept the result, because TDOA method loses one degree of freedom in the number of usable range estimates when selecting a range estimate as a reference and doubles the variance of range error when subtracting the reference range estimate. In this paper, we try to theoretically prove the interesting result by the computer simulation. We divide the root mean square location estimation error into two factors, such as the error variance contributed from range sampling error and the error bias contributed from positive NLOS range error. For the error variance, we evaluate it by the Cramer-Rao lower bound, whereas for the error bias, we analyze it by perturbation method.
Keywords :
cellular radio; mean square error methods; time-of-arrival estimation; Cramer-Rao lower bound; NLOS channel; TDOA location estimation performance; TOA; cellular system; computer simulation; nonline-of-sight channel; root mean square location estimation error; time difference of arrival; Channel estimation; Computer simulation; Estimation error; IEEE Communications Society; Mobile communication; Transmitting antennas;
Conference_Titel :
Communications (ICC), 2011 IEEE International Conference on
Conference_Location :
Kyoto
Print_ISBN :
978-1-61284-232-5
Electronic_ISBN :
1550-3607
DOI :
10.1109/icc.2011.5963134