Open AccessTime of arrival estimation based on clustering for positioning in OFDM system
Author(s) -
Zhang Zhenyu,
Kang Shaoli
Publication year - 2020
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2019.0943
Subject(s) - computer science , time of arrival , estimator , orthogonal frequency division multiplexing , cluster analysis , multipath propagation , base station , cramér–rao bound , real time computing , algorithm , estimation theory , telecommunications , statistics , wireless , mathematics , artificial intelligence
In positioning research based on the orthogonal frequency division multiplex (OFDM) system, the observed time difference of arrival positioning method is a widely studied direction. The terminal measures the reference signal sent by the base station to calculate the time of arrival (TOA). Using TOA information, the location of the terminal can be identified. So the accuracy of the positioning is highly dependent on the results of the TOA measurements. Terminals often have difficulty measuring accurate TOA due to multipath channels and occlusion of obstacles. This study proposes two clustering‐based TOA estimation methods. The cluster‐based Max‐peak estimator is used to solve the problem that the energy of the first‐path is not the strongest in the case of multipath. Moreover, a cluster‐based adaptive threshold estimator is used to estimate TOA when the power of the direct path is low. The joint estimator of the two methods is designed to improve estimation accuracy. The proposed method is tested in the OFDM localisation environment, and the results demonstrate that the proposed method has better performance than the conventional way.