tailieunhanh - Báo cáo hóa học: "Research Article Two-Step Time of Arrival Estimation for Pulse-Based Ultra-Wideband Systems"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: Research Article Two-Step Time of Arrival Estimation for Pulse-Based Ultra-Wideband Systems | Hindawi Publishing Corporation EURASIP Journal on Advances in Signal Processing Volume 2008 Article ID 529134 11 pages doi 2008 529134 Research Article Two-Step Time of Arrival Estimation for Pulse-Based Ultra-Wideband Systems Sinan Gezici 1 Zafer Sahinoglu 2 Andreas F. Molisch 2 Hisashi Kobayashi 3 and H. Vincent Poor3 1 Department of Electrical and Electronics Engineering Bilkent University Bilkent Ankara 06800 Turkey 2 Mitsubishi Electric Research Labs 201 Broadway Cambridge MA 02139 USA 3 Department of Electrical Engineering Princeton University Princeton NJ 08544 USA Correspondence should be addressed to Sinan Gezici gezici@ Received 12 November 2007 Revised 12 March 2008 Accepted 14 April 2008 Recommended by Davide Dardari In cooperative localization systems wireless nodes need to exchange accurate position-related information such as time-of-arrival TOA and angle-of-arrival AOA in order to obtain accurate location information. One alternative for providing accurate position-related information is to use ultra-wideband UWB signals. The high time resolution of UWB signals presents a potential for very accurate positioning based on TOA estimation. However it is challenging to realize very accurate positioning systems in practical scenarios due to both complexity cost constraints and adverse channel conditions such as multipath propagation. In this paper a two-step TOA estimation algorithm is proposed for UWB systems in order to provide accurate TOA estimation under practical constraints. In order to speed up the estimation process the first step estimates a coarse TOA of the received signal based on received signal energy. Then in the second step the arrival time of the first signal path is estimated by considering a hypothesis testing approach. The proposed scheme uses low-rate correlation outputs and is able to perform accurate TOA estimation in reasonable time intervals. The simulation results are presented to analyze the performance of the .