Title :
Approximate maximum likelihood time differences estimation in the presence of frequency and phase consistence errors
Author :
Sen Zhong ; Wei Xia ; Zishu He
Author_Institution :
Sch. of Electron. Eng., Univ. of Electron. Sci. & Technol. of China, Chengdu, China
Abstract :
In passive location systems using time differences of arrival (TDOA) measurements, in order to digital processing, the received radio frequency (RF) signals are usually down-converted to baseband. In down-conversions, oscillators are used to mix the signals-of-interest to baseband. Frequency and phase consistence error between two oscillators degrade the performance of TDOA estimation between two sensors. Considering the oscillator consistence errors, the modified baseband data model of time delay estimation is presented. Next, the approximate maximum likelihood (AML) TDOA estimator based modified model is proposed to reduce the TDOA estimation error. Furthermore, two simplified versions of AML estimator are also developed, which include the two-dimensional (2D) search and one-dimensional (1D) search AML methods. Simulation results confirm the performance of these estimators.
Keywords :
delay estimation; maximum likelihood estimation; radiofrequency oscillators; time-of-arrival estimation; 2D search; AML estimator; ID search; RF signals; TDOA estimation error; approximate maximum likelihood; baseband data model; down-conversions; frequency consistence errors; maximum likelihood time difference estimation; one-dimensional search; oscillators; phase consistence errors; radio frequency signals; sensors; time delay estimation; time differences of arrival measurements; two-dimensional search; Estimation; Sensors; Simulation; approximate maximum likelihood (AML); baseband; local oscillator (LO); time differences of arrival (TDOA);
Conference_Titel :
Signal Processing and Information Technology(ISSPIT), 2013 IEEE International Symposium on
Conference_Location :
Athens
DOI :
10.1109/ISSPIT.2013.6781898
