Estimation of Time Difference of Arrival (TDOA) for the Source Radiates BPSK Signal

Time difference of arrival (TDOA) technology has been widely used in positioning and navigation system recently. The position estimation of a source through determining time difference of arrival (TDOA) of its signal among distributed sensors has many applications in civil as well as in the military. According to civil aspect, in mobile communication is widely used TDOA to perform location of cell phones of their subscribers and mobile stations using fixed base stations and also in costal stations is used TDOA to estimate boats and ship's location using acoustic waves. According the military aspect, it used to locate enemy's emitting devices such as radars, communication devices in the battle field. In this research paper we analyse the performance of TDOA estimation for Binary phase shift keying (BPSK) signals, the whole scenario for estimating time-difference-of-arrival (TDOA) measurements was considered. The cross-correlation among arbitrary sensors is used to estimate TDOA also by exploiting the spectral characteristic of the received signals by considering the maximum likelihood generalized cross correlation (ML-GCC) the source will as unknown position emitting BPSK signal corrupted by the white Gaussian noise, The problem studied is time-difference of arrival estimation in a multipath channel. The TDOA measurement can used for solving the localization problem typically implies cross-correlating the noisy signals received at pairs of sensors deployed within reception range of the source. Correlation-based localization is severely degraded by the presence of multipath. In Simulation results show us that the proposed method for TDOA can achieve the Cramer-Rao lower bound (CRLB) accuracy compared with changing the signal-to-noise-ratio (SNR) the observation time and bandwidth (BW) of the signal and also show the good performance of accuracy of the proposed source localization methods. .