Title :
Quantifying the advantages of joint processing in TDOA estimation
Author_Institution :
Sch. of Electr. Eng., Tel-Aviv Univ., Tel-Aviv, Israel
Abstract :
We address the problem of passive estimation of the Time-Difference of Arrival (TDOA) of an unknown, stochastic signal, at two sensors. The key question addressed here is whether additional sensors, receiving the same signal at various relative delays, can serve to improve the accuracy in estimating the TDOA of interest between the first two sensors (without exploiting any underlying parameterization, such as dependence on the transmitter´s location). We derive the Cramér-Rao Lower Bound (CRLB) on the resulting joint estimation error in a model which possibly includes multipath reflections. We show analytically, that in a multipath-free scenario, at high to moderate Signal to Noise Ratios, additional sensors do not offer any improvement in accuracy. However, we also demonstrate (numerically) that in the presence of multipath reflections (possibly received at all sensors), the additional sensors can indeed assist in estimating the TDOA of interest with improved accuracy.
Keywords :
array signal processing; direction-of-arrival estimation; time-of-arrival estimation; CRLB; Cramér-Rao lower bound; TDOA estimation; array signal processing; joint estimation error processing; multipath reflections; passive estimation problem; relative delays; sensors; signal to noise ratios; time-difference of arrival estimation; Accuracy; Delay; Estimation error; Signal to noise ratio; Vectors;
Conference_Titel :
Sensor Array and Multichannel Signal Processing Workshop (SAM), 2012 IEEE 7th
Conference_Location :
Hoboken, NJ
Print_ISBN :
978-1-4673-1070-3
DOI :
10.1109/SAM.2012.6250468