The maximum likelihood estimate for radiation source localization: Initializing an iterative search

The maximum likelihood estimate approach is adopted in this paper for finding the unknown radiation source location and strength. The problem is nonlinear and has to rely on iterative numerical algorithms. Since the problem has possibly multiple local maxima, the initial estimate in those iterative algorithms plays a critical role in guaranteeing the global optimum. This paper proposes a way to generate such an initial estimate which is easy to calculate. Besides some insights that justifies the proposed approach, it is shown that the proposed initial estimate actually converges to the true but unknown maximum likelihood estimate asymptotically thus ensuring that the initial estimate is indeed in a neighborhood of the maximum likelihood estimate and consequently the convergence to the global optimum by local iterative numerical algorithms.

[1]  Kenneth R. Muske,et al.  Least squares estimation techniques for position tracking of radioactive sources , 2001, Autom..

[2]  Kung Yao,et al.  A maximum-likelihood parametric approach to source localizations , 2001, 2001 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings (Cat. No.01CH37221).

[3]  Michael Rabbat,et al.  Decentralized source localization and tracking , 2004 .

[4]  D. Stephens,et al.  Detection of moving radioactive sources using sensor networks , 2004, IEEE Transactions on Nuclear Science.

[5]  A.H. Sayed,et al.  Network-based wireless location: challenges faced in developing techniques for accurate wireless location information , 2005, IEEE Signal Processing Magazine.

[6]  Ali H. Sayed,et al.  Network-based wireless location , 2005 .

[7]  Alfred O. Hero,et al.  Energy-based sensor network source localization via projection onto convex sets , 2005, IEEE Transactions on Signal Processing.

[8]  B. Ristic,et al.  On Localisation of a Radiological Point Source , 2007, 2007 Information, Decision and Control.

[9]  R. Vilim,et al.  RadTrac: A System for Detecting, Localizing, and Tracking Radioactive Sources in Real Time , 2009 .

[10]  K. Mani Chandy,et al.  Sensor networks for the detection and tracking of radiation and other threats in cities , 2011, Proceedings of the 10th ACM/IEEE International Conference on Information Processing in Sensor Networks.

[11]  Dorit S. Hochbaum,et al.  Nuclear threat detection with mobile distributed sensor networks , 2011, Ann. Oper. Res..

[12]  E. Bai,et al.  Detection of shielded radionuclides from weak and poorly resolved spectra using group positive RIVAL , 2013 .

[13]  Raghuraman Mudumbai,et al.  On the Gradient Descent Localization of Radioactive Sources , 2013, IEEE Signal Processing Letters.

[14]  B. Deb Iterative Estimation of Location and Trajectory of Radioactive Sources With a Networked System of Detectors , 2013, IEEE Transactions on Nuclear Science.