Accession Number : ADA133810

Title :   Optimal Delay Estimation in a Multiple Sensor Array Having Spatially Correlated Noise.

Descriptive Note : Annual technical rept. 1 Nov 82-31 Oct 83,


Personal Author(s) : Kirlin,R Lynn ; Dewey,Lois A

PDF Url : ADA133810

Report Date : 30 Sep 1983

Pagination or Media Count : 68

Abstract : The maximal likelihood estimation of time-of-arrival differences for signals from a single source or target arriving at M or = 2 sensors has been the subject of a large number of papers in recent years. These time differences or delays enable target location. Nearly all previous work has assumed noises which are independent among all sensors. Herein noises are taken to have a complex correlation between sensors. A set of nonlinear equations in the unknown delays is derived and possible simplifications discussed. The unknowns are in one case the M-1 delays referred to the first sensor and in another case an M-1 dimensional subset of independent delays from the M(M-1)/2 pairwise delays. The Fisher information matrix (FIM) for the estimates is also derived. The Cramer Rao Matrix Bound (CRMB), which is the inverse of FIM, will show optimal estimator covariances; these are different than the covariances of correlator delay estimators derived by Hahn. Computer evaluations are given for CRMB elements with varied SNR and noise covariance values typical of turbulent boundary layer noise in towed arrays. (Author)

Descriptors :   *Maximum likelihood estimation, *Linear arrays, *Multisensors, Noise, Correlation, Target position indicators, Covariance, Signal to noise ratio, Nonlinear algebraic equations, Towed arrays, Delay, Optimization, Turbulent boundary layer, Charts

Subject Categories : Electrical and Electronic Equipment
      Statistics and Probability

Distribution Statement : APPROVED FOR PUBLIC RELEASE