Modal decomposition signal subspace algorithms

The broadband emitter location problem is treated as a separable multidimensional spectrum estimation problem by modal decomposition of the estimated spectral density matrix at the poles of the sources. This modal decomposition method extends conventional sinusoidal (frequency bin or harmonic retrieval type) separation approaches to broadband sources. The modal decomposition is accomplished using overdetermined ARMA pole estimates and a Prony-like method with singular value decomposition for residue estimation. The signal subspace approach of Schmidt (1979), Su and Morf (1982) is extended and applied to the decomposed spectral residues for determination of source locations. Simulation results are given with comparison to MLM, MUSIC and EV methods applied at source peaks.