Bi-iteration multiple invariance subspace tracking and adaptive ESPRIT

A class of adaptive bi-iteration SVD (Bi-SVD) algorithms for tracking structured subspaces of the form E_=[E EΨ₁ EΨ₂... EΨ_n-1] is introduced, where E is an N×r, N⩾r orthonormal core basis matrix, and Ψ₁, Ψ₂, ..., Ψ_n-1 is a set of r×r subrotors. Structured subspaces of this kind arise in all forms of multiple invariance (MI) techniques, such as MI-ESPRIT. An adaptive MI-ESPRIT algorithm using Bi-SVD MI subspace tracking is developed. Computer experiments validate the theoretical results