Noniterative subspace tracking

A rank-one spherical subspace update that is appropriate for subspace-based methods like MUSIC and minimum norm is introduced. This noniterative, highly parallel, numerically stabilized, subspace update is closely related to rank-one eigenstructure updating. However, a rank-one subspace update involves less computation than simple rank-one correlation accumulation. Moreover. The frequency tracking capabilities of the noniterative subspace update are virtually identical to and in some case more robust than the more computationally expensive eigen-based methods.>